BrainBlog

BrainBlog

Monday, December 20, 2004

Amnesia At The Movies: Eternal Sunshine, Memento, and Finding Nemo

Wherein the author finds that the fish gets it right and is pleased with the homage to Patient H.M.:

Sallie Baxendale. Memories aren't made of this: Amnesia at the movies. British Medical Journal 2004; 329: 1480-1483 (18 December). [doi:10.1136/bmj.329.7480.1480]

Full text:

Article [HTML]
Article [.pdf]

Now, where is that ad for the Lacuna Clinic? (grin) After all, Eternal Sunshine is BrainBlog's movie of the year!

Saturday, December 18, 2004

Lunesta (Eszopiclone)

With New Sleeping Pill, New Acceptability?
By ANDREW POLLACK
The New York Times
17 December 2004

Is it a wake-up call for the sleeping pill market? With Wednesday's approval of Sepracor's new drug, Lunesta, a taboo in the use of sleeping pills has been broken. Lunesta is the first sleeping pill whose label will not recommend it be taken for only 7 to 10 days.

[ ... Read the full article ... ] (free registration required)

Friday, December 17, 2004

Mixed Dementia

This week's Journal of the American Medical Association includes a clinical review about current knowledge of dementia in the presence of both probable Alzheimer disease and cerebrovascular disease, including neuropsychological and behavioral information, as well as a discussion of potential medications.
Mixed Dementia: Emerging Concepts and Therapeutic Implications
Kenneth M. Langa, MD, PhD; Norman L. Foster, MD; Eric B. Larson, MD, MPH
JAMA. 2004; 292: 2901-2908.

Context  The prevalence of mixed dementia, defined as the coexistence of Alzheimer disease (AD) and vascular dementia (VaD), is likely to increase as the population ages.

Objectives  To provide an overview of the diagnosis, pathophysiology, and interaction of AD and VaD in mixed dementia, and to provide a systematic literature review of the current evidence for the pharmacologic therapy of mixed dementia.

Data Sources, Study Selection, and Data Extraction  The Cochrane Database of Systematic Reviews was searched using the keyword dementia. MEDLINE was searched for English-language articles published within the last 10 years using the keywords mixed dementia, the combination of keywords Alzheimer disease, cerebrovascular disorders, and drug therapy, and the combination of keywords vascular dementia and drug therapy.

Evidence Synthesis  Dementia is more likely to be present when vascular and AD lesions coexist, a situation that is especially common with increasing age. The measured benefits in clinical trials for the treatment of mixed dementia are best described as statistically significant differences in cognitive test scores and clinician and caregiver impressions of change. In these studies, the control groups’ scores typically decline while the treatment groups improve slightly or decline to a lesser degree over the study period. Nevertheless, even the patients who experience treatment benefits eventually decline. Cholinesterase inhibitor (ChI) therapy for mixed dementia shows modest clinical benefits that are similar to those found for ChI treatment of AD. The N-methyl-D-aspartate (NMDA) antagonist memantine also shows modest clinical benefits for the treatment of moderate to severe AD and mild to moderate VaD, but it has not been studied specifically in mixed dementia. The treatment of cardiovascular risk factors, especially hypertension, may be a more effective way to protect brain function as primary, secondary, and tertiary prevention for mixed dementia.

Conclusions  Currently available medications provide only modest clinical benefits once a patient has developed mixed dementia. Cardiovascular risk factor control, especially for hypertension and hyperlipidemia, as well as other interventions to prevent recurrent stroke, likely represent important strategies for preventing or slowing the progression of mixed dementia. Additional research is needed to define better what individuals and families hope to achieve from dementia treatment and to determine the most appropriate use of medication to achieve these goals.

Wednesday, December 15, 2004

Hoarding Behavior in Brain Damage

From a University of Iowa press release:
Brain Region Identified That Controls Collecting Behavior

[snip]

By studying patients who developed abnormal hoarding behavior following brain injury, neurology researchers in the University of Iowa Roy J. and Lucille A Carver College of Medicine have identified an area in the prefrontal cortex that appears to control collecting behavior. The findings suggest that damage to the right mesial prefrontal cortex causes abnormal hoarding behavior by releasing the primitive hoarding urge from its normal restraints. The study was published online in the Nov. 17 Advance Access issue of the journal Brain.

[snip]

The UI team studied 86 people with focal brain lesions - very specific areas of brain damage – to see if damage to particular brain regions could account for abnormal collecting behavior. Other than the lesions, the patients' brains functioned normally and these patients performed normally on tests of intelligence, reasoning and memory.

[snip]

To determine if certain areas of damage were common to patients who had abnormal collecting behavior, the UI researchers used high-resolution, three-dimensional magnetic resonance imaging to map the lesions in each patient's brain and overlapped all the lesions onto a common reference brain.

"A pretty clear finding jumped out at us: damage to a part of the frontal lobes of the cortex, particularly on the right side, was shared by the individuals with abnormal behavior," Anderson said. "Our study shows that when this particular part of the prefrontal cortex is injured, the very primitive collecting urge loses its guidance.

"This finding sheds some light on a ubiquitous, nearly universal human behavior that we really don't know much about, and we can use this as springboard to think about normal collecting behavior."
[ ... Read the full release ... ]

Friday, December 10, 2004

In The Weeklies

This week's issue of the New England Journal of Medicine (09 December 2004) includes two research papers and one editorial comment on topics concerning Parkinson disease:

Levodopa and the Progression of Parkinson's Disease by The Parkinson Study Group. Abstract

Rivastigmine for Dementia Associated with Parkinson's Disease by M. Emre and colleagues. Abstract

Parkinson's Disease Dementia — A First Step?, an editorial comment by D. Z. Press. Extract

Wednesday, December 08, 2004

Abstract of the Day: Ritalin in Childhood Cancer Survivors

Mulhern RK, Khan RB, Kaplan S, Helton S, Christensen R, Bonner M, Brown R, Xiong X, Wu S, Gururangan S, Reddick WE. Short-term efficacy of methylphenidate: A randomized, double-blind, placebo-controlled trial among survivors of childhood cancer. Journal of Clinical Oncology. 2004 Dec 1; 22(23): 4743-51.

Division of Behavioral Medicine, Department of Hematology/Oncology, St Jude Children's Research Hospital, Memphis, TN 38105-2794, USA.

PURPOSE: Children surviving acute lymphoblastic leukemia (ALL) and malignant brain tumors (BTs) have a higher incidence of attention and learning problems in school than do their healthy peers. The present study tests the hypothesis that the psychostimulant methylphenidate (MPH) improves cognitive and social functioning among these patients. PATIENTS AND METHODS: We report on 83 long-term survivors of ALL and BT identified as having attentional deficits on behavioral testing and parent or teacher report, and problems with academic achievement. The 47 male and 36 female patients ranged from 0.6 to 14.3 years (median, 5.4 years) of age at diagnosis and 6.7 to 17.9 years (median, 11.9 years) of age at participation. The patients (40 ALL, 43 BT) participated in a randomized, double-blind, 3-week home cross-over trial of placebo (bid), low-dose MPH (0.3 mg/kg; maximum dose, 10 mg bid), and moderate-dose MPH (0.6 mg/kg; maximum dose, 20 mg bid). The primary end points were weekly teacher and parent reports on the Conners' Rating Scales and Social Skills Rating System. RESULTS: Compared to placebo, significant improvement with MPH was reported by teachers and parents on the Conners' Rating Scales and by teachers on the Social Skills Rating System. However, no consistent advantage of moderate dose over low dose was observed. Of those participating, 66 (79.5%) of the 83 patients continued on best clinical management. CONCLUSION: Treatment with MPH can at least temporarily reduce some attentional and social deficits among survivors of childhood ALL and BT. Long-term follow-up will reveal those subsets of patients who are more likely to benefit from MPH.

PMID: 15570081 [PubMed - in process]

Monday, December 06, 2004

"Mind Over Matter" - Wadsworth Center Brain-Computer Interface Project

This evening, the NBC Nightly News ran a feature report entitled "Mind Over Matter," concerning self-control over EEG components to "move" a computer cursor. The research program is the Wadsworth Center Brain-Computer Interface Project in Albany, New York. The report included an interview with the Project's Dr. Jonathan Wolpaw. Information about Dr Wolpaw and the project can be found on this webpage.


What's Happening in Neuroscience?

Yesterday's Sunday magazine in the Boston Globe included a decent feature article about advances in the neurosciences:
Brain Power
By Pamela Ferdinand
The Boston Globe
05 December 2004

[ ... Read the article ... ]

Sickle Cell Clinical Study Halted

Risk of Strokes Halts Sickle Cell Study
By Daniel Yee
Associated Press
The Washington Post
Monday, December 6, 2004; Page A02

ATLANTA, Dec. 5 -- A study aimed at determining whether some children with sickle cell anemia could be weaned off blood transfusion therapy has been halted because two young patients who stopped getting the procedure suffered strokes and others developed a high chance of strokes.

The National Institutes of Health decided to issue a clinical alert recommending that doctors continue with blood transfusions to reduce the risk of stroke among young sickle cell patients, even though the treatment has its own risk.

The study, called Stop II, was funded by the NIH's National Heart, Lung, and Blood Institute and involved 23 U.S. medical centers and two in Canada.

[ ... Read the full article ... ] (free registration required.)

Saturday, December 04, 2004

Business World: Biogen Idec, Elan, & Tysabri

There has been a lot of web searching for information about Tysabri (natalizumab) [formerly Antegren] in the wake of the FDA approval last month for use in multiple sclerosis. A lot of searching has been by patients and concerned family members, clinicians and students, and those interested in the business applications.

I posted a couple of entries about the drug approval that are found in the November archives. I've been looking for a business commentary to note and found one earlier today:

In the business-world end of this, here is an interesting commentary from the 24th of November by a writer for TheStreet.com:

What Price Tysabri?
By Adam Feuerstein
Senior Writer, TheStreet.com
11/24/2004 8:00 AM EST
Read the opinion article

Memory: In Search of What's Lost

From tomorrow's New York Times Sunday Magazine:
In Search of Lost Time
By CATHRYN JAKOBSON RAMIN

The New York Times
Published: December 5, 2004

A few months ago, as I trudged down the stairs of my office building, deep in my thoughts, I noticed a dark-haired woman waving to me from the window of her car. She looked vaguely familiar, but I couldn't place her. Like quite a few others, she had slipped out of my mental Rolodex. In my brain, the synaptic traces that connected us had frayed. Yet again, I had misplaced an entire human being.
[ ... Read the full article ... ]

Julia 1926 (Alzheimer Disease)

jill/txt describes her experience visiting this art display about a woman with Alzheimer disease. Read her blog entry here.

The Julia 1926 website can be found here.

Friday, December 03, 2004

Abstract of the Day: Neuropsychological Assessment

Sarno MT, Postman WA, Cho YS, Norman RG. Evolution of phonemic word fluency performance in post-stroke aphasia. Journal of Communication Disorders. 2005 Mar-Apr; 38(2): 83-107.

Department of Rehabilitation Medicine, School of Medicine, New York University, 400 East 34th Street, New York, NY 10016, USA.

In this longitudinal study, quantitative and qualitative changes in responses of people with aphasia were examined on a phonemic fluency task. Eighteen patients were tested at 3-month intervals on the letters F-A-S while they received comprehensive, intensive treatment from 3 to 12 months post-stroke. They returned for a follow-up evaluation at an average of 10 months post-intervention. Mean group scores improved significantly from beginning to end of treatment, but declined post-intervention. Patients produced a significantly greater number and proportion of modifiers (adjectives and adverbs) between the beginning and end of treatment, with no decline afterwards, implying that they had access to a wider range of grammatical categories over time. Moreover, patients used significantly more phonemic clusters in generating word lists by the end of treatment. These gains may be attributed to the combined effects of time since onset and the linguistic and cognitive stimulation that patients received in therapy. Learning outcomes: Readers of this paper should (1) gain a better understanding of verbal fluency performance in the assessment of aphasia, (2) recognize the importance of analyzing qualitative aspects of single word production in aphasia, and (3) contribute to their clinical judgment of long term improvement in aphasia.

PMID: 15571711 [PubMed - in process]

Progressive Multifocal Leukoencephalopathy

A Brown University press release describes a study published in this week's issue of Science:
Antipsychotic Drugs Stop Fatal Viral Infection In Brain Cells

PROVIDENCE, R.I. -- Generic antipsychotic drugs can protect brain cells from a virus that causes a fatal nervous system disorder, according to research conducted at Brown University and Case Western Reserve University.

The disorder, called progressive multifocal leukoencephalopathy or PML, affects hundreds of Americans with suppressed immune systems, including kidney transplant recipients, cancer patients undergoing chemotherapy and an estimated 4 percent of people with AIDS.

PML is caused by the JC virus, which destroys the cells that produce the fatty sheath that covers nerve cells. This causes dementia, vision loss, movement and speech impairment, paralysis and coma. The disorder is fast moving and fatal; Many patients die within four months after onset. PML is also on the rise. Due to the AIDS pandemic, incidence of the disorder rose 20-fold in the United States between 1979 and 1994, according to a study conducted by federal researchers.

But a team of scientists, led by Brown virologist Walter Atwood, has found that a handful of antipsychotic drugs can prevent brain cells from becoming infected by the JC virus. The drugs may prove to be an effective, ready-made therapy for PML prevention or treatment. Their results are published in the current issue of Science.

"This is very promising," Atwood said. "These are generic drugs we can take off the shelf that may help a lot of people."

"It is likely that there are many other drugs with none of the potential side effects of antipsychotic drugs that will also block infection," said co-author Bryan Roth, professor of biochemistry at the Case School of Medicine and director of the National Institute of Mental Health's Psychoactive Drug Screening Program.
[ ... Read the full press release ... ]

Thursday, December 02, 2004

Brain Surgery in the Early 1600s

As reported in the Boston Globe:
Skull fragment shows 400-year-old surgery in Va., researchers say
The Boston Globe
By Sonja Barisic, Associated Press
December 2, 2004

NORFOLK, Va. -- A skull fragment found in a nearly 400-year-old trash pit at Jamestown contains evidence of the earliest known surgery and possible autopsy in the English Colonies in America, researchers say.

Circular cut marks indicate someone attempted to drill two holes in the skull to relieve pressure on the brain, the researchers said. The patient, a European man, died and apparently underwent an autopsy.

Archeologists found the 4-inch-by-4-inch fragment this summer while digging in a bulwark trench on the site of James Fort. Jamestown, the first permanent English settlement in North America, was founded in 1607 as a business venture.

The skull piece was discarded with trash, such as pottery shards, from no later than about 1610, said Bly Straube, senior curator of the Association for the Preservation of Virginia Antiquities.
[ ... Read the full article ... ]

There Will Always Be Phineas

One of neuropsychology's and behavioral neuroscience's favorite historical case studies, Phineas Gage, is featured in this week's (02 December 2004) New England Journal of Medicine's "Images in Clinical Medicine" section, with two free-access .mpg videos by Peter Ratiu, M.D. and Ion-Florin Talos, M.D in their report, The Tale of Phineas Gage, Digitally Remastered.

Wednesday, December 01, 2004

Newsweek Cover Story: Memory Pharmacology

The cover story for the 06 December 2004 issue of Newsweek deals with developments in cognitive neuroscience and with drugs that may improve or enhance memory functioning:
The Quest for Memory Drugs
By Mary Carmichael
Newsweek
Dec. 6 issue - To say that Aplysia Californicus is one of nature's least glamorous beasts would be too kind. A hermaphroditic marine snail with mottled purple skin, it keeps to itself, responding to disturbances by emitting a murky fluid that stains the water around it. Its "brain," if you can call it that, is stunningly simple, with only a few thousand oversize neurons. It is not, in short, a likely candidate for glory in the animal kingdom. But a few years from now, much of the baby-boom generation may be greatly indebted to this unprepossessing little creature. Aplysia may look homely, but to scientists hoping to develop memory-enhancing medicine, it is a thing of beauty.
[ ... Read the full article ... ]

Monday, November 29, 2004

Radiologists Gather in Chicago

The 90th scientific conference of the Radiological Society of North America is meeting at this time, through the 3rd of December, in Chicago. Details of the meeting can be found on the Society's webpage for the conference.

Truth-Telling and the Brain

Can brain-imaging technologies show whether we are being truthful or not? A current study, reported by Reuters (as found on the Houston Chronicle website), takes a look:
Brain scans can tell who's lying, who's not
Reuters News Service
Nov. 29, 2004, 1:50PM

[snip]

"There may be unique areas in the brain involved in deception that can be measured with fMRI," said Dr. Scott Faro, director of the Functional Brain Imaging Center at Temple University School of Medicine in Philadelphia.

"There may be unique areas in the brain involved in truth-telling," Faro added at a news conference.

Faro and colleagues tested 10 volunteers. Six of them were asked to shoot a toy gun and then lie and say they didn't do it. Three others who watched told the truth about what happened. One volunteer dropped out of the study.

[snip]

There were clear differences between the liars and the truth-tellers, Faro's team told a meeting in Chicago of the Radiological Society of North America.

"We found a total of seven areas of activation in the deception (group)," he said. "We found four areas of activity in the truth-telling arm."

Overall, it seemed to take more brain effort to tell the lie than to tell the truth, Faro found.

Lying caused activity in the frontal part of the brain --- the medial inferior and pre-central areas, as well as the hippocampus and middle temporal regions and the limbic areas. Some of these are involved in emotional responses, Faro said.

During a truthful response, the fMRI showed activation of parts of the brain's frontal lobe, temporal lobe and cingulate gyrus.
[ ... Read the full article ... ]

Saturday, November 27, 2004

Upcoming Event: Boston, December 2004

The Massachusetts Neuropsychological Society is presenting a talk by Robert Stickgold, M.D. entitled "Sleep, Memory, and Dreams: A Neurocognitive Approach" on the 7th of December 2004 at 7:30 p.m. in the 8th Floor Conference Room of the Spaulding Rehabilitation Hospital.

Information about registration and fees can be found on the Society's website.

Soccer Headgear

On the topic of sports-related concussion, an article in today's New York Times on soccer headgear:

Soccer Headgear: Does It Do Any Good?
By JERE LONGMAN
The New York Times
27 November 2004

Read the article. (free registration required)

Friday, November 26, 2004

Issues in Clinical Trials: GDNF and Parkinson Disease

Today's New York Times includes a front-page article about the culture of clinical-trials research: what happens to participant subjects when an experimental drug is pulled from testing and, among other issues, how teasing apart placebo-based from drug-based improvements when a drug is pulled from study is impacted when participants swear by its effectiveness in their own experience?
Many See Hope in Parkinson's Drug Pulled From Testing
By ANDREW POLLACK
The New York Times
26 November 2004

With his condition deteriorating from Parkinson's disease last year, Steve Kaufman gave up making improvements to his home in Algonquin, Ill. "I couldn't even hold a nail stable," he recalled.

Earlier this year, after taking an experimental drug in a clinical trial, Mr. Kaufman built new kitchen cabinets and an outdoor deck. He was so steady he could walk across a narrow piece of lumber like an Olympic gymnast on the balance beam.

The drug, however, is no longer available to Mr. Kaufman or other Parkinson's patients in clinical trials. In June, its developer, Amgen, announced that the drug, which is called glial cell line-derived neurotrophic factor, or GDNF, had not proved better than a placebo. Two months later, the company said that safety issues had been discovered and it abruptly ordered all patients taken off the drug.

Amgen's move has provoked an outcry from patients who say the company is robbing them of their only hope. "It's almost the same thing as a diabetic losing their insulin," said Mr. Kaufman, who is 50 and has had Parkinson's for 10 years.

[ ... Read the full article ... ] (free registration required)

Abstract of the Day: Fatigue and Parkinson Disease

Alves G, Wentzel-Larsen T, Larsen JP. Is fatigue an independent and persistent symptom in patients with Parkinson disease? Neurology. 2004 Nov 23; 63(10): 1908-11.

Department of Neurology, Rogaland Central Hospital, Postboks 8100, N-4068 Stavanger, Norway.

OBJECTIVE: To evaluate if mental fatigue is a symptom that appears independently from other clinical features in patients with Parkinson disease (PD), and to study if fatigue is persistent over time in these patients. METHODS: In 1993, 233 patients with PD were included in a community-based study of fatigue and followed prospectively over 8 years. Fatigue was measured by a combination of a seven-point scale and parts of the Nottingham Health Profile (NHP) at baseline and after 4 and 8 years. In addition, the Fatigue Severity Scale (FSS) was used to evaluate fatigue in 2001. Population-averaged logistic regression models for correlated data were performed to study the relationship between fatigue and various demographic and clinical variables. RESULTS: In patients who were followed throughout the 8-year study period, fatigue increased from 35.7% in 1993 to 42.9% in 1997 and 55.7% in 2001. Fatigue was related to disease progression, depression, and excessive daytime sleepiness (EDS). However, the prevalence of fatigue in patients without depression and EDS remained high and increased from 32.1% to 38.9% during the study period. For about 44% of the patients with fatigue the presence of this symptom varied during the study period, as it was persistent in 56% of the patients with fatigue. CONCLUSIONS: The authors confirmed the high prevalence of mental fatigue in patients with Parkinson disease (PD). Fatigue is related to other non-motor features such as depression and excessive daytime sleepiness, but cannot be explained by this comorbidity alone. In more than half of the patients mental fatigue is persistent and seems to be an independent symptom that develops parallel to the progressive neurodegenerative disorder of PD.

PMID: 15557510 [PubMed - in process]

Tuesday, November 23, 2004

Multiple Sclerosis and Tysabri: FDA

From the FDA:

FOR IMMEDIATE RELEASE
P04-107
November 23, 2004
Full press release
Media Inquiries: 301-827-6242
Consumer Inquiries: 888-INFO-FDA

First Monoclonal Antibody Treatment For Multiple Sclerosis Approved

FDA today licensed a new biologic approach to treat patients with relapsing forms of multiple sclerosis (MS) to reduce the frequency of symptom flare-ups or exacerbations of the disease. MS is a chronic, often disabling disease of the brain and spinal cord.

Natalizumab, the new product, is a monoclonal antibody bioengineered from part of a mouse antibody to closely resemble a human antibody. It is being marketed under the tradename Tysabri. The product is given intravenously once a month in a physician's office.

[ ... continues ... ]

The BrainPort and Sensory Substitution

From today's New York Times:
New Tools to Help Patients Reclaim Damaged Senses
By SANDRA BLAKESLEE
The New York Times
23 November 2004
Full article (free registration required)

[snippet]

But the technology for swapping sensory information is largely the effort of Dr. Paul Bach-y-Rita, a neuroscientist in the University of Wisconsin Medical School's orthopedics and rehabilitation department. More than 30 years ago, Dr. Bach-y-Rita developed the first sensory substitution device, routing visual images, via a head-mounted camera, to electrodes taped to the skin on people's backs. The subjects, he found, could "see" large objects and flickering candles with their backs. The tongue, sensitive and easy to reach, turned out to be an even better place to deliver substitute senses, Dr. Bach-y-Rita said.

Until recently sensory substitution was confined to the laboratory. But electronic miniaturization and more powerful computer algorithms are making the technology less cumbersome. Next month, the first fully portable device will be tested in Dr. Bach-y-Rita's lab.

The BrainPort is nearing commercialization. Two years ago, the University of Wisconsin patented the concept and exclusively licensed it to Wicab Inc., a company formed by Dr. Bach-y-Rita to develop and market BrainPort devices. Robert Beckman, the company president, said units should be available a year from now.

Multiple Sclerosis and Antegren/Tysabri

From the CBC:
Health Canada fast tracks review of multiple sclerosis drug
Last Updated Mon, 22 Nov 2004 21:28:46 EST

TORONTO - Some Canadians with multiple sclerosis are encouraged by the early results of a study on a new kind of treatment for the disease.

The drug Antegren prevents white blood cells from migrating to the central nervous system and flooding the brain, where the cells can cause damage.

The study included 942 patients with relapsing-remitting MS, the earliest phase of the disease.

After one year, patients on Antregen had two-thirds fewer relapses or attacks compared to patients given a placebo.

"In general, you can say that this is the greatest therapeutic effects ever seen in year one for a trial of a multiple sclerosis drug," said Dr. Paul O'Connor, the lead Canadian investigator for the trial.
[ ... Read the full report ... ]
From the elan company website: Antegren/Tysabri (natalizumab).

Monday, November 22, 2004

Memories and Memories

From a press release earlier today from Toronto's Baycrest Centre for Geriatric Care:
What happens in the brain when we remember our own past?

Toronto, CANADA --Researchers are using functional magnetic resonance imaging (fMRI) to probe brain activity in search of the answer. According to a new fMRI study using a "diary" method to collect memories, it all depends on what we're thinking about!

Researchers have known for decades that thinking about autobiographical facts is different from thinking about autobiographical episodes that happened only once. Since both kinds of thoughts can occur at the same time when people talk about their past, researchers have struggled to find an effective way to separate them.

The new study, published in the current issue of the Journal of Cognitive Neuroscience (16:9), is the first brain imaging study of its kind to use diary-like memories collected by volunteers. It was led by The Rotman Research Institute at Baycrest Centre for Geriatric Care.

Over a period of several months prior to the brain scan, volunteers documented dozens of unique events from their personal lives on a micro cassette recorder (episodic memories). At the same time, they recorded statements about personal facts of their lives (semantic memories). The researchers played these recordings back to the volunteers while their brains were being scanned with fMRI.

The results showed that the two types of autobiographical memory engaged different parts of the brain, even when the memories concerned the same contents. For example, the semantic thought "Every Friday afternoon I take the dog for a long walk" produced brain activity in one set of regions, whereas the episodic thought "One Friday afternoon my dog got away and I spent 45 minutes running after him" produced brain activity in a different set of regions.

"Although both kinds of memory are autobiographical, they serve very different purposes," says lead investigator Dr. Brian Levine, a senior scientist with The Rotman Research Institute at Baycrest and associate professor in Psychology and Neurology, University of Toronto. "Factual autobiographical memory grounds us in time and gives continuity to our lives. Episodic autobiographical memory allows us to travel in time, to relive our past."
[ ... Read the full press release ... ]

Thursday, November 18, 2004

Ultrasound and TPA Combined Treatment for Stroke

This evening, the CBC news show The National reported on a study newly published in the New England Journal of Medicine. Part of the CBC website report follows, followed by a link to the study's abstract:
Ultrasound may improve stroke treatment
CBC
Last Updated Thu, 18 Nov 2004 21:48:52 EST

EDMONTON - Ultrasounds break up blood clots in the brain and may help to treat strokes, new research performed at Canadian hospitals suggests.

A stroke occurs when a clot blocks a blood vessel and cuts off circulation. Doctors give a drug called TPA by intravenous to dissolve blood clots lodged in the brain.

Dr. Maher Saqqur of the University of Alberta and his colleagues tested an experimental combination of TPA and ultrasound to treat stroke before brain tissues are starved of a blood supply.

"What we find is that patients who receive the TPA plus the ultrasound do well compared to patients who get the TPA just by themselves," said Saqqur.

The study looked at 126 patients. After three months, 42 per cent of patients who received the experimental treatment were fully recovered, compared to 30 per cent who had TPA alone.

The risk of bleeding in the brain appeared to be small and about the same as with TPA alone, the team reported in Thursday's issue of The New England Journal of Medicine.

Vibrations from the high-intensity ultrasound waves may help to mix the drug or help TPA to stick to the clot better, the researchers speculate.
[ ... Read the full article ... ]

Here is the NEJM reference:

Andrei V. Alexandrov et al. Ultrasound-enhanced systemic thrombolysis for acute ischemic stroke. New England Journal of Medicine. 2004; 351: 2170-2178.

Googling For Academic Medical Research

Google has announced and is online (beta version) with an academic search engine called "Google Scholar" - which "enables you to search specifically for scholarly literature, including peer-reviewed papers, theses, books, preprints, abstracts and technical reports from all broad areas of research. Use Google Scholar to find articles from a wide variety of academic publishers, professional societies, preprint repositories and universities, as well as scholarly articles available across the web."

http://scholar.google.com

About Google Scholar
http://scholar.google.com/scholar/about.html

Google Scholar FAQs
http://scholar.google.com/scholar/about.html#faq

Executive Functions in a Fictional West Wing

In the excellent Blue Stater fictional world of the administration of President Jed Bartlet on NBC’s The West Wing, a brief reference to brain-behavior functions played a minor plotline in this evening’s episode as the former Chief of Staff Leo McGarry reminds the new Chief of Staff C.J. Cregg to get the President to play chess with her at least once a week. This advisement is left as is until the end of the episode, when Leo reveals that this was his subtle way to attempt to discern whether the President’s “executive functions” were showing some degree of impairment. (For those new to the show, the President was diagnosed with multiple sclerosis prior to his first administration but did not reveal it publically until the time before his run for re-election several years ago).

“Executive functions” are a specific set of higher order brain functions that have been the subject of much neuroscientific interest for many years now. There are many good references that an interested person could access to learn about these neuropsychological functions in detail.

Here is a link to the abstract of one such study, published back in 1997:

J Foong, L Rozewicz, G Quaghebeur, CA Davie, LD Kartsounis, AJ Thompson, DH Miller and MA Ron. Executive function in multiple sclerosis: The role of frontal lobe pathology. Brain. 1997; 120(1): 15-26.

Tuesday, November 16, 2004

Abstract of the Day: Dementia

Starkstein SE, Garau ML, Cao A. Prevalence and clinical correlates of disinhibition in dementia. Cogn Behav Neurol. 2004 Sep; 17(3): 139-47.

School of Psychiatry and Clinical Neurosciences, University of Western Australia, and Fremantle Hospital, Fremantle, Australia.

OBJECTIVE AND METHODS: The phenomenology, main clinical correlates, and long-term evolution of disinhibition in dementia are not well known. To examine this issue, we studied a consecutive series of 272 patients with probable Alzheimer disease using a comprehensive psychiatric and neuropsychological evaluation that included the Disinhibition Scale. A subset of patients was reexamined with the same instruments between 1 and 4 years after the initial evaluation. RESULTS: A factor analysis of the Disinhibition Scale demonstrated 4 factors: (1) abnormal motor behavior, (2) hypomania, (3) loss of insight and egocentrism, and (4) poor self-care. Disinhibition was significantly associated with major and dysthymic depression, more severe negative symptoms, and loss of awareness. Most patients with disinhibition at the initial evaluation still showed disinhibition at follow-up, whereas 23% of patients without disinhibition at the initial evaluation developed disinhibition at follow-up. CONCLUSIONS: Disinhibition is a frequent and long-lasting problem in dementia. Our study demonstrates that the construct of disinhibition consists of 4 independent subsyndromes, each of which may have specific underlying mechanisms.

PMID: 15536301 [PubMed - in process]

Saturday, November 13, 2004

Abstract of the Day: Neuropsychological Assessment

Radanovic M, Mansur LL, Scaff M. Normative data for the Brazilian population in the Boston Diagnostic Aphasia Examination: Influence of schooling. Braz J Med Biol Res. 2004 Nov;v37(11): 1731-8. Epub 2004 Oct 26.

In Neurolinguistics, the use of diagnostic tests developed in other countries can create difficulties in the interpretation of results due to cultural, demographic and linguistic differences. In a country such as Brazil, with great social contrasts, schooling exerts a powerful influence on the abilities of normal individuals. The objective of the present study was to identify the influence of schooling on the performance of normal Brazilian individuals in the Boston Diagnostic Aphasia Examination (BDAE), in order to obtain reference values for the Brazilian population. We studied 107 normal subjects ranging in age from 15 to 84 years (mean +/- SD = 47.2 +/- 17.6 years), with educational level ranging from 1 to 24 years (9.9 +/- 4.8 years). Subjects were compared for scores obtained in the 28 subtests of the BDAE after being divided into groups according to age (15 to 30, N = 24, 31 to 50, N = 33 and 51 years or more, N = 50) and education (1 to 4, N = 26, 5 to 8, N = 17 and 9 years or more, N = 61). Subjects with 4 years or less of education performed poorer in Word Discrimination, Visual Confrontation Naming, Reading of Sentences and Paragraphs, and Primer-Level Dictation (P lt 0.05). When breakdown by schooling was 8 years or less, subjects performed poorer in all subtests (P lt 0.05), except Responsive Naming, Word Recognition and Word-Picture Matching. The elderly performed poorer (P lt 0.05) in Complex Ideational Material, Visual Confrontation Naming, Comprehension of Oral Spelling, Written Confrontation Naming, and Sentences to Dictation. We present the reference values for the cut-off scores according to educational level.

PMID: 15517090 [PubMed - in process]

Friday, November 12, 2004

Language Development

Nature Reviews Neuroscience offers the full text (HTML and .pdf) of this interesting overview to language development in its November issue:

Patricia K. Kuhl. Early language acquisition: Cracking the speech code. Nature Reviews Neuroscience 2004. 5: 831-843.

Institute for Learning and Brain Sciences and the Department of Speech and Hearing Sciences, University of Washington, Seattle, Washington 98195, USA.

Infants learn language with remarkable speed, but how they do it remains a mystery. New data show that infants use computational strategies to detect the statistical and prosodic patterns in language input, and that this leads to the discovery of phonemes and words. Social interaction with another human being affects speech learning in a way that resembles communicative learning in songbirds. The brain's commitment to the statistical and prosodic patterns that are experienced early in life might help to explain the long-standing puzzle of why infants are better language learners than adults. Successful learning by infants, as well as constraints on that learning, are changing theories of language acquisition.

(doi:10.1038/nrn1533)

In The Weeklies

Here are some relevant highlights from this week’s major scientific and medical weeklies:

Journal of the American Medical Association
10 November 2004
The current issue includes the paper: Kristine Yaffe et al. The Metabolic Syndrome, Inflammation, and Risk of Cognitive Decline. JAMA. 2004; 292: 2237-2242.

New England Journal of Medicine
11 November 2004
This week’s issue includes a book review of an edited book by Nalin Gupta, Anuradha Banerjee, and Daphne Haas-Kogan: Pediatric CNS Tumors.

Lancet
13 November 2004
This week’s issue includes the research paper The United Kingdom Infantile Spasms Study comparing vigabatrin with prednisolone or tetracosactide at 14 days: A multicentre, randomised controlled trial by Andrew L Lux and colleagues.

Science
12 November 2004
This week’s issue includes several news reports from the recent Society for Neuroscience annual meeting.

Abstract of the Day: Alzheimer Disease

Atchison TB, Bradshaw M, Massman PJ. Investigation of profile difference between Alzheimer's disease patients declining at different rates: Examination of baseline neuropsychological data. Archives of Clinical Neuropsychology. 2004 Dec; 19(8): 1007-1015.

Department of Psychology, University of Houston, USA.

The rate of cognitive decline in AD has been noted to vary significantly among patients. The ability to predict the probable rate of decline early in the disease process would be of great practical importance. Attempts to analyze early cognitive deficits to find patterns associated with rapid decline have met with limited success. This paper utilized a large sample of patients with a diagnosis of probable AD evaluated longitudinally in ongoing research at the ADRC at Baylor College of Medicine and a statistical procedure of profile analysis to assess the initial data for a pattern associated with rapid decline. The findings indicated that despite initial equality of MMSE scores, patients showing rapid MMSE decline at one year displayed significantly more impaired performance on neuropsychological measures at diagnosis. Discussion includes discussion on the use of the MMSE for tracking general cognitive function and the difficulties of ascertaining stable profiles for prediction.

PMID: 15533693 [PubMed - as supplied by publisher]

Wednesday, November 10, 2004

Upcoming Event: Seattle, November 2004

The 24th Annual Conference of the National Academy of Neuropsychology (NAN) will be held in Seattle, Washington from the 17th of November through the 20th. The conference will take place at the Westin Seattle. Information about the conference program and registration can be found at the NAN Conferences webpage.

Monday, November 08, 2004

Neonatal Brain Injury

The 04 November 2004 issue of the New England Journal of Medicine has a useful review article about neonatal brain injury in its Medical Progress section:

Donna M. Ferriero. Neonatal brain injury. New England Journal of Medicine 2004. 351(19): 1985-1995.

Topics include hypoxic–ischemic encephalopathy and neonatal stroke.

Sunday, November 07, 2004

Damasios to be Awarded Jean-Louis Signoret Prize

From this past Wednesday's Iowa City Press-Citizen:
Damasio couple wins prestigious prize
By the Press-Citizen
03 November 2004

Two physicians from the University of Iowa will receive an important honor at a ceremony Nov. 15 in the Salpetrière Hospital in Paris, France.

UI Roy J. and Lucille A. Carver College of Medicine faculty members Antonio Damasio, M.D., Ph.D., the M.W. Van Allen Professor and Head of the UI Department of Neurology, and Hanna Damasio, M.D., Distinguished Professor of Neurology and director of the Human Neuroanatomy and Neuroimaging Laboratory, will receive the Jean-Louis Signoret Prize in Cognitive Neuroscience. La Fondation Ipsen sponsors the prize.

The international jury cited the contributions of the Damasios to the neurobiological understanding of social cognition. This marks the first time that two investigators will share the prize. Previous recipients of the prestigious honor include neuroscientists Eric Kandel of Columbia University and Jean-Pierre Changeux of Institut Pasteur.
[ ... Read the full article ... ]

Thursday, November 04, 2004

Cerebral Palsy, Periventricular Leukomalacia, and Infections

A number of news sites are providing coverage of a study published in the current issues of The American Journal of Obstetrics & Gynecology. Here is a version of the coverage from the New York Times:
New Evidence on Main Cause of Cerebral Palsy
By NICHOLAS BAKALAR
The New York Times
Published: November 2, 2004

A new study undermines the long-held belief among obstetricians that oxygen deprivation, or hypoxia, is the main cause of cerebral palsy in premature infants.

The study, published in the October issue of The American Journal of Obstetrics & Gynecology, found that the brain injury that leads to cerebral palsy was much more commonly associated with infection than with hypoxia.

The new findings, said Dr. Ernest Graham, an assistant professor in the department of obstetrics and gynecology at Johns Hopkins and the lead author of the study, have important implications for both research and clinical practice.

"This changes our thinking," Dr. Graham said. "In the past, we've focused primarily on hypoxia," but the study suggests that monitoring for hypoxia "isn't likely to help very much."

Finding ways to prevent and treat infections, on the other hand, "may have a huge impact on the problem," he said.

[ ... Read the full article ... ] (free registration required)

Monday, November 01, 2004

Alzheimer Disease: Behavioral Manifestations

From tomorrow's New York Times:
Alzheimer's Steals More Than Memory
By DENISE GRADY
The New York Times
02 November 2004

It happened without warning, early one day last summer as they prepared to go out. Gloria Rapport's husband raised his arm to her, fist poised.

"He was very close to striking me," she said.

What had provoked him? "Nothing," she said. "I asked him to get in the car."

Mrs. Rapport's husband, Richard, 71, has Alzheimer's disease. His forgetfulness and confusion began about nine years ago, not long after they married. More recently, emotional troubles have loomed. Anxiety came first: he suddenly feared being left alone in the house. Outbursts of anger followed. The man she had always known to be kind and gentle could in an instant turn "cunning, nasty, aggressive, menacing," she said.

“The behavioral changes I've seen are absolutely frightening," she said. "I understand now why so many families institutionalize someone, because I was afraid of him."
[ ... Read the full article ... ]

Saturday, October 30, 2004

In The Weeklies

Here are some relevant highlights from this week’s major scientific and medical weeklies:

New England Journal of Medicine
28 October 2004

This week’s issue includes several papers of interest, two on the topic on bacterial meningitis and the third is a case study of a patient with a frontal lobe lesion: Bacterial Meningitis — A View of the Past 90 Years by M. N. Swartz; Clinical Features and Prognostic Factors in Adults with Bacterial Meningitis by D. van de Beek and colleagues; and Case 33-2004 — A 34-Year-Old Man with a Seizure and a Frontal-Lobe Brain Lesion by E. N. Eskandar and colleagues.

Science
29 October 2004

This week’s issue includes a research study that has been reported in quite a few public media outlets over the past few days in terms of the relation between stress and forgetfulness. Here is the abstract:
Birnbaum SG, Yuan PX, Wang M, Vijayraghavan S, Bloom AK, Davis DJ, Gobeske KT, Sweatt JD, Manji HK, Arnsten AF. Protein kinase C overactivity impairs prefrontal cortical regulation of working memory. Science. 2004 Oct 29; 306(5697): 882-4.

Department of Neurobiology, Yale Medical School, 333 Cedar Street, New Haven, CT 06520-8001, USA.

The prefrontal cortex is a higher brain region that regulates thought, behavior, and emotion using representational knowledge, operations often referred to as working memory. We tested the influence of protein kinase C (PKC) intracellular signaling on prefrontal cortical cognitive function and showed that high levels of PKC activity in prefrontal cortex, as seen for example during stress exposure, markedly impair behavioral and electrophysiological measures of working memory. These data suggest that excessive PKC activation can disrupt prefrontal cortical regulation of behavior and thought, possibly contributing to signs of prefrontal cortical dysfunction such as distractibility, impaired judgment, impulsivity, and thought disorder.

PMID: 15514161 [PubMed - in process]

Friday, October 29, 2004

Laser-Based Neural Stimulation

A press release from Vanderbilt University discusses research seeking to develop more precise ways to stimulate individual neurons through the use of laser light:

Stimulating Nerve Cells with Laser Precision

Newswise — Biomedical engineers and physicians at Vanderbilt University have brought the day when artificial limbs will be controlled directly by the brain considerably closer by discovering a method that uses laser light, rather than electricity, to stimulate and control nerve cells.

The researchers have discovered that low-intensity infrared laser light can spark specific nerves to life, exciting a leg or even individual toes without actually touching the nerve cells.

“This technique brings nerve stimulation out of the Dark Ages,” said Vanderbilt Assistant Professor of Biomedical Engineering and Neurological Surgery Anita Mahadevan-Jansen. “Much work is going on around the world trying to make electric nerve stimulation better, but the technique is inherently limited. Using lasers instead, we can simultaneously excite and record the responses of nerve fibers with much greater precision, accuracy and effectiveness.”

The method was developed by Mahadevan-Jansen; her husband Duco Jansen, associate professor of biomedical engineering and neurological surgery; Dr. Peter Konrad and Dr. Chris Kao of Vanderbilt Neurological Surgery, both assistant professors of neurological surgery; and biomedical engineering doctoral student Jonathon Wells.

In an experiment with rats, the scientists used a laser to stimulate the sciatic nerve and to control muscles in the animal’s hind leg and individual toes, demonstrating accuracy beyond the limitations of electrical stimulation. Immediately following the experiment, the rats regained full use of their legs with no signs of weakness or damage.

Konrad, who is also director of the Vanderbilt Functional Neurosurgery program, points out that neurostimulation is ideally done cell by cell. “The problem with the conventional electrical method is that we have a large zone around our target neuron that also is affected simply because of the way electricity travels throughout the tissue. Using light to stimulate neurons, we can pick off a single neuron without affecting the other neurons around it.”

[ ... Read the full press release ... ]

Thursday, October 28, 2004

Abstract of the Day: Lobar Neurodegeneration

Gorno-Tempini ML, Rankin KP, Woolley JD, Rosen HJ, Phengrasamy L, Miller BL. Cognitive and behavioral profile in a case of right anterior temporal lobe neurodegeneration. Cortex. 2004 Sep-Dec; 40(4-5): 631-44.

University of California San Francisco Department of Neurology, San Francisco, CA, USA.

Semantic dementia (SD) is a clinical variant of frontotemporal lobar degeneration (FTLD) characterized by progressive deterioration of semantic memory with relative sparing of other cognitive functions. It is associated with mainly left anterior temporal atrophy, and is also referred to as "left-temporal lobe variant" of FTLD. Recently, patients with mainly right-sided atrophy, or "right-temporal lobe variant"(RTLV), have been described. While some authors have reported that the initial and most significant deficit in these right-sided cases is a difficulty in recognizing famous people, others have observed that major behavioral abnormalities are the presenting symptoms. Here we report a detailed neuropsychological, language, behavioral and neuroimaging assessment of JT, a case of right temporal lobe variant of FTLD. JT showed early and prominent behavioral changes accompanied by a severe impairment in recognizing foods by their look, flavor or name. Later she also developed a difficulty in recognizing familiar people and objects. Standardized caregiver questionnaires of JT's pre- and post-morbid personality and interpersonal functioning showed that she went from being a flexible, dominant, extraverted, person to showing rigid, submissive and introverted behaviors. Her levels of neuroticism significantly increased, while her scores on agreeableness and cognitive and emotional empathy dropped. Voxel-based morphometry (VBM) showed most significant atrophy in the right amygdala/anterior hippocampal complex and collateral sulcus, extending to the right insula. We discuss the atypical cognitive and behavioral features of this case of RTLV of FTLD and stress the importance of behavioral changes and atypical semantic deficits for early diagnosis.

PMID: 15505973 [PubMed - in process]

Business World: EMD 281014 and Insomnia

From the New York Times website:

Lilly to Buy Insomnia Compound
By THE ASSOCIATED PRESS
Published: October 28, 2004
Filed at 11:21 a.m. ET

INDIANAPOLIS (AP) -- Eli Lilly and Co. will pay a German pharmaceutical company $29 million for the rights to an experimental compound the Indianapolis-based drug maker hopes can become its first product to treat insomnia.

The compound, discovered by Merck KGaA, has the potential to be a new way to treat sleep disorder, without being addictive or causing unwelcome side effects, said Darryle D. Schoepp, vice president of neuroscience discovery research at Lilly.

"This could be really a very important medical advance in the treatment of sleep disorders,'" he said Wednesday.

In addition to purchasing the compound, Lilly will make milestone payments to Merck as the drug moves through testing, plus pay royalties on any sales. Merck keeps rights to co-promote the compound in certain countries.

Called EMD 281014, the molecule has undergone the first stage of human testing -- tests that showed it is safe in humans, Schoepp said.

[ ... Read the full article ... ]. (free registration required)

Parkinson's Disease

The CBS show "60 Minutes Wednesday" aired a piece last evening, A Hole in His Head, which accounts the story of one person's pallidotomy in 1995 and visits with him again in 2004. From CBS:
Parkinson's disease is a heartbreaking illness that causes frozen, stone-faced stillness in those afflicted. Correspondent Morley Safer reports on the story of one man, Fred Amphlett of Bristol, England, who had been a prisoner of Parkinson's for years.

When Safer first met him in 1995, he was about to undergo an operation called a pallidotomy, once used by doctors to ease the agonies of Parkinson's. It was not a cure, nor was it for everyone. But for Amphlett, it was his last hope.
[ ... Read the full transcript ... ]

Wednesday, October 27, 2004

Monkey "Closed Loop" Manipulation

From Wired News, another presentation from Neuroscience 2004:
Advent of the Robotic Monkeys
By David Cohn
01:00 PM Oct. 26, 2004 PT Wired News

If a monkey is hungry but has his arms pinned, there's not much he can do about it. Unless that monkey can control a nearby robotic arm with his brain.

And that's exactly what the monkey in Andrew Schwartz 's neurobiology lab at the University of Pittsburgh can do, feeding himself using a prosthetic arm controlled solely by his thoughts.

If mastered, the technology could be used to help spinal cord injuries, amputees or stroke victims. "I still think prosthetics is at an early stage ... but this is a big step in the right direction," said Chance Spalding, a bioengineering graduate student who worked on the project.

[snip]

The unique aspect of Schwartz's research is that he conducted what is known as "closed loop" brain experiments. In a "closed loop" experiment, the monkey is conscious of the robotic arm and is making an effort to control it. Monkeys in previous experiments did not understand that they were having an effect on the world at all. Duke University performed such prosthetic arm experiments as far back as 2000. In one case they even sent the electrode signals over the internet , allowing the monkey to move an arm 600 miles away at MIT.

"The open loop experiment was really very crude," said Schwartz. "The closed loop introduces us into a whole new field because the animal actually sees the arm and the consequence of what it is doing." For Schwartz's monkey the robotic arm is incorporated into its mental body representation, making it an extra limb.

[ ... Read the full report ... ]

Tuesday, October 26, 2004

Business World: Vasogen and Parkinson's Disease

A company press release concerning a presentation at Neuroscience 2004:
Vasogen's VP025 Provides a Neuroprotective Effect in Preclinical Model of Parkinson's Disease

TORONTO, Oct. 26 /PRNewswire-FirstCall/ - Vasogen Inc. (NASDAQ:VSGN; TSX:VAS), a researcher and developer of immune modulation therapies targeting chronic inflammation, today announced the presentation of preclinical research demonstrating the ability of VP025 to provide a significant neuroprotective effect in a model of Parkinson's disease. The research, carried out by the Department of Anatomy/Neuroscience, Biosciences Institute, University College Cork, Ireland, was presented at Neuroscience 2004, the Society for Neuroscience's 34th Annual Meeting in San Diego.

"The ability of VP025 to offer a protective effect in the brain and reduce neuron death in this preclinical model suggests that this drug may have potential in the treatment of Parkinson's disease," said Dr. Aideen Sullivan, principal investigator for this study at University College Cork. "It is also encouraging to note that these data are consistent with other research being presented at this conference this week, which highlight the positive anti-inflammatory effects of VP025 in other preclinical models."

[ ... Read the full press release ... ]

Sunday, October 24, 2004

Olfactory Bulb Stem Cell Transplants and ALS

A number of news reports are beginning to be published from presentations at Neuroscience 2004, the ongoing conference of the Society for Neuroscience. Here is one press release from Johns Hopkins Medical Institutions concerning a presentation about amyotrophic lateral sclerosis (ALS):
Olfactory Bulb Stem Cells and Lou Gehrig's Disease
Johns Hopkins researchers have found that transplants of mouse stem cells taken from the adult brain's olfactory bulb can delay symptoms and death in a mouse model of amyotrophic lateral sclerosis, or Lou Gehrig's disease.
Read the abstract for Transplantation of Adult Olfactory Bulb Neural Stem Cells Delays Disease Onset and Prolongs Survival in a Mouse ALS Model by L.J. Martin and Z. Liu.

[ ... Read the full press release ... ]

Friday, October 22, 2004

In The Weeklies

Here are some relevant highlights from this week’s major scientific and medical weeklies:

Journal of the American Medical Association
20 October 2004
This week’s JAMA has a number of contributions on the subject of the diagnosis and treatment of strokes.

New England Journal of Medicine
21 October 2004
This week’s issue contains a research paper and an editorial on the topic of Tuberculous meningitis: Abstract for Dexamethasone for the Treatment of Tuberculous Meningitis in Adolescents and Adults by Thwaites and colleagues and an extract of the editorial, Adjunctive Steroids for Tuberculous Meningitis - More Evidence, More Questions by Quagliarello.

Lancet
23 October 2004
The current issue includes the paper, Interferon beta-1a for brain tissue loss in patients at presentation with syndromes suggestive of multiple sclerosis: A randomised, double-blind, placebo-controlled trial by Filippi and colleagues.

Science
22 October 2004
This week’s issue has a special topical theme, gene expression.

It includes the report, A Chromosome 21 Critical Region Does Not Cause Specific Down Syndrome Phenotypes, by L. E. Olson, J. T. Richtsmeier, J. Leszl, and R. H. Reeves (pp. 687-690) and a perspective, The Critical Region in Trisomy 21, by D. L. Nelson and R. A. Gibbs (pp. 619-621).

Nature
21 October 2004
This week’s Nature includes the letter, Neural correlates of mental rehearsal in dorsal premotor cortex, by P. Cisek and J. F. Kalaska, excerpted below:

"Behavioural and imaging studies suggest that when humans mentally rehearse a familiar action they execute some of the same neural operations used during overt motor performance. Similarly, neural activation is present during action observation in many of the same brain regions normally used for performance, including premotor cortex. Here we present behavioural evidence that monkeys also engage in mental rehearsal during the observation of sensory events associated with a well-learned motor task. Furthermore, most task-related neurons in dorsal premotor cortex exhibit the same activity patterns during observation as during performance, even during an instructed-delay period before any actual observed motion. This activity might be a single-neuron correlate of covert mental rehearsal."

Neuroscience 2004 Conference Begins Tomorrow

Neuroscience 2004, the Society For Neuroscience's 34th Annual Meeting, begins in San Diego tomorrow and continues until Wednesday, the 27th. To read more about the conference and the Society, click here.

Wednesday, October 20, 2004

Imaging in the Initial Evaluation of Acute Stroke Symptoms

This week's free access full-text paper in the new issue of the Journal of the American Medical Association addresses the relative value of CT vs. MRI imaging in the initial evaluation of acute CVA symptoms. Click here for the full paper; the abstract follows:

Chelsea S. Kidwell, MD; Julio A. Chalela, MD; Jeffrey L. Saver, MD; Sidney Starkman, MD; Michael D. Hill, MD; et al. Comparison of MRI and CT for Detection of Acute Intracerebral Hemorrhage. JAMA. 2004; 292: 1823-1830.

ABSTRACT

Context.  Noncontrast computed tomography (CT) is the standard brain imaging study for the initial evaluation of patients with acute stroke symptoms. Multimodal magnetic resonance imaging (MRI) has been proposed as an alternative to CT in the emergency stroke setting. However, the accuracy of MRI relative to CT for the detection of hyperacute intracerebral hemorrhage has not been demonstrated.

Objective.  To compare the accuracy of MRI and CT for detection of acute intracerebral hemorrhage in patients presenting with acute focal stroke symptoms.

Design, Setting, and Patients.  A prospective, multicenter study was performed at 2 stroke centers (UCLA Medical Center and Suburban Hospital, Bethesda, Md), between October 2000 and February 2003. Patients presenting with focal stroke symptoms within 6 hours of onset underwent brain MRI followed by noncontrast CT.

Main Outcome Measures.  Acute intracerebral hemorrhage and any intracerebral hemorrhage diagnosed on gradient recalled echo (GRE) MRI and CT scans by a consensus of 4 blinded readers.

Results.  The study was stopped early, after 200 patients were enrolled, when it became apparent at the time of an unplanned interim analysis that MRI was detecting cases of hemorrhagic transformation not detected by CT. For the diagnosis of any hemorrhage, MRI was positive in 71 patients with CT positive in 29 (P less than .001). For the diagnosis of acute hemorrhage, MRI and CT were equivalent (96% concordance). Acute hemorrhage was diagnosed in 25 patients on both MRI and CT. In 4 other patients, acute hemorrhage was present on MRI but not on the corresponding CT—each of these 4 cases was interpreted as hemorrhagic transformation of an ischemic infarct. In 3 patients, regions interpreted as acute hemorrhage on CT were interpreted as chronic hemorrhage on MRI. In 1 patient, subarachnoid hemorrhage was diagnosed on CT but not on MRI. In 49 patients, chronic hemorrhage, most often microbleeds, was visualized on MRI but not on CT.

Conclusion.  MRI may be as accurate as CT for the detection of acute hemorrhage in patients presenting with acute focal stroke symptoms and is more accurate than CT for the detection of chronic intracerebral hemorrhage.

Tuesday, October 19, 2004

When is it Good to Forget?

Anyone who's seen the movie, Eternal Sunshine of the Spotless Mind, has thought about the question. Many may be surprised that a number of neuroscientists and drug developers have been asking the same question. The issue comes up when thinking of the topic of so-called "cosmetic neurology," but also arises when considering very serious acute mental trauma. Today's Washington Post includes an article exploring this question:
Is Every Memory Worth Keeping?
Controversy Over Pills to Reduce Mental Trauma

By Rob Stein
Washington Post Staff Writer
Tuesday, October 19, 2004; Page A01

[snip]

Proponents say it could lead to pills that prevent or treat PTSD in soldiers coping with the horrors of battle, torture victims recovering from brutalization, survivors who fled the World Trade Center on Sept. 11, 2001, and other victims of severe, psychologically devastating experiences.

"Some memories can be very disruptive. They come back to you when you don't want to have them -- in a daydream or nightmare or flashbacks -- and are usually accompanied by very painful emotions," said Roger K. Pitman, a professor of psychiatry at Harvard Medical School who is studying the approach. "This could relieve a lot of that suffering."

Skeptics, however, argue that tinkering with memories treads into dangerous territory because memories are part of the very essence of a person's identity, as well as crucial threads in the fabric of society that help humanity avoid the mistakes of the past.

"All of us can think of traumatic events in our lives that were horrible at the time but made us who we are. I'm not sure we'd want to wipe those memories out," said Rebecca S. Dresser, a medical ethicist at Washington University in St. Louis who serves on the President's Council on Bioethics, which condemned the research last year. "We don't have an omniscient view of what's best for the world."

Some fear anything designed for those severely disabled by psychic damage will eventually end up being used far more casually -- to, perhaps, forget a bad date or a lousy day at work.

"You can easily imagine a scenario of 'I was embarrassed at my boss's party last night, and I want to take something to forget it so I can have more confidence when I go into the office tomorrow,' " said David Magnus, co-director of Stanford University's Center for Biomedical Ethics. "It's not hard to imagine that it will end up being used much more broadly."

[snip]

[ ... Read the full article ... ]

Neuromarketing: Brand Loyalty and the Brain

Last week's news had several reports about a new functional MRI study looking at taste preferences and brand loyalty. Here is the abstract of that study:
McClure SM, Li J, Tomlin D, Cypert KS, Montague LM, Montague PR. Neural correlates of behavioral preference for culturally familiar drinks. Neuron. 2004 Oct 14; 44(2): 379-87.

Department of Neuroscience, Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030 USA.

Coca-Cola((R)) (Coke((R))) and Pepsi((R)) are nearly identical in chemical composition, yet humans routinely display strong subjective preferences for one or the other. This simple observation raises the important question of how cultural messages combine with content to shape our perceptions; even to the point of modifying behavioral preferences for a primary reward like a sugared drink. We delivered Coke and Pepsi to human subjects in behavioral taste tests and also in passive experiments carried out during functional magnetic resonance imaging (fMRI). Two conditions were examined: (1) anonymous delivery of Coke and Pepsi and (2) brand-cued delivery of Coke and Pepsi. For the anonymous task, we report a consistent neural response in the ventromedial prefrontal cortex that correlated with subjects' behavioral preferences for these beverages. In the brand-cued experiment, brand knowledge for one of the drinks had a dramatic influence on expressed behavioral preferences and on the measured brain responses.

PMID: 15473974 [PubMed - in process]


Today's New York Times Science section includes a look at this study and what so-called "neuromarketing" applications might develop.
If Your Brain Has a 'Buy Button,' What Pushes It?
By SANDRA BLAKESLEE
New York Times
19 October 2004

Knowing what brand you are buying can influence your preferences by commandeering brain circuits involved with memory, decision making and self-image, researchers have found.

When researchers monitored brain scans of 67 people who were given a blind taste test of Coca-Cola and Pepsi, each soft drink lit up the brain's reward system, and the participants were evenly split as to which drink they preferred. But when the same people were told what they were drinking, activity in a different set of brain regions linked to brand loyalty overrode their original preferences. Three out of four said that they preferred Coca-Cola.

The study, published in the Oct. 14 issue of the journal Neuron, is the first to explore how cultural messages penetrate the human brain and shape personal preferences.

Circulating in draft form over the last year, the study has been widely discussed by neuroscientists and advertisers, as well as people who worry about the power of commercials in determining consumer behavior.

At issue is whether marketers can exploit advances in brain science to make more effective commercials. Is there a "buy button" in the brain?
[ ... Read the full article ... ] (free registration required)

Monday, October 18, 2004

Imaging Alzheimer Disease - Part 2

Today's Yale Daily News includes an article about last week's announcement about the initiative to examine imaging technologies in the diagnosis of Alzheimer disease. The article is interesting to read of itself, but also because it touches briefly upon the concern of the neuropsychological community about the important role of neuropsychological assessment in the assessment of the cognitive changes that are diagnostically relevant:
Scientists seek earlier Alzheimer's diagnoses
BY ALBERTO MASLIAH
Contributing Reporter
Yale Daily News
Published Monday, October 18, 2004

[snip]

Currently, neuropsychological assessment is the most widely used instrument for neurocognitive ability and its deterioration. The introduction of imaging analysis used to differentiate which patients with mild cognitive impairment will progress to Alzheimer's and how far an Alzheimer's patient has progressed is relatively new.

Within the field of neuropsychology, there is controversy about whether this initiative's focus on imaging rather than currently used assessments will be effective.

"The way I see it, is that this is not meant to substitute [for] neuropsychological testing, but it should only be additive in terms of identifying who will progress to [Alzheimer's] and will only be beneficial to the patient," said Effie Mitsis, a neuropsychologist working with van Dyck.

[snip]

[ ... Read the full article ... ]

Saturday, October 16, 2004

Anosmia

Tomorrow's New York Times Sunday Magazine has a short piece written by someone who lost her sense of smell and her effort to try to find it once again:
Something's Off
By ROBIN MARANTZ HENIG
17 October 2004
The New York Times

[Snip]

Smell is the stepchild of the senses, the one that many think they could do without. But when I couldn't smell things, I couldn't fully inhabit the world, and my movements in it were somehow, almost imperceptibly, more clumsy. This month, when the Nobel Prize was awarded to two researchers for investigating the science of smell, it brought back my mixed feelings about my own sense of smell's protracted disappearance.

It vanished in 2002, a result of a bad fall. As my neurosurgeon explained, when my head hit the ground, my brain sloshed around, which smashed delicate nerve endings in my olfactory system. Maybe they'll repair themselves, she said (in what struck me as much too casual a tone), and maybe they won't. If I had to lose something, it might as well have been smell; at least nothing about my personality or my memory had changed, as can happen with head trauma. So it seemed almost churlish to feel, as the months went on, so devastated by this particular loss.

But I was heartbroken. My sense of smell was always something I took pleasure in. I could tell, by smelling him, if Jeff was troubled, excited or sad. I could fall in love with him all over again -- or with a passing stranger -- with one good whiff. And one of my favorite parts of mothering has been smelling my daughters, those deep sweet smells in the crooks of their necks and at the shaggy tops of their heads. Without scent, I felt as if I were walking around the city without my contact lenses, dealing with people while wearing earplugs, moving through something sticky and thick. The sharpness of things, their specificity, diminished.
[ ... Read the full article ...] (free registration required).

Friday, October 15, 2004

What's New In ...... Prosopagnosia?

Host G. [Prosopagnosia--incapacity to recognize faces] Lakartidningen. 2004 Aug 26;101(35):2661-2. Swedish. No abstract available. PMID: 15458222 [PubMed - indexed for MEDLINE]

Duchaine BC, Dingle K, Butterworth E, Nakayama K. Normal greeble learning in a severe case of developmental prosopagnosia. Neuron. 2004 Aug 19;43(4):469-73. PMID: 15312646 [PubMed - indexed for MEDLINE]

Hadjikhani N, Joseph RM, Snyder J, Chabris CF, Clark J, Steele S, McGrath L, Vangel M, Aharon I, Feczko E, Harris GJ, Tager-Flusberg H. Activation of the fusiform gyrus when individuals with autism spectrum disorder view faces. Neuroimage. 2004 Jul;22(3):1141-50. PMID: 15219586 [PubMed - indexed for MEDLINE]

Larner AJ. Lewis Carroll's Humpty Dumpty: an early report of prosopagnosia? J Neurol Neurosurg Psychiatry. 2004 Jul;75(7):1063. No abstract available. PMID: 15201376 [PubMed - indexed for MEDLINE]

Yamasaki T, Taniwaki T, Tobimatsu S, Arakawa K, Kuba H, Maeda Y, Kuwabara Y, Shida K, Ohyagi Y, Yamada T, Kira J.
Electrophysiological correlates of associative visual agnosia lesioned in the ventral pathway. J Neurol Sci. 2004 Jun 15;221(1-2):53-60. PMID: 15178214 [PubMed - indexed for MEDLINE]

Garcia Garcia R, Cacho Gutierrez LJ. [Prosopagnosia: is it a single or a multiple entity?] Rev Neurol. 2004 Apr 1-15;38(7):682-6. Review. Spanish. PMID: 15098192 [PubMed - indexed for MEDLINE]

Duchaine BC, Nakayama K. Developmental prosopagnosia and the Benton Facial Recognition Test. Neurology. 2004 Apr 13;62(7):1219-20. PMID: 15079032 [PubMed - indexed for MEDLINE]

Kilgour AR, de Gelder B, Lederman SJ. Haptic face recognition and prosopagnosia. Neuropsychologia. 2004;42(6):707-12. PMID: 15037050 [PubMed - indexed for MEDLINE]

Kobayashi K. [Progressive prosopagnosia associated with selective right temporal lobe atrophy] Nippon Rinsho. 2004 Jan;62 Suppl:171-4. Review. Japanese. No abstract available. PMID: 15011343 [PubMed - indexed for MEDLINE]

Snowden JS, Thompson JC, Neary D. Knowledge of famous faces and names in semantic dementia. Brain. 2004 Apr;127(Pt 4):860-72. Epub 2004 Feb 25. PMID: 14985259 [PubMed - indexed for MEDLINE]

Thursday, October 14, 2004

Imaging Alzheimer Disease

From a press release by the National Institute on Aging:
National Institute on Aging, Industry Launch Partnership, 60 Million Dollar Alzheimer’s Disease Neuroimaging Initiative
  
Wednesday, October 13, 2004, 10 a.m. ET

Contact:   Vicky Cahan
               Doug Dollemore
               (301) 496-1752

The National Institute on Aging (NIA) in conjunction with other Federal agencies, private companies and organizations today launched a $60 million, 5-year public-private partnership—the Alzheimer’s Disease Neuroimaging Initiative—to test whether serial magnetic resonance imaging (MRI), positron emission tomography (PET), other biological markers, and clinical and neuropsychological assessment can be combined to measure the progression of mild cognitive impairment (MCI) and early Alzheimer’s disease (AD).

The study could help researchers and clinicians develop new treatments and monitor their effectiveness as well as lessen the time and cost of clinical trials. The project is the most comprehensive effort to date to find neuroimaging and other biomarkers for the cognitive changes associated with MCI and AD.
[snip]

“This is an extraordinary pooling of talent and resources toward a common goal—delaying or preventing Alzheimer’s disease,” says Richard J. Hodes, M.D., Director of the NIA. “The initiative should become a landmark study in the development of neuroimaging and other biomarkers, helping us to find biological changes early so that we can identify the people at highest risk of the disease and test the effectiveness of new therapies more quickly and efficiently.”

The study will take place at approximately 50 sites across the U.S. and Canada.  In April 2005, investigators will begin recruiting about 800 adults, ages 55 to 90, to participate in the research—approximately 200 cognitively normal older individuals to be followed for 3 years, 400 people with MCI to be followed for 3 years, and 200 people with early AD to be followed for 2 years.

The study will compare neuroimaging, biological, and clinical information from these participants, seeking correlations among the data that will track the progression of memory loss from its earliest stages. Neuroimaging research has suggested that PET or MRI may serve as a more sensitive and consistent measure of disease progression than the neuropsychological and cognitive assessments now typically used in research and clinical practice. As MCI and AD progress, for example, areas of the brain involved with memory, such as the hippocampus (a part of the brain heavily involved in memory), shrink.

Using the high resolution images produced by MRI, researchers will evaluate the best ways of measuring this volume loss in the hippocampus and other brain structures. PET scans assess brain function by measuring the rate of metabolism of glucose, the brain’s fuel. PET scans of people with AD show that glucose in certain parts of the brain is metabolized at lower levels than in healthy people, and previous studies have shown that low glucose metabolism can be seen in some people even before noticeable symptoms of memory loss occur. The Initiative will seek to identify additional biological factors from blood, cerebrospinal fluid (CSF), and urine samples.
[ ... Read the full press release ... ]

Wednesday, October 13, 2004

MS Individuals Using Segways

The New York Times provides an interesting feature piece in its Circuits section tomorrow about the use of the Segway Human Transporter by individuals with various disabilities. It should also be noted that the creator of the Segway has developed a less-well-known wheelchair that can raise a person closer to eye level than a standard wheelchair and that can climb stairs.
Oft-Scorned Segway Finds Friends Among the Disabled
By RACHEL METZ
Published: October 14, 2004

WHIRRING quietly down the sidewalk on East 42nd Street and into a Starbucks one recent afternoon, Chandler Hovey drew looks and comments from passers-by.

What was most eye-catching was his means of transport: the Segway Human Transporter, a two-wheeled, gyroscopically balanced electric scooter. What was less evident, except to those close enough to spot the blue handicapped symbol on his scooter, was that he is disabled.

Mr. Hovey, 63, a money manager, has multiple sclerosis. For almost 18 months, his Segway has regularly transported him the roughly 30 blocks from his home to his office. When he is not using the Segway to dart around Manhattan, Mr. Hovey uses a cane, which he hangs on the scooter's handlebars, to help him maneuver around daily obstacles. But on the Segway, he appears as able-bodied as those he is passing by.

"Instead of being at fire hydrant height, you're at human being height," he said of many users. Several hundred people nationwide are using Segways to cope with disabilities like scoliosis and arthritis and even missing limbs, according to a group called Disability Rights Advocates for Technology, or Draft, which is promoting such use. Like Mr. Hovey, many have disabilities serious enough to require assistance with walking, but not a wheelchair.

The Segway, which has been generally available since early last year, is not approved (or marketed) for use as a medical device. And it has drawn opposition and even legislation in some cities over concern that its use on sidewalks endangers pedestrians. But that has not deterred disabled riders willing to pay $3,000 or more - a cost not usually covered by medical insurance.

Leonard Timm, an above-the-knees double amputee and a co-founder of Draft, said his group estimated the ranks of disabled Segway users nationwide at 400 to 600. Often, he said, they are using the Segway along with another device, like a cane, wheelchair or a sit-down power scooter.

Mr. Timm modified his Segway to incorporate a wooden seat he built that enables him to sit while riding. He is working on a new aluminum seat.

Disabled Segway riders cite health benefits like improved digestion and circulation. While their overall energy might not improve, some say they can now concentrate their efforts on things other than struggling to walk.
[ ... Read the full article ... ]

Rehabilitation Trends: Decreased Length of Stay and Mortality

Usually, the weekly online issue of the Journal of the American Medical Association includes the full text of one of its articles available on a free-access basis. Today's new issue has as its "free access" choice a report on trends in rehabilitation care: [access the article here]. A .pdf version is also available at the access page.

Here is the paper's abstract:
Kenneth J. Ottenbacher, PhD, OTR; Pam M. Smith, DNS, RN; Sandra B. Illig, MS, RN; Richard T. Linn, PhD; Glenn V. Ostir, PhD; Carl V. Granger, MD. Trends in Length of Stay, Living Setting, Functional Outcome, and Mortality Following Medical Rehabilitation. JAMA. 2004; 292: 1687-1695.

Context.  Changes in reimbursement have reduced length of stay (LOS) for patients receiving inpatient medical rehabilitation. The impact of decreased LOS on functional status, living setting, and mortality is not known.

Objective.  To examine changes in LOS, functional status, living setting, and mortality in patients completing inpatient rehabilitation.

Design.  Retrospective cohort study from 1994 through 2001 using information submitted to the Uniform Data System for Medical Rehabilitation.

Setting and Participants.  Data were analyzed from 744 inpatient medical rehabilitation hospitals and centers located in 48 US states. A total of 148 807 patient records from 5 impairment groups (stroke, brain dysfunction, spinal cord dysfunction, other neurologic conditions, and orthopedic conditions) were examined. Patients’ mean age was 67.8 (SD, 15.8) years; the sample was 59% female and 81% non-Hispanic white.

Main Outcome Measures.  Discharge setting, follow-up living setting, change in functional status, and mortality.

Results.  Median LOS decreased from 20 to 12 days (P less than .001) from 1994 to 2001. The proportional decrease in median LOS was greatest (42%) for patients with orthopedic conditions. Mean days to follow-up remained constant from 89 in 1994 to 90 in 2001. Functional status was clinically stable, while efficiency (functional status change divided by LOS) increased significantly (P less than .001). Rates of discharge to home and living at home at follow-up remained stable, ranging from 81% to 93%. However, mortality at 80- to 180-day follow-up increased from less than 1% in 1994 to 4.7% in 2001.

Conclusions.  Length of stay for inpatient rehabilitation decreased substantially from 1994 to 2001. Effectiveness as measured by change in functional status did not change clinically, and living setting did not change. Efficiency for functional outcomes improved but mortality at follow-up increased.

Medical Informatics: Implantable RF Microchips

The Washington Post reports on the approval by the FDA of the use of implantable radio-frequency microchips for medical information applications. As the article suggests, some neurological patients may fall within the targeted applications of this product.
FDA Approves Implantable Chip for Medical Records
By Diedtra Henderson
AP Science Writer
Wednesday, October 13, 2004; 2:05 PM

WASHINGTON (AP) -- The Food and Drug Administration on Wednesday approved an implantable computer chip that can pass a patient's medical details to doctors, speeding care.

VeriChips, radio frequency microchips the size of a grain of rice, have already been used to identify wayward pets and livestock. And nearly 200 people working in Mexico's attorney general's office have been implanted with chips to access secure areas containing sensitive documents.

Delray Beach, Fla.-based Applied Digital Solutions said it would give away $650 scanners to roughly 200 trauma centers around the nation to help speed its entry into the health care market.

A company spokesman would not say how much implanting chips would cost for humans, even though chips have been implanted in some, including Scott R. Silverman, the company's chief executive officer.

The company is targeting patients with diabetes, chronic cardiac conditions, Alzheimer's disease and those who undergo complex treatments like chemotherapy, said Dr. Richard Seelig, Applied Digital Solutions' vice president of medical applications.
[snip]
With the pinch of a syringe, the microchip is inserted under the skin in a procedure that takes less than 20 minutes and leaves no stitches.

Silently and invisibly, the dormant chip stores a code -- similar to the identifying UPC code on products sold in retail stores -- that releases patient-specific information when a scanner passes over the chip.

At the doctor's office those codes stamped onto chips, once scanned, would reveal such information as a patient's allergies and prior treatments.
[ ... Read the full article ... ] (free registration required)

Bilingualism and the Brain

A new study about the relation between the brain and bilinualism, as presented in a Reuters news report:
Learning 2nd Language Changes Brain Anatomy - Study
Wed 13 October, 2004 19:18
By Patricia Reaney
LONDON (Reuters) - Being bilingual produces changes in the anatomy of the brain, scientists said on Wednesday in finding that could explain why children are so much better than adults at mastering a second language.

They found that people who speak two languages have more gray matter in the language region of the brain. The earlier they learned the language, the larger the gray area.

"The gray matter in this region increases in bilinguals relative to monolinguals -- this is particularly true in early bilinguals who learned a second language early in life," said Andrea Mechelli, a neuroscientist at University College London.

"The degree is correlated with the proficiency achieved."

Learning another language after 35 years old also alters the brain but the change is not as pronounced as in early learners.

"It reinforces the idea that it is better to learn early rather than late because the brain is more capable of adjusting or accommodating new languages by changing structurally," Mechelli said.

"This ability of the brain decreases with time."

Mechelli and his team used structural brain imaging to compare the size of the gray matter in the brains of 25 monolinguals, 25 early bilinguals who learned a second language before the age of five and 33 late bilinguals.

All the volunteers in the study, which is described in the science journal Nature, were native English speakers of comparable age and education.

In the bilinguals, the gray matter in the left inferior parietal cortex was larger than in the monolinguals or the bilinguals who picked up the second language between the ages of 10-15.

"By looking at the size of the change (in the brain) I can tell whether someone is very proficient or not because the bigger the change the better the proficiency," said Mechelli.

Grey matter in the brain is made up of neurons, or brain cells. The scientists do not know whether the change in bilinguals means there is an increase in the size of the cells, the number of cells or the connections between them.

"The next step would be to understand the change better at a small-scale level," according to Mechelli.

He and his colleagues are planning further studies with people who have difficulty learning languages to see whether their brain behaves differently.

They also plan to study speakers of several languages to determine whether the increase in gray matter is proportional to the number of languages they have mastered.
[ ... Read the full report ... ]

Tuesday, October 12, 2004

Deep Brain Stimulation and Tourette's Syndrome

Over the past few months, there have been a number of stories in the media about the topic of deep brain stimulation and its possible applications in the near future. The following article comes from Canada’s Globe and Mail:
Surgery helps short-circuit Tourette's syndrome
By PAUL TAYLOR
From Tuesday's Globe and Mail

Jeff Matovic used to eat with a plastic spoon to prevent himself from accidentally gouging out one of his eyes.The 31-year-old has Tourette's syndrome, a neurological disorder characterized by involuntary muscle movements. Mr. Matovic, who developed symptoms at age 3, could not sit, walk or even sleep without his body exploding in an endless series of jerking motions and verbal outbursts. He has broken glasses in his bare hands and dented walls with his head because of sudden muscle contractions.

Things got so bad, Mr. Matovic sought out doctors who would implant electrodes in his brain to quiet his restless body, after hearing about another patient who had the treatment. The operation took place six months ago at the University Hospitals of Cleveland, and his body has been calm ever since.

"It's just amazing. It is truly phenomenal," Mr. Matovic said in a telephone interview from his home in a Cleveland suburb. Before the operation, he could barely talk on a phone because of an irrepressible urge to clear his throat, grunt and hiss -- not to mention the difficulty of holding the receiver.

Mr. Matovic underwent a treatment known as deep-brain stimulation, increasingly used to treat a wide range of brain disorders. Much like a heart pacemaker, the treatment provides a stream of electrical current to counteract a part of the brain that is misbehaving.

During surgery, electrodes are inserted into specific spots in the brain. They are then connected through wires under the skin (beneath the scalp, neck and upper chest) to a replaceable battery unit implanted beneath the collarbone.

Only a handful of people (none in Canada) has received the treatment for Tourette's. But deep-brain stimulation has been used for more than a decade to treat other movement disorders, such as Parkinson's disease, tremors and dystonia, which distorts posture. About 30,000 people around the world now have such brain implants.

As neurosurgeons refine their skills, medical experts speculate that deep-brain stimulation could be used to treat everything from drug addictions to depression. Studies are under way at various medical institutions to expand its use. The technique is proving effective partly because the brain itself operates like an electrical circuit. When even just a few brain cells are misfiring, they can cause widespread problems resulting in either a physical or mental disorder.

A little electrical current, applied in the right place, seems to restore harmony to the discordant symphony of the disordered brain, said Dr. Robert Maciunas, the neurosurgeon who operated on Mr. Matovic.
[ ... Read the full article ...]