Saturday, April 30, 2005

Ice Cream!

From The Guardian:

How ice cream tickles your brain
David Adam, science correspondent
Friday, April 29, 2005
The Guardian

Eating ice cream really does make you happy. Scientists have found that a spoonful of the cold stuff lights up the same pleasure centre in the brain as winning money or listening to your favourite music.

Neuroscientists at the Institute of Psychiatry in London scanned the brains of people eating vanilla ice cream. They found an immediate effect on parts of the brain known to activate when people enjoy themselves; these include the orbitofrontal cortex, the "processing" area at the front of the brain.

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

Thursday, April 28, 2005

What's New in ... Aphasia?

Here are references to some recent papers covering important topics in aphasia:

Otsuki M, Soma Y, Yoshimura N, Miyashita K, Nagatsuka K, Naritomi H. How to improve repetition ability in patients with Wernicke's aphasia: The effect of a disguised task. Journal of Neurology, Neurosurgery, and Psychiatry. 2005 May; 76(5): 733-735.

Grossman M, Moore P. A longitudinal study of sentence comprehension difficulty in primary progressive aphasia. Journal of Neurology, Neurosurgery, and Psychiatry. 2005 May; 76(5): 644-649.

Crosson B, Moore AB, Gopinath K, White KD, Wierenga CE, Gaiefsky ME, Fabrizio KS, Peck KK, Soltysik D, Milsted C, Briggs RW, Conway TW, Gonzalez Rothi LJ. Role of the right and left hemispheres in recovery of function during treatment of intention in aphasia. Journal of Cognitive Neuroscience 2005 Mar; 17(3): 392-406.

Bakheit A. Drug treatment of poststroke aphasia. Expert Rev Neurother. 2004 Mar; 4(2): 211-217.

Grossman M, Ash S. Primary progressive aphasia: A review. Neurocase. 2004 Feb; 10(1): 3-18.

Wednesday, April 27, 2005

Welcome to Ikaria

Abstract of the Day: Social Reasoning and Neuropsychology

Dana Samson, Ian A. Apperly, Umalini Kathirgamanathan and Glyn W. Humphreys. Seeing it my way: A case of a selective deficit in inhibiting self-perspective. Brain 2005 128(5):1102-1111; doi:10.1093/brain/awh464

University of Birmingham, Birmingham, UK

Correspondence to: Dana Samson,Behavioural Brain Sciences Centre, School of Psychology—Hills Building, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK

Little is known about the functional and neural architecture of social reasoning, one major obstacle being that we crucially lack the relevant tools to test potentially different social reasoning components. In the case of belief reasoning, previous studies have tried to separate the processes involved in belief reasoning per se from those involved in the processing of the high incidental demands such as the working memory demands of typical belief tasks. In this study, we developed new belief tasks in order to disentangle, for the first time, two perspective taking components involved in belief reasoning: (i) the ability to inhibit one's own perspective (self-perspective inhibition); and (ii) the ability to infer someone else's perspective as such (other-perspective taking). The two tasks had similar demands in other-perspective taking as they both required the participant to infer that a character has a false belief about an object's location. However, the tasks varied in the self-perspective inhibition demands. In the task with the lowest self-perspective inhibition demands, at the time the participant had to infer the character's false belief, he or she had no idea what the new object's location was. In contrast, in the task with the highest self-perspective inhibition demands, at the time the participant had to infer the character's false belief, he or she knew where the object was actually located (and this knowledge had thus to be inhibited). The two tasks were presented to a stroke patient, WBA, with right prefrontal and temporal damage. WBA performed well in the low-inhibition false-belief task but showed striking difficulty in the task placing high self-perspective inhibition demands, showing a selective deficit in inhibiting self-perspective. WBA also made egocentric errors in other social and visual perspective taking tasks, indicating a difficulty with belief attribution extending to the attribution of emotions, desires and visual experiences to other people. The case of WBA, together with the recent report of three patients impaired in belief reasoning even when self-perspective inhibition demands were reduced, provide the first neuropsychological evidence that the inhibition of one's own point of view and the ability to infer someone else's point of view rely on distinct neural and functional processes.

Monday, April 25, 2005

Functional Brain Mapping

The current issue of the journal Human Brain Mapping is a special-topic issue:

Special Issue: Meta-Analysis in Functional Brain Mapping . Issue Edited by Peter T. Fox, Angela R. Laird, and Jack L. Lancaster. Human Brain Mapping, Volume 25, Issue 1 (May 2005).

Here is the Table of Contents.

Nerve Growth Factor (NGF) and Alzheimer Disease

Technique Shows Promise Against Alzheimer's
By Rick Weiss
The Washington Post
Monday, April 25, 2005; Page A02

Injections of genetically altered cells into the brain appear to nourish ailing neurons and may slow the cognitive decline in patients with Alzheimer's disease, scientists reported yesterday in a preliminary study.

The experimental approach, pursued by researchers at the University of California at San Diego, aims to rejuvenate brain cells by providing a steady supply of a nerve-nurturing hormone secreted by the injected cells.

In studies involving a half-dozen Alzheimer's patients, most showed evidence of increased nerve growth and activity in the region of the brain most affected by the degenerative disease. Psychological test scores suggested the treatment also tempered the slow slide into dementia that is characteristic of Alzheimer's.

"If these effects are borne out in larger, controlled trials, this could be a significant advance over existing therapies for Alzheimer's disease," said study leader Mark Tuszynski, director of UCSD's Center for Neural Repair and a neurologist at the San Diego Veterans Affairs Medical Center.

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

fMRI and the Primary Visual Cortex

Improved Scanning Technique Uses Brain as Portal to Thought
By NICHOLAS WADE
The New York Times
Published: April 25, 2005

By peering not into the eyes but into the brain, an improved scanning technique has enabled scientists to figure out what people are looking at - even, in some cases, when they are not aware of what they have seen.

The advance, reported today, shows that the scanners may be better able than previously supposed to probe the border between conscious and unconscious thought and even, in certain circumstances, to read people's state of mind.

The scanning technique, known as functional magnetic resonance imaging, is a more powerful version of a technique widely used in hospitals. It can show which regions of the brain are actively performing some task, but until now has lacked the resolution to track specific groups of neurons, as the functional units of the brain are called.

The improvement lies not in the scanners themselves but in a new analytic technique developed by Dr. Frank Tong, a psychologist at Vanderbilt University. In today's issue of the journal Nature Neuroscience, he and a colleague, Dr. Yukiyasu Kamitani, report that they were able with the scanner to distinguish the orientation of a test pattern of lines being observed by their subjects.

The scanner was able to furnish the necessary data because it was looking into a region of the brain known as the primary visual cortex, where information from the eye is processed. One of the first relay stations from the retina, an area of the visual cortex called V1, holds columns of neurons that burst into activity when lines or edges are perceived, with each column responding to a specific angle of orientation.

Dr. Tong set the scanner to monitor the orientation columns in V1. Though the columns of neurons are too small for the scanner to see directly, he found a way to infer statistically which columns were active and hence which orientation the V1 area was responding to.

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

Sunday, April 24, 2005

Screening of Cognitive Functioning for the Elderly

Some Seniors Turning to Brain Screening
Sat Apr 23, 8:11 PM ET
Health - AP
By JAMIE STENGLE, Associated Press Writer

DALLAS - Bill Crist was angry and upset when his doctor diagnosed him with dementia. But the 64-year-old retired pharmacist felt a little better after going to the Center for BrainHealth for an evaluation, which showed his language skills and memory were still quite strong.

Crist suffers from a neurodegenerative disorder that is associated with Alzheimer's and Parkinson's disease. He said the follow-up test helped show him which brain functions "look normal."

Such exams are becoming increasingly popular as aging Americans try to differentiate between normal aging problems and the effects of neurological conditions.

[ ... Read the full article at Yahoo! ... ]

Business World: Seattle's Ikaria

The Hutch to set up biotech firm
Mice-hibernation scientist to help form Ikaria Inc.
By BRAD WONG
Seattle Post-Intelligencer
Saturday, April 23, 2005

Seattle cell biologist Mark Roth and the Fred Hutchinson Cancer Research Center are teaming up to form Ikaria Inc., a new biotechnology company that seeks to use Roth's discovery of inducing hibernation in mice to help humans with organ transplants, trauma and cancer care.

Word of the new company follows yesterday's publication of Roth's groundbreaking study in the edition of Science.

The company does not yet have a chief executive, said Spencer Lemons, a Hutch technology transfer executive who is overseeing the discovery that was done at the Seattle research institute.

Roth, a Hutch researcher and the study's lead investigator, discovered that oxygen deprivation in mice led to a reversible state of hibernation. For doctors who need to stop bodily functions, this discovery gives hope that the same process could be done in humans, especially for cancer and trauma care.

Roth yesterday declined to comment on the new company.

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

Here is the abstract of the research article in this week's issue of Science:

Blackstone E, Morrison M, Roth MB. H2S Induces a Suspended Animation-Like State in Mice. Science. 2005 Apr 22; 308(5721): 518.

Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98195, USA.

Mammals normally maintain their core body temperature (CBT) despite changes in environmental temperature. Exceptions to this norm include suspended animation-like states such as hibernation, torpor, and estivation. These states are all characterized by marked decreases in metabolic rate, followed by a loss of homeothermic control in which the animal's CBT approaches that of the environment. We report that hydrogen sulfide can induce a suspended animation-like state in a nonhibernating species, the house mouse (Mus musculus). This state is readily reversible and does not appear to harm the animal. This suggests the possibility of inducing suspended animation-like states for medical applications.

PMID: 15845845 [PubMed - in process]

Saturday, April 23, 2005

Must "C" TV: Cognitively Demanding Television

It has always struck me as odd that people criticize television watching as mindless entertainment. Hardly mindless. Attentional and memory demands, abstraction, requirements imposed by presentation of diverse vantage points, fast pacing, and so on, all point to fairly active neurocognition. Indeed, in some of my rehabilitation patients, I often assign choosing and watching a favorite TV show as an adjunctive and supportive "at home" task.

Steven Johnson provides an interesting perspective in tomorrow's New York Times Sunday Magazine, in an essay adapted from his new book, Everything Bad Is Good for You: How Today's Popular Culture Is Actually Making Us Smarter.
Watching TV Makes You Smarter
By STEVEN JOHNSON
The New York Times
Published: April 24, 2005

[snip]

For decades, we've worked under the assumption that mass culture follows a path declining steadily toward lowest-common-denominator standards, presumably because the ''masses'' want dumb, simple pleasures and big media companies try to give the masses what they want. But as that ''24'' episode suggests, the exact opposite is happening: the culture is getting more cognitively demanding, not less. To make sense of an episode of ''24,'' you have to integrate far more information than you would have a few decades ago watching a comparable show. Beneath the violence and the ethnic stereotypes, another trend appears: to keep up with entertainment like ''24,'' you have to pay attention, make inferences, track shifting social relationships. This is what I call the Sleeper Curve: the most debased forms of mass diversion -- video games and violent television dramas and juvenile sitcoms -- turn out to be nutritional after all.

I believe that the Sleeper Curve is the single most important new force altering the mental development of young people today, and I believe it is largely a force for good: enhancing our cognitive faculties, not dumbing them down.

[snip]
[ ... Read the full article ... ] (free registration required)
~
Addendum - Information about the book by its author can be found at his blog:
click here

Friday, April 22, 2005

In The Weeklies

This week's 21 April 2005 issue of The New England Journal of Medicine includes a case vignette examining rehabilitation after stroke:

Bruce H. Dobkin. Rehabilitation after stroke. The New England Journal of Medicine 2005; 352: 1677-1684.

Thursday, April 21, 2005

Narrative: Post-Traumatic-Brain-Injury Recovery

This narrative by a writer for The Miami Herald includes a good description of the resolution of her post-traumatic amnesia (PTA) (also called post-traumatic confusional state) in the recovery from the head injury she sustained.

Recovering life, self after coma
BY ELISA TURNER
The Miami Herald
18 April 2005
[ ... Read the full article ... ]

[snip]

Elisa Turner, The Herald's art critic, was in a severe car accident in August. The accident left her in a coma. Here is her story on finding her way back.

It was the water's spray that nudged me back, its warmth on my skin tugging me from the stupor that had robbed me of sensation, of my self, of everything. Though still only half awake, I realized I was sitting on a chair in a shower and that my close friend Iliana Garcia was washing my hair.

But the bathroom tile, a drab beige I never would have chosen, did not make sense. Where was I? Why was Iliana washing my hair? I will never forget the weirdness of waking up this way. Then my dim awareness melted away, and I got very sleepy again.

[snip]

Wednesday, April 20, 2005

Anti-Epileptic Medications: FDA Request

From today's Boston Globe

FDA requests anticonvulsants be reexamined

By Liz Kowalczyk
The Boston Globe
April 20, 2005

The Food and Drug Administration has asked the makers of epilepsy drugs, which are the fifth best-selling group of medications and are taken by millions of Americans, to reexamine their data to determine if the drugs increase patients' risk of suicide.

The agency has requested an analysis similar to the one it commissioned to evaluate whether antidepressants pose a similar risk to children and teenagers. That sweeping reexamination of clinical trial data found that antidepressants can increase suicidal thoughts and behavior in young people, and last year the FDA required manufacturers to include a stronger, more prominent warning, known as a ''black box," on the drugs' labels.

The agency, which has been the target of growing criticism from members of Congress over how it monitors drug safety, is under pressure to more carefully scrutinize anticonvulsants, particularly Neurontin, which is made by Pfizer Inc. and is the market leader.

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

Tuesday, April 19, 2005

Medical History: Clinical Trials and Retrolental Fibroplasia

Today's Washington Post has a full feature story from the annals of medical history:

Establishing Proof
Some Fifty Years Ago a Baby-Blinding Epidemic Confounded Experts -- Until a Pioneering Study Conclusively Tied Cause and Effect, and Enshrined Clinical Trials in Medical Practice
By David Brown
The Washington Post
Tuesday, April 19, 2005; Page HE01

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

[snip]

The story of oxygen and blindness is a distant mirror of these therapeutic surprises. But it is much more as well.

Of all the elements on the periodic table, oxygen is the one that seems most to symbolize life and health itself. Could extra oxygen be dangerous to tiny babies struggling to survive? It seemed inconceivable!

But it was true. Two doctors proved it more than a half-century ago in a clinical experiment run in the wards of a hospital in Washington. The medical world didn't believe them, at least not enough to change routine practice. So a second, bigger experiment was conducted at more than a dozen American hospitals.

Fifty years ago this summer, the preliminary results of that trial were published. They changed medical history. Almost overnight, physicians stopped automatically giving supplemental oxygen to preemies, ending the epidemic of retrolental fibroplasia (RLF), as the disease was called then. (It is now known as retinopathy of prematurity.)

But the study's results did something else equally important and historic. They convinced many American physicians of the usefulness of randomized controlled trials, which had been "invented" less than 10 years earlier in Britain. Not least, the study taught doctors they couldn't assume that what seemed like a good idea -- extra oxygen -- would necessarily lead to a good outcome.

"Doctors have to approach their patients, and what they think they know, with a certain amount of humility," said Steven Goodman, a physician at Johns Hopkins University's Bloomberg School of Public Health and editor of the journal Clinical Trials. "This is one of the trials that taught us humility."

[snip]

Event: Tokyo, 29 April - 01 May 2005

An International Symposium on "Epileptic Syndromes in Infancy and Early Childhood—Evidence-based Taxonomy and Its Implications in the ILAE Classification," will be held at Tokyo Women’s Medical University Campus, Tokyo, Japan. The meeting will take place from the 29th of April through the 1st of May, 2005.

For further information, visit the following website: Infantile Seizure Society.

Thursday, April 14, 2005

Hyponatremia

Study Cautions Runners to Limit Their Water Intake
The New York Times
By GINA KOLATA
Published: April 14, 2005

After years of telling athletes to drink as much liquid as possible to avoid dehydration, some doctors are now saying that drinking too much during intense exercise poses a far greater health risk.

An increasing number of athletes - marathon runners, triathletes and even hikers in the Grand Canyon - are severely diluting their blood by drinking too much water or too many sports drinks, with some falling gravely ill and even dying, the doctors say.

New research on runners in the Boston Marathon, published today in The New England Journal of Medicine, confirms the problem and shows how serious it is.

The research involved 488 runners in the 2002 marathon. The runners gave blood samples before and after the race. While most were fine, 13 percent of them - or 62 - drank so much that they had hyponatremia, or abnormally low blood sodium levels. Three had levels so low that they were in danger of dying.

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

Wednesday, April 13, 2005

Donepezil, Vitamin E, and Mild Cognitive Impairment in Aging

The New England Journal of Medicine has made available on its website prepublication versions of the results of a large study relevant to aging, neuropsychological changes in aging, and the onset of dementia. It has also made available in the same format an editorial on this research study. The full-text versions of both articles can be found at: Original Article and at Editorial.

The editorial, by Blacker, concludes by bringing emphasis to three primary findings in the study:

[1] Symptoms of memory loss in older persons need to be taken with seriousness, as they may herald the onset of Alzheimer disease.
[2] Donepezil may have some benefit, but this benefit is "quite limited and apparently transient."
[3] Vitamin E has no impact.


As a neuropsychologist, I can say that the clearest way to examine symptoms of memory problems is through a thorough neuropsychology examination.

Vitamin E and Donepezil for the Treatment of Mild Cognitive Impairment. Ronald C. Petersen, Ph.D., M.D., Ronald G. Thomas, Ph.D., Michael Grundman, M.D., M.P.H., David Bennett, M.D., Rachelle Doody, M.D., Ph.D., Steven Ferris, Ph.D., Douglas Galasko, M.D., Shelia Jin, M.D., M.P.H., Jeffrey Kaye, M.D., Allan Levey, M.D., Ph.D., Eric Pfeiffer, M.D., Mary Sano, Ph.D., Christopher H. van Dyck, M.D., Leon J. Thal, M.D., for the Alzheimer's Disease Cooperative Study Group. Published at www.nejm.org April 13, 2005 (10.1056/NEJMoa050151)

ABSTRACT

Background. Mild cognitive impairment is a transitional state between the cognitive changes of normal aging and very early Alzheimer's disease.

Methods. In a double-blind study, we evaluated subjects with the amnestic subtype of mild cognitive impairment. Subjects were randomly assigned to receive 2000 IU of vitamin E daily, 10 mg of donepezil daily, or placebo for three years. The primary outcome was clinically possible or probable Alzheimer's disease; secondary outcomes were cognition and function.

Results. A total of 769 subjects were enrolled, and possible or probable Alzheimer's disease developed in 212. The overall rate of progression from mild cognitive impairment to Alzheimer's disease was 16 percent per year. As compared with the placebo group, there were no significant differences in the probability of progression to Alzheimer's disease in the vitamin E group (hazard ratio, 1.02; 95 percent confidence interval, 0.74 to 1.41; P=0.91) or the donepezil group (hazard ratio, 0.80; 95 percent confidence interval, 0.57 to 1.13; P=0.42) during the three years of treatment. Prespecified analyses of the treatment effects at 6-month intervals showed that as compared with the placebo group, the donepezil group had a reduced likelihood of progression to Alzheimer's disease during the first 12 months of the study (P=0.04), a finding supported by the secondary outcome measures. Among carriers of one or more apolipoprotein E 4 alleles, the benefit of donepezil was evident throughout the three-year follow-up. There were no significant differences in the rate of progression to Alzheimer's disease between the vitamin E and placebo groups at any point, either among all patients or among apolipoprotein E 4 carriers.

Conclusions. Vitamin E had no benefit in patients with mild cognitive impairment. Although after three years, the rate of progression to Alzheimer's disease was not lower among patients treated with donepezil than among those given placebo, donepezil therapy was associated with a lower rate of progression to Alzheimer's disease during the first 12 months of treatment.

Notice: To coincide with a presentation at the annual meeting of the American Academy of Neurology, this article was published at www.nejm.org on April 13, 2005. It will appear in the June 9 issue of the Journal.

Editorial:

Deborah Blacker, M.D., Sc.D. Mild Cognitive Impairment -- No Benefit from Vitamin E, Little from Donepezil. Published at www.nejm.org April 13, 2005 (10.1056/NEJMe058086).

Event: AAN in Miami Beach, 09-16 April 2005

The 57th Annual Meeting of the American Academy of Neurology (AAN) is being held at this time in Miami Beach, FL. Information about the conference can be found at the conference webpage.

Tuesday, April 12, 2005

Modafinil for Fatigue in Multiple Sclerosis

B. Stankoff, MD, PhD, E. Waubant, MD, PhD, C. Confavreux, MD, G. Edan, MD, M. Debouverie, MD, L. Rumbach, MD, T. Moreau, MD, PhD, J. Pelletier, MD, PhD, C. Lubetzki, MD, PhD, M. Clanet, MD, PhD and French Modafinil Study Group.
Modafinil for fatigue in MS: A randomized placebo-controlled double-blind study. Neurology 2005; 64: 1139-1143.

From the Fédération de Neurologie (Drs. Stankoff and Lubetzki), Centre d’Investigation Clinique (Drs. Stankoff and Waubant), Hôpital de la Salpêtrière, AP-HP, Paris, France; Services de Neurologie, CHU de Lyon (Dr. Confavreux), Rennes (Dr. Edan), Nancy (Dr. Debouverie), Besançon (Dr. Rumbach), Dijon (Dr. Moreau), and Marseille (Dr. Pelletier); Fédération de Neurologie (Dr. Clanet), CHU de Toulouse, France; and UCSF MS Center (Dr. Waubant), San Francisco, CA.

Objective: To assess whether modafinil, a wakefulness-promoting agent, is useful for fatigue in patients with multiple sclerosis (MS).

Methods: Patients with MS with stable disability, and a baseline score of 45 or more on the Modified Fatigue Impact Scale (MFIS), were eligible for the 5-week randomized, double-blind, placebo-controlled, parallel group study. The initial daily dose of modafinil was 200 mg for 1 week. Depending on tolerance, the dose was increased by 100 mg every week up to 400 mg/day and remained unchanged between day 21 and day 35. The primary outcome variable was the change of MFIS score at day 35.

Results: A total of 115 patients with MS were enrolled in the study and in the intention to treat analysis. The mean MFIS score at baseline was 63 ± 9 in the placebo group and 63 ± 10 in the modafinil group. MFIS scores improved between day 0 and day 35 in both placebo-treated and modafinil-treated groups, but no significant difference was detected between the two groups. There was no major safety concern.

Conclusions: There was no improvement of fatigue in patients with multiple sclerosis treated with modafinil vs placebo according to the Modified Fatigue Impact Scale.

Monday, April 11, 2005

Dendritic Spines and Long-Term Plasticity

Neuroscientific and basic neuropsychological research about changes in the brain that occur as a result of learning are topical areas of novel technologies and rapid developments. The new April 2005 issue of Nature Reviews Neuroscience includes a free download of the full text of a review article about these developments:

Segal, M. (2005). Dendritic spines and long-term plasticity. Nature Reviews Neuroscience, 6, 277-284. [doi:10.1038/nrn1649]

Department of Neurobiology, The Weizmann Institute, Rehovot, 76100 Israel.

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

Abstract

A recent flurry of time-lapse imaging studies of live neurons have tried to address the century-old question: what morphological changes in dendritic spines can be related to long-term memory? Changes that have been proposed to relate to memory include the formation of new spines, the enlargement of spine heads and the pruning of spines. These observations also relate to a more general question of how stable dendritic spines are. The objective of this review is to critically assess the new data and to propose much needed criteria that relate spines to memory, thereby allowing progress in understanding the morphological basis of memory.

Sunday, April 10, 2005

Blink: Media, Media

Malcolm Gladwell was featured on this morning's CBS show Sunday Morning and was interviewed on the CBC's weekly book show Hot Type (airing at various times depending upon location).

Friday, April 08, 2005

Event: New York, 09-12 April 2005

The Cognitive Neuroscience Society (CNS) opens its annual meeting tomorrow in New York City. Information can be found at the conference homepage.

Thursday, April 07, 2005

Business World: Cyberonics and Neurostimulators

The Houston Press, which is an alternative news weekly in Houston, has a feature article this week about Cyberonics and its epilepsy device and its exploration of applications in mood disorders:

Exposed Nerve
Cyberonics has implanted its pacemaker in thousands of epileptics. It wants to expand to the depression market. Still needed: an accounting of those who died or were injured after receiving its implant.
BY CRAIG MALISOW
The Houston Press
7-13 April 2005

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

Monday, April 04, 2005

Unconsciousness

From tomorrow's Times, a feature article about the different states of unconsciousness and the different etiologies that may cause them to occur:

Inside the Injured Brain, Many Kinds of Awareness
The New York Times
By BENEDICT CAREY
Published: April 5, 2005

Read the article (free registration required)

~

Here is the abstract of one of the research studies reported in the article:

Whyte J, Katz D, Long D, DiPasquale MC, Polansky M, Kalmar K, Giacino J, Childs N, Mercer W, Novak P, Maurer P, Eifert B. Predictors of outcome in prolonged posttraumatic disorders of consciousness and assessment of medication effects: A multicenter study. Archives of Physical Medicine and Rehabilitation. 2005 Mar; 86(3): 453-462.

Moss Rehabilitation Research Institute/Albert Einstein Healthcare Network, Philadelphia, PA, USA.

OBJECTIVES: To develop predictive models of recovery from the vegetative state (VS) and minimally conscious state (MCS) after traumatic brain injury (TBI) and to gather preliminary evidence on the impact of various psychotropic medications on the recovery process to support future randomized controlled trials. Design Longitudinal observational cohort design, in which demographic information, injury and acute care history, neuroimaging data, and an initial Disability Rating Scale (DRS) score were collected at the time of study enrollment. Weekly follow-up data, consisting of DRS score, current psychoactive medications, and medical complications, were gathered until discharge from inpatient rehabilitation. SETTING: Seven acute inpatient rehabilitation facilities in the United States and Europe with specialized programs for treating patients in the VS and MCS. PARTICIPANTS: People with TBI (N=124) who were in the VS or MCS 4 to 16 weeks after injury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: DRS score at 16 weeks after injury and time until commands were first followed (among those participants demonstrating no command following at study enrollment). Results DRS score at enrollment, time between injury and enrollment, and rate of DRS change during the first 2 weeks of poststudy observation were all highly predictive of both outcomes. No variables related to injury characteristics or lesions on neuroimaging were significant predictors. Of the psychoactive medications, amantadine hydrochloride was associated with greater recovery and dantrolene sodium was associated with less recovery, in terms of the DRS score at 16 weeks but not the time until commands were followed. More detailed analysis of the timing of functional improvement, with respect to the initiation of amantadine provided suggestive, but not definitive, evidence of the drug's causal role. CONCLUSIONS: These findings show the feasibility of improving outcome prediction from the VS and MCS using readily available clinical variables and provide suggestive evidence for the effects of amantadine and dantrolene, but these results require confirmation through randomized controlled trials.

PMID: 15759228 [PubMed - in process]

Software for a Game Brain

From sfgate.com:

Calisthenics for aging brains
S.F. firm develops software to improve mental agility

The San Francisco Chronicle
Monday, April 4, 2005
Carolyn Said, Chronicle Staff Writer

[snip]

... Posit Science says its brain-training program takes a more rigorous approach, backed by scientific research.

Posit co-founder and Chief Scientific Officer Michael Merzenich, a professor of neuroscience at UCSF, has spent more than 30 years researching brain plasticity.

"The brain is just as deserving of a workout as the body," he said in a presentation to a national conference on aging last month. "The brain needs progressively challenging learning that is intensive, effortful and repetitive. "

That premise underlies Posit's approach to cognitive calisthenics.

Posit scientists created exercises to stimulate specific brain functions. Then its video game designers turned them into computer games, complete with a couple of animated coaches to give tips and rewards like amusing pictures when players complete tasks.

The company says one key to brain rejuvenation is that the exercises become more difficult as players progress so they're always working at a threshold of intensity.

"As we age, things get 'noisier.' Information from our senses is less reliable and processed less well," said Posit co-founder and Chief Executive Officer Jeff Zimman. "The systems in the brain get sluggish. We're trying to improve the ability to accurately process signals (such as incoming verbal information), increase speed and stimulate the machinery to produce key brain chemicals."

Posit started just 18 months ago but already has 53 issued patents, almost all for Merzenich's inventions. (He's a member of the National Academy of Sciences whose credits also include being on the team that invented the cochlear implant in the late 1980s.) Posit licensed many of them from Scientific Learning, an Oakland company Merzenich founded in 1996 that makes software to teach language and reading skills to K-12 students.

Posit has raised $7.2 million in venture capital and is seeking more funding.

The software isn't quite ready for prime time. Posit hopes to release the first module, which is focused on hearing, by the end of the year. Future modules will address eyesight, problem solving and multitasking, motor control, and balance and mobility.

Pricing will vary from less than $50 to $1,000 depending on intensity levels and other factors. Zimman said he envisions senior residences and other facilities buying site licenses to set up cognitive fitness centers, or "brain gyms."

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

Saturday, April 02, 2005

Drs. Brenda Milner and Endel Tulving Honored

From The Globe and Mail:
Award recognizes Canadian memory research
Cognitive neuroscientists Brenda Milner of McGill University in Montreal and Endel Tulving of the University of Toronto are recipients of the 2005 Gairdner Awards
By JORDAN PRESS
Saturday, April 2, 2005 Updated at 6:09 AM EST
From Saturday's Globe and Mail

Two Canadian psychologists have achieved additional international recognition for their groundbreaking work on how people remember and recall memories.Cognitive neuroscientists Brenda Milner of McGill University in Montreal and Endel Tulving of the University of Toronto are recipients of the 2005 Gairdner Awards. Of the 273 Gairdner winners, 64 have subsequently won the Nobel Prize.

"It is very surprising to me that I was granted this award," Dr. Tulving said yesterday. "The Gairdners are medical awards, and I'm not a medical person . . . I'm a cognitive psychologist."

The 77-year-old researcher has been studying memory since the 1970s. While other researchers focused on where memories are stored in the brain, Dr. Tulving became one of the first to look at how memories are retrieved.

The Harvard graduate has taught at Yale and U of T and is chairman of cognitive neuroscience at the Rotman Research Institute.

The other Canadian winner is still teaching at the age of 86. Prof. Milner lectures at McGill and conducts research at the Montreal Neurological Institute.

Her work has been recognized worldwide and she is credited with making Canada a top spot for memory research. Forty years ago, Prof. Milner's work focused on the way each side of the brain operates, which was instrumental in identifying which areas are essential to memory.

Prof. Milner is best known for her work with a patient known as H.M.
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