Friday, August 26, 2005

Orexin and the Lateral Hypothalamus

From the National Institutes of Health (NIH):
Thursday, August 25, 2005

Researchers Identify a Brain Chemical That Plays a Key Role in Food and Drug-Seeking Behavior

New research performed in rats suggests that orexin, a brain chemical involved in feeding behavior, arousal, and sleep, also plays a role in reward function and drug-seeking behavior.

Dr. Glenda Harris and her colleagues at the University of Pennsylvania showed that the activation of orexin-secreting brain cells in the hypothalamus, a brain region that controls many vital functions such as eating, body temperature, fat metabolism, etc. is strongly correlated with food- and drug-seeking behaviors. Past anatomical studies have shown that these cells in the lateral hypothalamus also project to adjacent reward-associated areas of the brain.

This study suggests that orexin may be a factor in modulating reward-seeking characteristic of substance abuse. The findings help to better identify neural pathways involved in drug abuse, craving and relapse, which may ultimately help scientists find more effective therapies.

This study is published online August 14, 2005 in the journal Nature.

“The brain cells that secrete this substance, orexin, are in an area of the brain called the lateral hypothalamus,” says Dr. Nora D. Volkow, director of the National Institute on Drug Abuse (NIDA), National Institutes of Health, which supported the study. “This brain region has been implicated in reward function for many years, but no one was sure which brain chemicals, or neurotransmitters, were involved. For the first time, we now know exactly which substances are involved, which is a significant step forward in developing treatments.”


“We found that the more animals seek out cues associated with food or drug reward, the more activated these neurons become,” says Dr. Harris. In rats that had their drug-seeking behavior extinguished, the preference for drug-associated cues was reinstated by chemically activating these cells and orexin production. These data suggest that this brain system may be involved in the development of drug craving that can perpetuate both addiction and relapse.

“This neural system may be activated by environmental cues that cause addicts to relapse back to drug-taking behavior even after successfully going through rehabilitation and achieving abstinence,” says Dr. Volkow.
[ ... Read the full press release ... ]
Anthony H. Risser | |

Tuesday, August 23, 2005

Abstract of the Day: Neuropsychology of 'What' and 'Where' Streams in Visual Working Memory

Finke K, Bublak P, & Zihl J. Visual spatial and visual pattern working memory: Neuropsychological evidence for a differential role of left and right dorsal visual brain. Neuropsychologia. 2005 Aug 16; [Epub ahead of print].

Department of Psychology, Neuropsychology, Ludwig-Maximilian University of Munich, Leopoldstrasse 13, D-80802 Munchen, Germany; Max Planck Institute of Psychiatry, Munich, Germany.

According to neurophysiological, neuroimaging, and behavioural evidence, visual working memory (WM) can be separated into a "what" and a "where" component, reflecting the duality of visual processing. Whereas a wealth of empirical data suggests a right-sided fronto-parietal network critical for the maintenance of spatial information, the cortical structures underlying maintenance of object information have remained controversial. Although visual object processing depends on ventral, inferior temporal areas, recent neuroimaging results suggest that maintenance of visual object information involves a left-sided or bilateral fronto-parietal network. The aim of the present study is to further clarify the role of the left and right parietal lobes for pattern and spatial visual WM. Seven patients with left-sided, seven with right-sided parietal brain injury, and two age-matched healthy control groups performed a delayed-matching-to-sample task using either pattern (shape) or spatial (location) information or both. In addition, eight patients with left-sided injury sparing parietal areas were tested to further examine the specific role of the left parietal cortex in pattern WM. Left parietal injury resulted in pattern WM impairment, only, while right parietal injury was associated with pattern and spatial WM deficits. Non-parietal injury was not associated with comparable deficits. These results suggest that visual spatial WM depends critically on right parietal areas; in contrast, pattern WM depends on both, left and right parietal areas.

PMID: 16111725 [PubMed - as supplied by publisher]
Anthony H. Risser | |

Monday, August 22, 2005

Better Than Enron: The Enteric Nervous System

From tomorrow's New York Times:
The Other Brain Also Deals With Many Woes
The New York Times
Published: August 23, 2005

Two brains are better than one. At least that is the rationale for the close - sometimes too close - relationship between the human body's two brains, the one at the top of the spinal cord and the hidden but powerful brain in the gut known as the enteric nervous system.

[ .. Read the full story ...]

That title for my post? Ask why. The brains at Enron initially decided to call their company "Enteron," but shortened the name once they realized its intestinal nature. Pity they went through the trouble of changing the name - given what Enron eventually produced ... (grin)
Anthony H. Risser | |

Abstract of the Day: The Eye of the Beholder

Hannah Faye Chua, Julie E. Boland, & Richard E. Nisbett. Cultural variation in eye movements during scene perception. Proceedings of the National Academy of Sciences; 2005. ePub ahead of publication. 10.1073/pnas.0506162102

Department of Psychology, University of Michigan, 530 Church Street, Ann Arbor, MI 48109-1043

In the past decade, cultural differences in perceptual judgment and memory have been observed: Westerners attend more to focal objects, whereas East Asians attend more to contextual information. However, the underlying mechanisms for the apparent differences in cognitive processing styles have not been known. In the present study, we examined the possibility that the cultural differences arise from culturally different viewing patterns when confronted with a naturalistic scene. We measured the eye movements of American and Chinese participants while they viewed photographs with a focal object on a complex background. In fact, the Americans fixated more on focal objects than did the Chinese, and the Americans tended to look at the focal object more quickly. In addition, the Chinese made more saccades to the background than did the Americans. Thus, it appears that differences in judgment and memory may have their origins in differences in what is actually attended as people view a scene.
Anthony H. Risser | |

Sunday, August 21, 2005

Abstract of the Day: Hashimoto's Encephalopathy

Gayatri, N.A. & Whitehouse, W.P. Pilot survey of Hashimoto's encephalopathy in children. Developmental Medicine and Child Neurology; 2005 Aug; 47(8): 556-8.

Department of Paediatric Neurology, Queen's Medical Centre, Nottingham, UK.

Hashimoto's encephalopathy (HE) is a steroid responsive, relapsing encephalopathy associated with thyroid autoantibodies. Paediatric literature mainly consists of case reports of the disease. A questionnaire survey of 68 consultant paediatric neurologists was undertaken through the British Paediatric Neurology Association in 2002 to gather preliminary data about this condition. The response rate was 68% and a total of ten patients were identified: nine from the UK and one from Ireland. Complete clinical details were available on eight patients (seven females and one male). Age at presentation ranged from 10 to 15 years (mean 12y 7mo, SD 1y 1mo). Presenting features included seizures (n=7/8), encephalopathy (n=7/8), cognitive decline (n=4/8), behavioural problems (n=3/8), psychosis (n=2/8), myoclonus (n=1/8), and tremors (n=1/8). All had thyroid autoantibodies and four were also hypothyroid at diagnosis. One patient became hypothyroid during follow-up. Electroencephalograms (EEGs) showed high amplitude slow background rhythms in all patients, and one patient also had focal spikes. Cognitive deficits were identified in four patients and persisted in one over 2 years of follow-up. Six patients improved with steroids and two improved spontaneously. Two had relapsing courses during follow-up afer diagnosis (range 12-48 months). HE may be currently under-recognized in children and increased awareness can result in prompt diagnosis and treatment. Steroid therapy appears to be beneficial. Neuropsychological assessment is required in all cases and may guide steroid therapy. Long-term prognosis for cognition remains guarded at this time.

PMID: 16108457 [PubMed - in process]
Anthony H. Risser | |

In The Weeklies: Cerebrovascular Events (CVAs)

The 20 August 2005 issue of the British Medical Journal includes the following papers, in full-text format:

Charles D A Wolfe, Nigel C Smeeton, Catherine Coshall, Kate Tilling, & Anthony G Rudd. Survival differences after stroke in a multiethnic population: Follow-up study with the south London stroke register. British Medical Journal; 2005:431. [doi:10.1136/bmj.38510.458218.8F]

Mushtaq Wani, Emma Nga, & Ranjini Navaratnasingham. Evidence based case report: Should a patient with primary intracerebral haemorrhage receive antiplatelet or anticoagulant therapy? British Medical Journal; 2005: 439-442. [doi:10.1136/bmj.331.7514.439]
Anthony H. Risser | |

Saturday, August 20, 2005

The Game Brain & The Examined Life: Mental Workouts, Memoir Groups

ABC's World News Tonight ran two segments this evening about human memory over the course of aging, for lifestyle and disease-driven issues: Memory Bank and Saving Memories

The first, by reporter Bob Jamieson, included interviews with Drs. Gary Small of UCLA and Yaakov Stern of Columbia. Mental exercises, etc.

The second, by reporter Brain Rooney, examined the growth of memoir groups, where individuals prepare stories from their lives and then share them by reading them aloud within their group. The report also made note of the growing industry of ghostwriters (and, in some cases, video producers) who make their services available to develop personal memories and histories into a more-polished product.
Anthony H. Risser | |

Thursday, August 18, 2005

Caring for an Elderly Population: An Interview with Dr. Jerald Winakur

Fresh Air with Terry Gross from WHYY aired an interview today with Dr. Jerald Winakur on the topic of caring for an aging population and about dementia care (you can listen to the interview by accessing the link). The webpage also includes a link to the full-text contents a new narrative paper by Winakur entitled What Are We Going to Do with Dad?, which is published in the current issue of Health Affairs.
Anthony H. Risser | |

Wednesday, August 17, 2005

Abstract of the Day: Neuropsychology of Mild Cognitive Impairment (MCI)

Lopez OL, Becker JT, Jagust W, Fitzpatrick A, Carlson M, T DU, Breitner J, Lyketsos C, Jones B, Kawas C, & Kuller LH.
Neuropsychological characteristics of mild cognitive impairment subgroups. Journal of Neurology Neurosurgery and Psychiatry. 2005 Aug 15; [Epub ahead of print]

University of Pittsburgh, U.S.A., United States.

OBJECTIVES: To describe the neuropsychological characteristics of mild cognitive impairment (MCI) subgroups identified in the Cardiovascular Health Study (CHS) Cognition Study. METHODS: MCI was classified as follows: MCI Amnestic-type (MCI-AT): These were patients with documented memory deficits, with otherwise normal cognitive functions. MCI-Multiple cognitive deficits-type (MCDT): These patients had impairment in at least one cognitive domain (not including memory), or one abnormal test in at least two other domains, but who have not crossed the threshold for dementia. The MCI subjects did not have systemic, neurological, or psychiatric disorders that may have affected cognition. This study was conducted only in the CHS cases from Pittsburgh. RESULTS: MCI-AT (n=10) had worse verbal and non-verbal memory performance than MCI-MCDT (n=28), and normal controls (n=374). By contrast, MCI-MCDT had worse language, psychomotor speed, fine motor control, and visuoconstructional function performance than MCI-AT and normal controls. In addition, MCI-MCDT subjects had memory deficits, although they were less pronounced than those of the MCI-AT. Of the MCI-MCDT cases, 22 (78.5%) had memory deficits, and 6 (21.5%) did not. The MCI-MCDT with memory disorders had more language deficits than the MCI-MCDT without memory disorders. By contrast the MCI-MCDT without memory deficits had more fine motor control deficits than the MCI-MCDT with memory deficits. CONCLUSIONS: The most frequent form of MCI was the MCI-MCDT with memory deficits. However, the identification of memory impaired MCI groups, did not reflect the true prevalence of MCI in a population, since 16% of all MCI cases, and 21.5% of the MCI-MCDT cases did not have memory impairments. The study of idiopathic amnestic and non-anmestic forms of MCI is essential for our understanding the etiology of MCI.

PMID: 16103044 [PubMed - as supplied by publisher]
Anthony H. Risser | |

Tuesday, August 16, 2005

Human Embryonic Stem Cell Research: Pure Nerve Stem Cells

From the BBC:
Scientists make nerve stem cells
The world's first pure nerve stem cells made from human embryonic stem cells has been created by scientists at the University of Edinburgh.
Tuesday, 16 August 2005, 07:15 GMT 08:15 UK

It is hoped the newly-created cells will eventually help scientists find new treatments for diseases such as Parkinson's and Alzheimer's.

BBC science correspondent Pallab Ghosh said the cells should help researchers test the effectiveness of new drugs.

Stem cells are "master" cells that can become many kinds of tissue.

Nerve stem cells are those which help build the brain and central nervous system.

The university's Dr Steven Pollard said: "This is incredibly exciting in terms of curing disease.

"We may be able to create the disease in a dish. If we do that, we'll be able to better understand the disease and also to test drugs."
[ ... Read the full article ... ]
Anthony H. Risser | |

Portable, Wireless Brain Scanner

Smart Mobs points to a BBC report from yesterday about a Bluetooth-enabled portable brain scanner under development for use in acute stroke situations.
Anthony H. Risser | |

Obit: Conrad M. Riley, M.D.

From The Los Angeles Times:
Dr. Conrad M. Riley, 91; Pediatrician Identified Rare Genetic Condition
From Times Staff Reports
16 August 2005

Dr. Conrad Milton Riley, 91, a pediatrician who identified a rare genetic condition that occurs almost exclusively in Jewish children of Eastern European descent, died of an aortic aneurysm July 5 at the University of Colorado Hospital in Denver, his family said.

While working with Richard L. Day and others at Columbia University, he first described Riley-Day syndrome in 1949. The incurable neurological condition, which is caused by a defective gene inherited from both parents, is now known as familial dysautonomia. A key symptom is an inability to produce tears.

Riley was born in Worcester, Mass. He earned his bachelor's degree from Yale University in 1938 and his medical degree from Harvard University.

At the University of Colorado School of Medicine, Riley became a pioneer in the study of preventive medicine in the early 1960s. He also successfully pushed to increase the number of women and minority students admitted to the medical school and argued to liberalize Colorado's abortion law.
[ ... Read the full article ... ]
Anthony H. Risser | |

Abstract of the Day: Virtual Sims for Cognitive (Memory) Tasks - Neuropsychology on the Street

Titov N, Knight RG. A computer-based procedure for assessing functional cognitive skills in patients with neurological injuries: The virtual street. Brain Injury. 2005 May; 19(5): 315-322.

University of Otago, Dunedin, New Zealand.

PRIMARY OBJECTIVE: The aim of the present investigation was to construct and pilot test a computer-based multi-tasking procedure that could be used to assess the ability of patients with neurological damage to remember instructions in the real world. RESEARCH DESIGN: A simulated street scene was constructed from a network of photographs and sounds that patients could move through using a touch screen. Three patients with severe, moderate or mild cognitive impairment were assessed on a range of neuropsychological tests and three multi-tasking procedures based in the street. The performance of each patient was compared with that of a matched control. PROCEDURE: Three tests were administered, each of which involved 'walking' along the length of the street once. On the first test, participants were given up to five errands to remember while moving along the street. On the other two tests they were given three instructions to carry out repeatedly (e.g. 'Record the name of the nearest shop when you hear a dog bark'). In one condition they were given the three instructions on a sheet they could consult and in the other they had no list. OUTCOMES AND RESULTS: In each case the patient performed more poorly on the multi-tasking test than the matched control. The patients' performance on the computer-based tests was consistent with clinical descriptions of their memory-related deficits. CONCLUSION: The results illustrate the way in which computer presentation of naturalistic stimuli can be used to construct flexible and standardized tests of memory functioning that have enhanced ecological validity.

PMID: 16094778 [PubMed - in process]
Anthony H. Risser | |

Sunday, August 14, 2005

The Game Brain

Keep mentally active; chisel and tone those lobes:

Lifestyle May Be Key to Slowing Brain's Aging
Scientists Test Simple Ways to Keep One's Wits
By Rob Stein
The Washington Post
Sunday, August 14, 2005; Page A01

Like many Americans sliding into middle age, Kimberly McClain started worrying that her memory was beginning to slip.

"It was little things. I couldn't remember what I had for dinner the night before. I had to check to make sure I'd paid the insurance that month. I'd walk into a room and realize I had no idea why I was there," said the Los Angeles marriage counselor, who is 44.

So McClain started a program designed to help -- a detailed regimen that includes daily memory exercises.

"I'm much clearer now," McClain said. "I have no problem finding my keys. I can tell you what I had for dinner last night. I'm not walking into a room thinking, 'Why did I come in here?'"

McClain is among the increasing number of Americans who are performing mental calisthenics, taking Italian classes, deciphering crossword puzzles and hunting for other ways to try to keep their minds from fading.

[ ... Read the full article ... ]
Anthony H. Risser | |

Saturday, August 13, 2005

Dr. Heidelise Als and the NICU

From tomorrow's New York Times Sunday Magazine:

A Second Womb
The New York Times
Published: August 14, 2005

Read the article.

Dr. Heidelise Als, prematurity, and the contemporary neonatal ICU.
Anthony H. Risser | |

Friday, August 12, 2005

In The Weeklies: Human Rabies

This week's MMWR includes a case report and commentary about human rabies:

Human Rabies - Florida, 2004 in Morbidity and Mortality Weekly Report, 12 August 2005, 54(31).
Anthony H. Risser | |

Ion Channels for Everyone!

Eric Thomson at Neurochannels is hosting a discussion of the book, Hille, B. Ion Channels of Excitable Membranes (3rd edition). Sinauer Associates.

Learn everything you can about ion channels. They are your key to open up a basic understanding and appreciation of neural physiological functioning, biopsychology, and pharmacotherapeutics.
Anthony H. Risser | |

Thursday, August 11, 2005

Cognition-Enhancer Pharmaceuticals: Re-Airing Dr. Caplan

C-SPAN is re-airing Dr. Caplan's seminar on drugs to enhance cognitive performance on C-SPAN2 this evening at 6:34 pm Eastern Time. The program runs for 1:24 hours. Live feeds are available online at the C-SPAN website.

From yesterday's post on this topic:
C-SPAN has aired today a seminar presentation from the 9th of August 2005 by Dr. Arthur Caplan, bioethicist from the University of Pennsylvania, on the topic of the development of cognitively enhancing drugs.

Dr. Caplan is the Director of the Center of Bioethics at UPenn.

Check the C-SPAN website to determine re-air dates and whether the multimedia stream is made available for online viewing.

Anthony H. Risser | |

In The Weeklies: Cerebrovascular Events (CVAs)

In this week's Journal of the American Medical Association:

Robert G. Holloway, MD, MPH; Curtis G. Benesch, MD, MPH; W. Scott Burgin, MD; & Justine B. Zentner, MSN, ANP. Prognosis and decision making in severe stroke. Journal of the American Medical Association. 2005; 294: 725-733.
Anthony H. Risser | |

Obit: Thomas W. Langfitt, M.D.

From The Philadelphia Inquirer:
Thomas Langfitt; led Pew Charitable Trusts
By Gayle Ronan Sims
Philadelphia Inquirer Staff Writer
Posted on Tue, Aug. 09, 2005

Thomas W. Langfitt, 78, who during his tenure as president of the Pew Charitable Trusts transformed a little-known Philadelphia-based philanthropy into one of the nation's largest foundations, died of miliary tuberculosis Sunday at home in Wynnewood.

Dr. Langfitt - as a board member from 1979 and as chief executive officer from 1987 to 1994 - oversaw Pew's conversion from a family-run enterprise to the nation's fifth-largest foundation, one that championed such causes as childhood development, health care and the environment. Today, Pew has an endowment of $4.2 billion and ranks third in grant-making behind the Ford and W.K. Kellogg Foundations, with annual grants of more than $200 million.


Born in Clarksburg, W.Va., Dr. Langfitt developed an interest in medicine while accompanying his father, a general surgeon, on house calls.

He earned a bachelor's degree in biology in 1949 from Princeton University and a doctorate in 1953 from Johns Hopkins School of Medicine in Baltimore. Dr. Langfitt, who was drafted in 1946 and discharged the following year, was again called to active duty in 1955, the year he completed his residency in neurosurgery at Johns Hopkins. He served two years as an Army doctor.

When his hitch was up, Dr. Langfitt and his wife, Carolyn, stayed in Baltimore until 1961, when they moved to Merion after he was named head of neurosurgery at Pennsylvania Hospital. He later moved to the Hospital of the University of Pennsylvania, where he served as chairman of the neurosurgery department from 1968 to 1987.

"He was a leader in America in neurosurgery," Sean Grady, head of neurosurgery at HUP, said yesterday. "He is the modern-day father in the treatment of traumatic brain injury."

Dr. Langfitt, who moved to Wynnewood in the mid-1980s, was vice president of Penn's health affairs from 1974 to 1987, overseeing the hospital as well as the medical, dental, nursing and veterinary schools. As a researcher, Dr. Langfitt wrote more than 200 publications.

After retiring from Glenmede and Pew in 1994, the tall, courtly doctor returned to his medical roots. He became president of the College of Physicians of Philadelphia. There, he led the development of a Web-based medical information system ( ) designed to improve access to medical data among the poor.
[ ... Read the full article ... ]
Anthony H. Risser | |

Wednesday, August 10, 2005

Work in Progress: SenseCam - Potential as a Cognitive Aid Device?

The SenseCam is a Microsoft UK project.

Seems like something that might have some potential as a cognitive aid device, though the reality of neuropsychological deficits after known brain damage would suggest that a lot more work needs to be done on how it might actually be deployed. Use as a memory/attentional aid or enhancer for individuals without brain damage, but with heavy cognitive loads in their daily lives, seems easier to envision.

The sample images provided on the SenseCam webpage might be more reassuring if they were stamped with readable information (e.g., date/time)? Perhaps that's a background task that is available within the data stream but not presented in the examples.

It sure would be fun to play around with developing neurobehavioral apps of such devices! Good luck, Softies!
Anthony H. Risser | | |

Cognition-Enhancer Pharmaceuticals

C-SPAN has aired today a seminar presentation from the 9th of August 2005 by Dr. Arthur Caplan, bioethicist from the University of Pennsylvania, on the topic of the development of cognitively enhancing drugs.

Dr. Caplan is the Director of the Center of Bioethics at UPenn.

Check the C-SPAN website to determine re-air dates and whether the multimedia stream is made available for online viewing.
Anthony H. Risser | | |

Tuesday, August 09, 2005

Neuropsychology News

The Summer 2005 newsletter of the Neuropsychology Division of the American Psychological Association (APA) is now available online. It includes information about its upcoming conference next week at the larger APA Annual Convention in Washington, D.C.
Anthony H. Risser | | |

Business World: Boston Scientific, Wingspan Stent System, & Stroke

From the Boston Business Journal website:
Boston Scientific stent system gains limited approval
Boston Business Journal
11:16 AM EDT Tuesday

Boston Scientific Corp. has gotten limited regulatory approval for a stent system to treat a stroke.

The Natick, Mass. company (Nasdaq: BSX) announced Tuesday that it had gained a humanitarian device exemption approval from the U.S. Food and Drug Administration for its new Wingspan Stent System and catheter.

The device is designed to treat accumulated plaque in brain arteries and potentially prevent what is known as an ischemic stroke, which is caused by a blocked blood vessel that can deprive the brain of oxygen. Wingspan removes plaque build-up that can block the blood. Approval is based on a 45-patient study conducted at 12 sites in Europe and Asia.
[ ... Read the full article ... ]
Anthony H. Risser | | |

Sunday, August 07, 2005

Predicting Stimuli from fMRI Data

Though the headline and subhead they use are unfortunately over-dramatic, this from the BBC:
'Thoughts read' via brain scans
The researchers monitored activity in the brain. Scientists say they have been able to monitor people's thoughts via scans of their brains.

Teams at University College London and University of California in LA could tell what images people were looking at or what sounds they were listening to.

The US team say their study proves brain scans do relate to brain cell electrical activity.

The UK team say such research might help paralysed people communicate, using a "thought-reading" computer.

In their Current Biology study, funded by the Wellcome Trust, people were shown two different images at the same time - a red stripy pattern in front of the right eye and a blue stripy pattern in front of the left.

The volunteers wore special goggles which meant each eye saw only what was put in front of it.

In that situation, the brain then switches awareness between both images, sometimes seeing one image and sometimes the other.

While people's attention switched between the two images, the researchers used fMRI (functional Magnetic Resonance Imaging) brain scanning to monitor activity in the visual cortex.

It was found that focusing on the red or the blue patterns led to specific, and noticeably different, patterns of brain activity.

The fMRI scans could reliably be used to predict which of the images the volunteer was looking at, the researchers found.


The US study, published in Science, took the same theory and applied it to a more everyday example.

They used electrodes placed inside the skull to monitor the responses of brain cells in the auditory cortex of two surgical patients as they watched a clip of "The Good, the Bad and the Ugly".

They used this data to accurately predict the fMRI signals from the brains of another 11 healthy patients who watched the clip while lying in a scanner.
[ ... Read the full article ... ]
Anthony H. Risser | | |

Friday, August 05, 2005

The Game Brain (continued)

Illustrator Paige Pooler has a cute illustration on her blog Eyes Wide Apart today on the topic of aging which seems appropo to the spirit of The Game Brain. (grin)
Anthony H. Risser | | |

In The Weeklies: Alzheimer Disease Treatments

The 06 August 2005 issue of the British Medical Journal includes the full-text contents of this paper reviewing the pharmacological treatment of Alzheimer disease:
Hanna Kaduszkiewicz, Thomas Zimmermann, Hans-Peter Beck-Bornholdt, & Hendrik van den Bussche. Cholinesterase inhibitors for patients with Alzheimer's disease: Systematic review of randomised clinical trials. British Medical Journal;  2005; 331: 321-327 (6 August) [doi:10.1136/bmj.331.7512.321]

Department of Primary Medical Care, Center of Psychosocial Medicine, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany

Objectives. Pharmacological treatment of Alzheimer's disease focuses on correcting the cholinergic deficiency in the central nervous system with cholinesterase inhibitors. Three cholinesterase inhibitors are currently recommended: donepezil, rivastigmine, and galantamine. This review assessed the scientific evidence for the recommendation of these agents.

Data sources. The terms "donepezil", "rivastigmine", and "galantamine", limited by "randomized-controlled-trials" were searched in Medline (1989-November 2004), Embase (1989-November 2004), and the Cochrane Database of Systematic Reviews without restriction for language.

Study selection. All published, double blind, randomised controlled trials examining efficacy on the basis of clinical outcomes, in which treatment with donepezil, rivastigmine, or galantamine was compared with placebo in patients with Alzheimer's disease, were included. Each study was assessed independently, following a predefined checklist of criteria of methodological quality.

Results. 22 trials met the inclusion criteria. Follow-up ranged from six weeks to three years. 12 of 14 studies measuring the cognitive outcome by means of the 70 point Alzheimer's disease assessment scale—cognitive subscale showed differences ranging from 1.5 points to 3.9 points in favour of the respective cholinesterase inhibitors. Benefits were also reported from all 12 trials that used the clinician's interview based impression of change scale with input from caregivers. Methodological assessment of all studies found considerable flaws—for example, multiple testing without correction for multiplicity or exclusion of patients after randomisation.

Conclusion. Because of flawed methods and small clinical benefits, the scientific basis for recommendations of cholinesterase inhibitors for the treatment of Alzheimer's disease is questionable.
[ ... Read the full research article ... ]
Anthony H. Risser
| | |

Apple Advertises the Brain (continued)

Mind Hacks provides an interesting commentary about this Apple article (see yesterday's post of the same title).
Anthony H. Risser | | |

Carl Zimmer Re-Aired on WHYY's Fresh Air

While looking at the recent shows of Terry Gross's interview show, I noticed that she recently re-aired a February 2004 interview with Carl Zimmer about his book Soul Made Flesh (the story of Thomas Willis and the founding of neurology).

The audio stream for this interview can be found on this page of the NPR website.

I recommend this book for undergraduate students taking their first neuroscience or biopsychology course as an excellent and very readable account of an aspect of history too often limited just to a presentation of the thoughts of Rene Descartes.
Anthony H. Risser | | |

Thursday, August 04, 2005

The Game Brain

There is an acceleration of interest in promoting cognitive and neuropsychological 'exercise' for a healthy brain, especially over the course of aging. Though most mainstream-media articles about this report it as a new phenomenon, it really is not. Over the past 25 years, if not longer, neuropsychologists have been recommending such activities for subsets of relevant patients that they have examined.

What is new is the healthy burst of new energy and interest and - one hopes - a healthy dose of clinical-trials testing to assure that this 'exercise' actually has a firm foundational basis to it and a careful mapping against specific individual attributes - especially if someone is going to have to foot the bill for access to it. Even without these newly emerging approaches, it is a given of common sense that it is better to be an active person than an inactive one - just keep those brain juices flowing, folks!

I'd like to think that a crossword puzzle a day - like the proverbial apple - can keep the doctor away. For these newer and more ambitious approaches, a critical research eye and the professional eagerness to test these approaches with objectivity will take us far.

A new article at includes quotes from Drs. Elkhonon Goldberg and Margaret Gatz, as well as reference to the excellent programmatic research of "The Nun Study." Here's the link:

Brain Workouts May Tone Memory
By Joanna Glasner
Wired News
02:00 AM Aug. 04, 2005 PT

[ ... Read the article ... ]
Anthony H. Risser | | |

Apple Advertises the Brain

Apple's website added an article entitled Streamlining Neuroimaging yesterday, which outlines the work of Dr. Nouchine Hadjikhani and her use of the NeuroLens software app in visualizing the results of functional neuroimaging.
Anthony H. Risser | | |

Olfactory-Visual Cross-Modal Modulation

The full text of this article is available at the American Psychological Association (APA) website:
George Andrew Michael, PhD, Université Lumière-Lyon 2, and Laurence Jacquot, PhD, Jean-Louis Millot, PhD, and Gérard Brand, PhD, Université de Franche-Comté. Ambient odors influence the amplitude and time course of visual distraction.. Behavioral Neuroscience, 2005, 119 (3), 708-715.

Behavioral performance was examined in a task of attentional capture by luminance under conditions of ambient odors (phenyl ethyl alcohol [PEA], olfactory stimulus, and allyl isothiocyanate [AIC], mixed olfactory/trigeminal stimulus). The AIC increased the amplitude and duration of capture, whereas the presence of PEA led capture to disappear. Furthermore, the PEA caused a general slowing in the speed of information processing. The amplitude and time course of capture were correlated to the irritating components of these odorants, whereas a control experiment showed that the general slowing caused by the PEA was correlated to a drop-off of the subjects’ arousal level. These results suggest that ambient odors may exert differential influence of visual-attentional processes and that this influence may depend on the odor’s properties.
Obtain the full text of the article, as available from the APA Public Affairs Office in .pdf format.

Read the APA press release.
Anthony H. Risser | | |

Wednesday, August 03, 2005

Business World: Biogen Idec, Protein Design Labs, & Daclizumab

From The Boston Globe:
Biogen cuts deal to refill drug lineup
Biotech to pay Calif. firm for rights to help develop MS treatment, 2 others
By Jeffrey Krasner, Globe Staff
The Boston Globe
August 3, 2005

Making good on a promise to use a war chest of cash to replenish its drug pipeline, Biogen Idec Inc. of Cambridge yesterday said it was licensing three promising drug candidates from Protein Design Labs Inc.

In exchange for rights to codevelop three antibodies midway through human trials, Biogen Idec will pay Protein Design Labs $40 million, and buy $100 million of the Fremont, Calif., company's stock. If the three drug candidates are proven effective treatments for various diseases, Biogen Idec could pay an additional $660 million.

The deal includes codevelopment rights for Daclizumab, an antibody that has shown promise in preventing transplanted organ rejection and in treating asthma and multiple sclerosis. Positive news about Daclizumab trials underway could bolster Biogen Idec's multiple sclerosis franchise, which has faltered this year since the voluntary suspension of Tysabri, an MS treatment that resulted in unexpected illnesses in several patients who used it during clinical trials.
[ ... Read the full article ... ]
Anthony H. Risser | | |

"Learning, Memory and the Brain" on NPR

A radio interview with Dr. Larry Squire on the topic of "Learning, Memory and the Brain" aired on NPR last week. An audio stream of the show can be found on the NPR site, as well as a podcast link.
Anthony H. Risser | | |

Tuesday, August 02, 2005

"You have three wrists. You should have three hands.": Neurological Denial and Neglect

Today's New York Times has a short piece on the neurological disorders of denial and neglect. If you examine individuals in acute neurological settings, some very dramatic and extraordinary examples of this can be observed on occasion and are truly unforgettable. Fortunately, it is common to see improvements in some of the more dramatic manifestations of this over the course of an individual's acute recovery, though residual problems may persist.

Discovering That Denial of Paralysis Is Not Just a Problem of the Mind
The New York Times
Published: August 2, 2005

[ ... Read the article ... ]
Anthony H. Risser | | |

Well Worth Reading: Dr. Michael Gazzaniga on Split-Brain Research

The new August 2005 issue of Nature Reviews Neuroscience includes an essay by Dr. Michael Gazzaniga about split-brain research. The article is not available in full text online, but worth getting a copy of for a good read!

Here is the abstract:
Michael S. Gazzaniga. Forty-five years of split-brain research and still going strong. Nature Reviews Neuroscience; 2005: 6, 653-659. [doi:10.1038/nrn1740]

Forty-five years ago, Roger Sperry, Joseph Bogen and I embarked on what are now known as the modern split-brain studies. These experiments opened up new frontiers in brain research and gave rise to much of what we know about hemispheric specialization and integration. The latest developments in split-brain research build on the groundwork laid by those early studies. Split-brain methodology, on its own and in conjunction with neuroimaging, has yielded insights into the remarkable regional specificity of the corpus callosum as well as into the integrative role of the callosum in the perception of causality and in our perception of an integrated sense of self.
If you access the Roger Sperry link I placed into the abstract, you will find a page of .pdf copies of Sperry publications, including a number of original papers on this split-brain research.
Anthony H. Risser | | |