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 ... ]