Monday, January 31, 2005

Bird Brains!

From tomorrow's New York Times:

Minds of Their Own: Birds Gain Respect
By SANDRA BLAKESLEE
The New York Times
Published: February 1, 2005

Birdbrain has long been a colloquial term of ridicule. The common notion is that birds' brains are simple, or so scientists thought and taught for many years. But that notion has increasingly been called into question as crows and parrots, among other birds, have shown what appears to be behavior as intelligent as that of chimpanzees.

The clash of simple brain and complex behavior has led some neuroscientists to create a new map of the avian brain.

Today, in the journal Nature Neuroscience Reviews, an international group of avian experts is issuing what amounts to a manifesto. Nearly everything written in anatomy textbooks about the brains of birds is wrong, they say. The avian brain is as complex, flexible and inventive as any mammalian brain, they argue, and it is time to adopt a more accurate nomenclature that reflects a new understanding of the anatomies of bird and mammal brains.

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

Nanotechnology and the Brain

Nanomedicine's Promise Is Anything but Tiny
By Rick Weiss
The Washington Post
Monday, January 31, 2005; Page A08
[ ... Read the full article ... ]

Qdots and amphiphiles and other possibilities...

[snip]

Injured nerves do not regenerate easily, and the little healing that does occur is often inhibited by scar tissue formation. Samuel Stupp and John Kessler at Northwestern University in Chicago are using nanotechnology to overcome those hurdles.

They made tiny rod-like molecules called amphiphiles, each of which is capped by a cluster of amino acids known to spur the growth of neurons and prevent scar tissue formation. The molecules are designed to remain suspended in a few drops of liquid until they come in contact with living cells. At that point they spontaneously arrange themselves like spokes in a wheel, and then further assemble into spaghetti-like nanofibers a few thousandths the thickness of a human hair. The nerve-healing amino acids end up arranged nicely on the fibers' surface.
~
Here is a link to the research mentioned above: The Stupp Lab at Northwestern

In Vivo Visual Cortex Neuronal Activity

"Reid Lab Movies" of cat and rat visual cortex during visual stimulation, at: http://neuro.med.harvard.edu/site/reidweb/movies.html

Saturday, January 29, 2005

Retinal Cells and Melanopsin

From the BBC:

Doctors Make Eye Cells See Light
Scientists have found how to make eye cells sensitive to light, opening new ways to treat some forms of blindness.

Experts at Imperial College London teamed up with colleagues at the University of Manchester to study a protein, melanopsin.

Activating melanopsin in cells that do not normally use it made them sensitive to light, they told [the scientific journal] Nature.

[snip]

But experiments on mice which have had their rods and cones destroyed, reveals that other cells in the retina also have some form of light response.

Scientists have suspected that melanopsin is important to all of these 'light sensitive' cells.

The London-Manchester team set out to study melanopsin in more detail.

In mice, they found turning on a gene for melanopsin caused nerve cells to work like photoreceptors.

Although making cells in the eye responsive to light is not a cure for blindness, the researchers are working with engineers to develop prosthetic retinas that might help people with sight disorders to see more clearly.

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

Tuesday, January 25, 2005

The Brain in Nonfiction

From tomorrow's New York Times, a book review of two new nonfiction books about the brain:

The Brain: False Assumptions and Cruel Operations
By WILLIAM GRIMES
The New York Times
Published: January 26, 2005

Reviews of these two books:
POSTCARDS FROM THE BRAIN MUSEUM
The Improbable Search for Meaning in the Matter of Famous Minds

By Brian Burrell
Illustrated. 356 pages. Broadway Books. $24.95.

THE LOBOTOMIST
A Maverick Medical Genius and His Tragic Quest to Rid the World of Mental Illness

By Jack El-Hai
Illustrated. 362 pages. John Wiley & Sons. $27.95
Read the book review (free registration required)

ApoE (Apolipoprotein E) Impact on Memory in Healthy Older Adults

The following study (see press release below and obtain the free full-text content of the research paper at full text) has received a good deal of media attention over the past couple of days.

Date: January 23, 2005
Contact: Public Affairs Office
American Psychological Association
(202) 336-5700

OLDER PEOPLE WITH THE “ALZHEIMER’S GENE” FIND IT HARDER TO “REMEMBER TO REMEMBER” EVEN IF THEY’RE HEALTHY

New Mexico study finds surprisingly strong impact of genetic variation

Washington — Carrying the higher-risk genotype for Alzheimer’s disease appears to render even healthy older people subject to major problems with prospective memory, the ability to remember what to do in the future. For the group studied, this could affect important behaviors such as remembering to take medicine at a certain time or getting to a doctor’s appointment. The research appears in the January issue of Neuropsychology, which is published by the American Psychological Association.

People with this genotype have a certain variety, or allele, of a gene called ApoE (for Apolipoprotein E), which switches on production of a protein that helps carry cholesterol in the blood. ApoE has three alleles and about one out of five people carry the e-4 allele. It makes homozygous carriers, who carry this variation on both of their ApoE genes, eight times as likely to develop Alzheimer’s disease as non-carriers. Heterozygous carriers, who carry the high-risk variation only on half the pair, have a three-fold higher risk. Neuro- psychologists have looked at the episodic, or retrospective, memory, of e-4 carriers, especially for recent events. This study was the first to look at their prospective memory.

At the University of New Mexico, a group of 32 healthy, dementia-free adults between ages of 60 and 87 were drawn from a larger study of aging and divided evenly between people with and people without the e-4 allele.

On a task in which participants were asked to remember to write a certain word when they saw a target word, the carriers showed significantly worse prospective memories. Far more often than non-carriers, they failed to remember to write down the desired word when they were supposed to – in other words, they forgot to do what they meant to do, when they meant to do it.

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

Saturday, January 22, 2005

Imaging Applications in Neuropsychology

The January 2005 newsletter of the American Psychological Association's Division 40 (Clinical Neuropsychology) is devoted to several papers exploring functional neuroimaging. The newsletter is available in .pdf format at http://www.div40.org/newsletter.html.

Reminyl (galantamine hydrobromide) (continued)

Safety Concerns Reported on J.& J. Alzheimer's Drug
By ANDREW POLLACK
New York Times
Published: January 22, 2005

Regulators are reviewing the safety of the Alzheimer's disease drug Reminyl after data from two clinical trials indicated that people taking the drug had a much higher death rate than those taking a placebo.

The review was announced yesterday by Johnson & Johnson, which said it was in discussions with the Food and Drug Administration and regulators in Europe and Canada.

The trials, which involved about 2,000 patients in 16 countries, were looking at whether Reminyl could be used to treat mild cognitive impairment, a form of memory loss that is often a precursor to Alzheimer's disease. Reminyl is approved in 69 countries as a treatment for mild to moderate Alzheimer's but not for mild cognitive impairment.

In the trials, which lasted two years, 15 patients taking Reminyl died compared with 5 taking the placebo. There were various causes of death but many were from heart attacks and strokes, a company spokeswoman, Carol Goodrich, said.

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

"Epileptic" ("L'Ascension du Haut-Mal")

The Sunday Book Review in tomorrow's New York Times includes a review of a recently translated graphic memoir about a family of a person with epilepsy in the 1960s:
'Epileptic': Disorder in the House
by David B. (pseudonym Pierre-Francois Beauchard)
By RICK MOODY
New York Times
23 January 2005

[snip]

Historians of the graphic form will observe that Spiegelman, Sacco and others (one stunning example is the recent prose/graphic hybrid ''Diary of a Teenage Girl'' by Phoebe Gloeckner) have all experimented with autobiography in their work, but in the case of ''Epileptic'' the autobiographical impulse has, in my view, more to do with what's happening in French writing these days, namely l'autofiction. If, against the advice of conservatives, you should travel to the Paris of 2005, you would find that the traditional roman a clef of French literature has lately given way to a cottage industry of remorselessly literary accounts of the intimate lives of French nationals. David B.'s story, in broad outline, is about the desperate attempts of his family to deal with his older brother's chronic epilepsy; it is consonant with the confessional literary impulse in French letters, but as befits the graphic genre, it also takes liberties with the form. The young narrator, Pierre-Francois, for example, is obsessed with military history, and therefore the particulars of his brother's story are interwoven with the young artist's myriad imaginings of the invasions of the Mongols, his grandfather's experiences in World War I, and tales of the Algerian war and the French Resistance.

[snip]

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

Friday, January 21, 2005

Reminyl (galantamine hydrobromide)

From the New York Times:

Johnson & Johnson Reports Reminyl Deaths
By THE ASSOCIATED PRESS
Published: January 21, 2005
Filed at 5:08 p.m. ET

RARITAN, N.J. (AP) -- Patients taking Alzheimer's drug Reminyl in a test for another use had higher death rates than those taking a placebo, Johnson & Johnson Pharmaceutical Research & Development LLC announced Friday.

The patients had mild cognitive impairment, and the J&J company is no longer pursuing Reminyl as a treatment for the condition and has not submitted any applications for such use, spokeswoman Carol Goodrich said.

Reminyl was approved in 2001 as a treatment for mild to moderate Alzheimer's disease. The higher death rate was not observed in Alzheimer's trials, Goodrich said.
[ ... Read the full article ...] (free registration required)

Forthcoming Event: St. Louis, February 2005

The 33rd Annual Meeting of the International Neuropsychological Society (INS) will be held from the 2nd of February 2005 through the 5th at the Adam's Mark Hotel, located in downtown St. Louis, Missouri.

Information about the conference can be found on the meeting's homepage.

Wednesday, January 19, 2005

Neuroeconomics

How we choose
A new branch of brain science tries to understand human decision-making, but also may have the power to influence our actions
By Carolyn Y. Johnson
Boston Globe
January 18, 2005

Human life is a string of seemingly straightforward choices -- getting dressed, picking up a newspaper, and beginning to read this article -- that are surprisingly hard to predict. What sweater will people pull on, which newspaper will they choose, and what will they read first?

As advertisers, financial analysts, and scientists have long known, it's hard to say. Human inconsistency rules.

Now, a budding field called "neuroeconomics" seeks to explain exactly how people make up their minds by using the latest imaging technologies to examine the grayish lump of brain tissue where each decision begins. The researchers, migrs [sic] from fields like psychology, neuroscience, and economics, hope to build a theory of human behavior that starts at the level of single nerve cells but can describe the choices individuals make, and even how markets work.

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

Tuesday, January 18, 2005

Parkinson Disease: LRRK2, PARK8, and Dardarin

From the BBC:

Target found for Parkinson's test

A gene mutation which could be behind one in 25 cases of Parkinson's disease has been discovered by scientists.

It is hoped the findings could lead to the earlier detection of the disease and the development of treatments.

Three separate studies by US, UK and Dutch research teams are published in The Lancet medical journal.

Parkinson's, for which there is no cure, is a degenerative disease in the part of the brain controlling movement and affects 3% of people over 75.

Read the full report
~

Here is a link to the 15 January 2005 issue of The Lancet, which includes citations and abstracts of the aforementioned studies, as well as editorial comment.

Monday, January 17, 2005

Watch Out: Under-recognized, Under-treated Means Ad Blitz

An interesting piece on what's about to hit consumers: the marketing of Lunesta (eszopiclone):

You May Want to Sleep on It
Enter the Next 'Miracle' Drug: A Sleeping Pill You Can Take Long-Term. Ads for Lunesta Won't Likely Give That Theme a Rest. This Time Will Consumers Be More Leery?
By Sandra G. Boodman
Washington Post
Tuesday, January 18, 2005; Page HE01

Read the full article (free registration required)

Sunday, January 16, 2005

Blink!

Malcolm Gladwell's new book, Blink, is now available.

Today's New York Times Book Review features a review of the book, written by David Brooks. The review is available here (free registration required).

Previous discussion of Blink and Gladwell's thoughts about cognition and so-called "thin-slicing" can be found in an 02 October 2004 BrainBlog entry (October archives).
~
Malcolm Gladwell's website is www.gladwell.com

Wednesday, January 12, 2005

In The News: Nifrolidine

This research study noted below been reported today in some media, in terms of potential implications for the diagnosis of Alzheimer disease. Here is the study's abstract, which is more technical in content and less speculative in nature:

Chattopadhyay S, Xue B, Collins D, Pichika R, Bagnera R, Leslie FM, Christian BT, Shi B, Narayanan TK, Potkin SG, Mukherjee J.
Synthesis and Evaluation of Nicotine {alpha}4{beta}2 Receptor Radioligand, 5-(3'-18F-Fluoropropyl)-3-(2-(S)-Pyrrolidinylmethoxy)Pyridine, in Rodents and PET in Nonhuman Primate. Journal of Nuclear Medicine. 2005 Jan; 46(1): 130-140.

Department of Psychiatry and Human Behavior. Brain Imaging Center, University of California, Irvine, California.

Nicotine alpha(4)beta(2) receptor subtypes are implicated in the study of Alzheimer's disease, schizophrenia, substance abuse, lung cancer, and other disorders. We report the development and evaluation of a putative antagonist, 5-(3'-fluoropropyl)-3-(2-(S)-pyrrolidinylmethoxy)pyridine (nifrolidine) as a PET agent for nicotine alpha(4)beta(2) receptors. METHODS: In vitro binding affinity of nifrolidine was measured in rat brain slices labeled with (125)I-iodoepibatidine or (125)I-bungaratoxin. Selectivity of binding was measured in the presence of cytisine. (18)F radiolabeling was performed by reacting the tosylate precursor with (18)F-fluoride followed by deprotection. In vitro autoradiographic studies in rat brain slices with 5-(3'-(18)F-fluoropropyl)-3-(2-(S)-pyrrolidinylmethoxy)pyridine ((18)F-nifrolidine) were read on a phosphor imager. Rats were injected with (18)F-nifrolidine (3.7 MBq each), and brain regions were counted at various times (2-120 min). Blocking studies were performed by subcutaneous injection of nicotine (10 mg/kg). A PET study of (18)F-nifrolidine (approximately 148 MBq) was performed on an anesthetized rhesus monkey using a high-resolution scanner. RESULTS: In vitro binding affinity of nifrolidine exhibited an inhibition constant of 2.89 nmol/L for the alpha(4)beta(2) sites. Radiosynthesis and high-performance liquid chromatography purifications yielded the product in approximately 20%-40% decay-corrected radiochemical yield to provide (18)F-nifrolidine specific activities of approximately 111-185 GBq/mumol. In vitro autoradiography in rat brain slices revealed selective binding of (18)F-nifrolidine to the anteroventral thalamic nucleus, ventral posteriomedial thalamus, dorsolateral geniculate, and, to a lesser extent, cortex and striata, which are known to contain alpha(4)beta(2) sites. This specific binding was completely abolished by 300 mumol/L nicotine. Ex vivo rat brain distribution studies indicated selective binding in the thalamus with a maximal thalamus-to-cerebellum ratio of approximately 3. The PET study revealed selective maximal uptake (0.01% injected dose/mL) in regions of the thalamus (anteroventral and anteromedial thalamus, ventrolateral thalamus) and extrathalamic regions such as cingulate gyrus, lateral geniculate, temporal cortex, and frontal cortex. CONCLUSION: Binding of (18)F-nifrolidine to alpha(4)beta(2) receptor-rich regions in rats and monkeys indicates promise as a PET agent. Additionally, the thalamus-to-cerebellum ratio approached a plateau of 1.7 in 120 min, indicating relatively faster kinetics compared with previously reported imaging agents.

PMID: 15632043 [PubMed - as supplied by publisher]

Tuesday, January 11, 2005

The Fictional Neuroscientist

Boston Globe columnist Alex Beam on Tom Wolfe's new novel:

Escaping the wrath of Wolfe

By Alex Beam, Globe Columnist
January 11, 2005

Is Dartmouth cognitive neuroscientist Michael Gazzaniga in line to become the new Epictetus? Anything is possible.

Epictetus is the Greek Stoic philosopher who enjoyed a brief resurgence of popularity in 1998, when Tom Wolfe published his best-selling novel ''A Man in Full." One of Wolfe's characters improbably converted to the teachings of Mr. E., ''a philosopher who had been stripped of everything, imprisoned, tortured, enslaved, and threatened with death," per Wolfe.

Now, as first noted by Professor Gazzaniga's local paper, the Lebanon, N.H., Valley News, Mr. G. is just about the only academic to emerge unscathed in Wolfe's latest satirical outing, ''I Am Charlotte Simmons," which purports to be an expos of contemporary college life. The mention of Gazzaniga is ''noteworthy," the paper reports, ''because the rest of Wolfe's book rips apart faculty poseurs, smooth-talking college presidents and drunken frat boys.
[ ... Read the full column ... ]

Monday, January 10, 2005

Rats in the News

You've probably read the news story which has received a good deal of press over the past day about a psychological investigation into language-patterning abilities in rats. The full-text reprint of this paper is available at this time on the website of the American Psychological Association, along with the original press release. The link for the full-text article is: http://www.apa.org/releases/speech_article.pdf

Date: January 9, 2005
Contact: Public Affairs Office
American Psychological Association (APA)
(202) 336-5700

RATS CAN TELL TWO LANGUAGES APART FROM SPEECH CUES, SHARING AN ABILITY WITH HUMANS AND MONKEYS

They’re the third type of mammal shown to have this skill

WASHINGTON — Mammals other than humans can distinguish between different speech patterns. Neuroscientists in Barcelona report that rats, like humans (newborn and adult) and Tamarin monkeys, can extract regular patterns in language from speech (prosodic) cues. The report appears in the January issue of the Journal of Experimental Psychology: Animal Behavior Processes, which is published by the American Psychological Association.

This study of 16 rats per each of four conditions showed that they were able to pick up enough cues from the rhythm and intonation of human speech to tell spoken Dutch from spoken Japanese. After the researchers trained rats to press a lever when hearing a synthesized five-second sentence in Dutch or Japanese, they tested the rats’ response to the alternative language. Rats rewarded for responding to Japanese did not respond to Dutch and vice versa. They pressed the lever only for the language to which they’d been exposed. What’s more, the rats generalized the ability to differentiate to new Dutch and new Japanese sentences they had not heard before.

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

Musing About The Sound Of Amygdala

Ob-La-Di, Ob-La-Da, Amygdala: Word as Earworm
By JAMES GORMAN
The New York Times
Published: January 11, 2005

My infatuation with the amygdala has led me to wonder where aphasia and amusia overlap, a subject that neurologists have been investigating for many years. Damage to the brain can interfere with spoken language - aphasia. But it can also harm the ability to hear and produce melody.

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

Friday, January 07, 2005

In The Weeklies

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

British Medical Journal
08 January 2005

Risk of ischaemic stroke in people with migraine: systematic review and meta-analysis of observational studies by Etminan, Takkouche, Isorna, & Samii.

New England Journal of Medicine
06 January 2005

Neurologic and developmental disability at six years of age after extremely preterm birth by Marlow and colleagues. The issue also has editorial commentary on this research paper.

Limiting stroke-induced damage by targeting an acid channel by Benveniste & Dingledine.

Nature
06 January 2005

A mechanism for impaired fear recognition after amygdala damage by Adolphs and colleagues.
Excerpt:

Ten years ago, we reported that SM, a patient with rare bilateral amygdala damage, showed an intriguing impairment in her ability to recognize fear from facial expressions. Since then, the importance of the amygdala in processing information about facial emotions has been borne out by a number of lesion and functional imaging studies. Yet the mechanism by which amygdala damage compromises fear recognition has not been identified. Returning to patient SM, we now show that her impairment stems from an inability to make normal use of information from the eye region of faces when judging emotions, a defect we trace to a lack of spontaneous fixations on the eyes during free viewing of faces. Although SM fails to look normally at the eye region in all facial expressions, her selective impairment in recognizing fear is explained by the fact that the eyes are the most important feature for identifying this emotion. Notably, SM's recognition of fearful faces became entirely normal when she was instructed explicitly to look at the eyes. This finding provides a mechanism to explain the amygdala's role in fear recognition, and points to new approaches for the possible rehabilitation of patients with defective emotion perception.

Monday, January 03, 2005

Alternative to Deep-Brain Stimulation in Parkinson Disease?

From Reuters:
Brain Surface Stimulation May Ease Parkinson's
Mon Jan 3, 2005 06:22 PM GMT
By Anne Harding

NEW YORK (Reuters Health) - Electrical stimulation of regions deep in the brain has become fairly common in recent years for treating Parkinson's disease symptoms, but there may be a simpler and safer alternative.

The results of a study in baboons suggest that stimulation of the motor control area on the brain's surface works too.

Delivering electrical stimulation to deep brain regions has been shown to help some people with Parkinson's, but the skill required to implant the electrodes, as well as the risks of electrode misplacement, have limited the use of this procedure.

Parkinson's symptoms have been tied to abnormal electrical activity in neurons in the main area that controls movement -- the motor cortex -- which is in the outer layer of the brain, a French team notes in the medical journal Neuron.
[ ... Read the full article ... ]

Saturday, January 01, 2005

2005

Happy New Year!