Medicine & Health
edyong | August 4, 2008For the first time, scientists have developed drugs that mimics the effects of endurance exercise. With the aid of two chemicals, Vihang Narkar, Ronald Evans and colleagues from the Salk Institute managed to turn regular lab rodents into furry Paula Radcliffes - mighty mice that were capable of running further and for longer than their peers. One of the drugs only worked in combination with exercise, but the other managed to boost stamina without it.
Using drugs to boost performance isn't a new development. Steroids can help body-builders to build their bodies, while giving athletes an extra…
neurophilosophy | August 3, 2008
Last month, I travelled to Bristol to meet 37-year-old Heather Perry, one of a very small number of people to have voluntarily undergone trepanation for non-medical reasons. As we ate a pub lunch, I asked Heather about her experience. Below is a transcript of our conversation.
M: How did you first hear about trepanation, and why did you decide to have it done?
HP: The first time I heard about trepanation was when I was a kiddie. I was really into Bob Dylan and John Lennon, and I remembered that Lennon had mentioned that he wanted it done. He had spoken to Bart Huges about it, and Bart had…
neurophilosophy | July 24, 2008
Depression is a common neuropsychiatric disorder which affects at least 1 in 7 adults. The condition can have a major effect on patients' quality of life, and is a major cause of both disability and suicide.
Many patients with depression can be treated effectively with antidepressant medications, such as the specific serotonin re-uptake inhibitor (SSRI) fluoxetine (more popularly known as Prozac). However, a significant proportion of patients - up to 20% - do not respond to these drugs, or to other forms of treatment.
Now a study published online in the journal Biological Psychiatry suggests…
neurophilosophy | July 17, 2008
This image comes from Marc Steinmetz's photoessay about plastination, the tissue preservation technique invented by the controversial German anatomist Gunther von Hagens.
Plastination involves replacing the water and fats in the tissues with silicon or some other polymer. The specimen is first fixed in alcohol, then dehydrated, impregnated with the polymer and finally allowed to harden.
In the photograph above, the coronal brain sections have been placed under ultraviolet light for curing. The black stains visible in the slices show the sites of a massive haemorrhage which killed this…
edyong | July 16, 2008
Many measures to curb the obesity epidemic are aimed at young children. It's a sensible strategy - we know that overweight children have a good chance of becoming overweight adults. Family homes and schools have accordingly become critical arenas where the battle against the nation's growing waistlines is fought. But there is another equally important environment that can severely affect a person's chances of becoming overweight, but is more often overlooked - the womb.
Overweight parents tend to raise overweight children but over the last few years, studies have confirmed that this…
neurophilosophy | July 16, 2008
This three-dimensional reconstruction of an amyloid fibril (found at Discover) was created by Nikolaus Grigorieff and his colleagues at Brandeis University, by computer processing of a transmission electron cryomicroscopy image. It is the most detailed image yet of the abnormally folded protein which accumulates to form the senile plaques that are a pathological hallmark of Alzheimer's Disease.
The fibrils consist of a protein fragment called amyloid-beta 1-40, an insoluble forty amino acid polypeptide generated by the sequential actions of a number of enzymes on the amyloid precursor…
neurophilosophy | July 14, 2008
Back in January, the Daily Mail reported on "the helmet that could turn back the symptoms of Alzheimer's." The device is pictured above, held by its inventor, a British GP called Gordon Dougal. It consists of 700 light-emitting diodes which transmit near-infrared light into the brain and can, according to Dougal, stimulate hippocampal neurogenesis, and therefore reverse the cognitive decline associated with Alzheimer's, if worn for 10 minutes a day for about a month.
When the story first came out, David Gorski did a brilliant job of explaining why it is probably too good to be true: Dougal'…
edyong | July 14, 2008Evolution dances to the tune of death. Killers - be they predators, diseases or competitive peers - can radically shape a species' life cycles by striking down individuals of a certain age. The survivors respond by changing their "life histories" - a collection of traits that defines their reproductive cycles, including how often they breed, when they start to do so and how many young they have.
If an animal's adult life is short and brutal, they tend to grow quickly and become sexually mature at a young age - a strategy that maximises their chances of siring the next generation. The…
neurophilosophy | July 13, 2008
Dave Bonta has found this advertisement, which appeared on the back cover of an anthology of English poetry published in 1884 by Funk & Wagnalls:
BRAIN AND NERVE FOOD
VITALIZED PHOS-PHITES
COMPOSED OF THE
Nerve-Giving Principles of the Ox-Brain and Wheat-Germ.
It restores the energy lost by Nervousness or Indigestion; relieves Lassitude and Neuralgia; refreshes the nerves tired by worry, excitement or excessive brain fatigue; strengthens a failing memory, and gives renewed vigor in all diseases of Nervous Exhaustion or Debility. It is the only PREVENTIVE OF CONSUMPTION.
It aids in…
neurophilosophy | July 9, 2008
A new study, published today in the open access journal PLoS One, provides evidence that remaining mentally active throughout life reduces the rate of age-related neurodegeneration and may therefore stave off Alzheimer's Disease and other forms of dementia.
Valenzuela et al used the Lifetime of Experiences Questionnaire (LEQ) to estimate the extent to which 37 healthy older individuals had engaged in complex mental activity throughout their lives. They also performed functional magnetic resonance imaging (fMRI) to measure hippocampal volume in the participants, at the beginning of the study…
edyong | July 7, 2008New parents are often extremely picky about where they live, seeking the right combination of spacious housing, local schools, and safe neighbourhoods for their tiny sprogs. A mother mosquito is no less choosy but unlike the white-picket-fence ideal of middle-class humans, she prefers areas of stagnant water, including artificial ones like rain-filled buckets or clogged drains.
But she's not looking for just any old bucket of sluggish water. A new study reveals that a pregnant Aedes aegypti mosquito seeks out just the right patch by tasting for chemicals given off by bacteria in the water.…
neurophilosophy | July 4, 2008
The Kaibo Zonshinzu is a beautiful collection of 83 anatomical illustrations on two scrolls, by a doctor named Yasukazu Minagaki from the Kyoto area. Painted in 1819, they are based on the observations he made during his dissections of more than 40 executed criminals.
Minagaki adopted the style of illustrators such as Johann Adam Kulmus. His drawings were seen by Philipp von Siebold, the Dutch anatomist who is believed to have been the first European to teach Western medicine in Japan; he was so impressed by them that he made a complimentary inscription on the first scroll.
The…
neurophilosophy | July 4, 2008Foreign accent syndrome (FAS) is a neurological condition that is acquired following a stroke or some other form of brain injury. It occurs as a result of damage to the brain's speech motor centres, so that syllables are mispronounced, making one sound as if they are speaking their native language in a foreign accent.
FAS is extremely rare, with only around 50 reported cases since 1941. Two of these were reported in stroke victims in recent years: Linda Walker, a 62-year-old woman from Newcastle, began speaking in an accent that was described as a mixture of Jamaican, Canadian and Slovakian,…
edyong | July 4, 2008
There can be few events more devastating for a parent than cot death - the sudden and unexpected death of a baby. Cot death is more formally known as Sudden Infant Death Syndrome (SIDS) and it is an apt title, for affected babies often seem outwardly healthy and show no signs of suffering. Studies have suggested that things like passive smoke and breastfeeding can affect the risk of SIDS but the underlying biology behind the syndrome is a mystery, as is the cause of death in most cases.
But it's a mystery that's slowly being solved. The latest and most intriguing clue comes from Enrica…
neurophilosophy | July 2, 2008During a cerebrovascular accident (or stroke), the blood supply to part of the brain is interrupted. This is often caused by a blood clot which blocks an artery that carries blood to the brain. Consequently, neurons in the affected region of the brain die because they are deprived of oxygen.
Stroke has several characteristic symptoms: slurred speech, paralysis and weakness on the right side of the body, and weakness and drooping of the face. These typically develop within minutes, and occur because stroke often affects the motor cortex in the left hemisphere, which controls the movements of…
neurophilosophy | July 2, 2008I was recently contacted by Heather Perry, one of the few people in the world who has performed self-trepanation.
Ms. Perry has kindly agreed to let me interview her, so I'll be traveling to Gloucestershire later this month to meet her, ask her some questions about the experience, and perhaps take a few photographs.
If you have a serious question you'd like me to ask Ms. Perry, please submit it in the comments below. I'll post the interview here at some time in the near future.
neurophilosophy | June 30, 2008We are being constantly bombarded with news stories containing pretty pictures of the brain, with headings such as "Brain's adventure centre located". Journalists now seem to refer routinely to functional magnetic resonance imaging (fMRI) as "mind reading", and exaggerated claims about its powers abound, as do misleading, irresponsible and downright ridiculous stories about the technology.
Take, for example, this article by Jeffrey Goldberg in The New Atlantic:
The preliminary findings began to arrive a few days later, in a series of e-mails..."Carter: big amygdala response on both sides…
edyong | June 28, 2008
In the final months of 2001, five people died because they opened their mail. The killers were hidden inside the envelopes, small spores that were inhaled by the unfortunate addresses. Inside their bodies, the spores turned into the deadly bacteria, Bacillus anthracis - anthrax.
Anthrax has a long history in biological warfare but it made its debut as an agent of bioterror in 2001. The US anthrax postal attacks infected 22 people and claimed the lives of five. Since then, scientists have been feverishly studying the bacteria responsible in the hope that better understanding will lead…
neurophilosophy | June 24, 2008The forthcoming issue of The New Yorker contains a fantastic article by surgeon and writer Atul Gawande about the neurobiology of itching.
The article begins with the extraordinary case of a patient known as M., whose itch, which occurred following an episode of shingles, became so unbearable that one morning she awoke to find that she had scratched through her skull and into her brain while she slept.
Gawande continues with a brief history of theories about itching - it was long considered to be a mild form of pain, but came to be recognized as a distinct sensation, following experimental…
edyong | June 21, 2008
The world's nations are stockpiling two drugs, Tamiflu and Relenza, to counter the threat of a bird flu pandemic. These drugs work by blocking a key protein that allows the virus to spread. But two years ago, a study revealed the structure of this protein and in doing so, shown that both Tamiflu and Relenza only work through a fortunate fluke.
The threat of bird flu is looming large in the minds of the public, scientists and politicians alike. So far, 241 people have died of the disease across 12 countries. But the real worry is that that the virus could mutate into a form that…