The hippocampus is believed to be the brain’s primary learning and memory center and plays critical roles in processing, storing, and recalling information. This seahorse-shaped structure is highly susceptible to damage through stroke or lack of oxygen and is thought to be critically involved in Alzheimer’s disease. Life scientists from UCLA and Australia have now identified regions of the brain that are able to create alternate pathways to help compensate for the lost neural function. These complex new neural circuits are often far from the damaged hippocampus site. In rat-brain studies, parts of the prefrontal cortex were seen to take over when the hippocampus was disabled. Areas in the prefrontal cortex compensated in different ways, with one sub-region (infralimbic cortex) silencing its activity and another sub-region (prelimbic cortex) increasing its activity. This is the first demonstration of such neural-circuit plasticity and could potentially help scientists develop new treatments for Alzheimer’s disease, stroke, and other conditions involving damage to the brain.
Friday, May 24, 2013
Complex behavior always involves multiple parts of the brain communicating with one another, with one region’s message affecting how another region will respond. Fortunately, the brain is heavily interconnected. Researchers say you can get from any neuron in the brain to any other neuron in about six synaptic connections. Classically, specific brain circuits have been linked to dedicated types of brain functions. Recent research by UCLA’s Michael Fanslow and Moriel Zelikowsky in collaboration with Bryce Vissel at Sydney Australia’s Garvan Institue of Medical Research has revealed some fascinating and encouraging results about the ability of the brain to develop alternate brain function connections. Studies of rat brains with damage in the hippocampus revealed that the brain was able to recruit alternate circuits that allowed the brain to compensate for some of the damage. This is exciting as it offers promise for targeted treatment of memory disorders. More tomorrow . . .
Thursday, May 23, 2013
Did you hear the news item reporting that a famous actor apparently is convinced that he suffers from face blindness or prosopagnosia, (from the Greek prosopon for face and agnosia for ignorance)? it’s not that the individuals are unable to recognize a human face, it’s that they have difficulty recognizing the same set of features when they see them again. For a good many years prosopagnosia was believed to be very rare and stem from some type of brain injury. That impression has changed based on studies by a team of German researchers. Their conclusions, published in the American Journal of Medical Genetics, showed that this is a highly heritable condition (e.g., they speculate it may be caused by a defect in a single dominant gene). It is more common than previously believed, estimated to affect about 1 in 50 people. Of course the condition varies widely: some individuals are able to memorize a limited number of faces, while others have difficulty recognizing their own face in group pictures. Most prosopagnosics learn to cope early on by training themselves to distinguish people based on cues like hairstyle, voice, gait, or body shape; or avoiding places where they could unexpectedly run into someone they know; or pretending to be lost in thought (unfortunately giving rise to the assumption that they are “stuck up”); or acting friendly to everyone; and so on. While I typically have some sense about whether or not I’ve seen a specific face before, I rarely know WHERE that was. My modus operandi is simply to say, “I believe we’ve met before. Please remind be when and where.” Knowing about prosopagnosia and its estimated prevalence gives you the option of not taking it personally when it appears someone has failed to recognize you . . .
Wednesday, May 22, 2013
Have you paid attention to the names that have been given to offspring of the "famous," so called? If you are born in the United States, chances are good that your parents may give you any names they want—no matter how bizarre they may seem to others. If you are born in some other country, maybe not. New Zealand reportedly released an updated list of 77 unacceptable baby names (e.g., Royal, Duke, Major, Bishop, Majesty, J, Lucifer, Knight, Lady, Judge, Royale, Messiah, T, I, Queen, II, Sir, III, Jr, E, V, Justus, Master, Constable, Queen Victoria, Regal, Emperor, Christ, Justice, 3rd, C J, G, Roman numerals III, General, Saint, Lord, . [full stop], 89, Eminence, M, VI, Mafia No Fear, 2nd, Majesti, Rogue, 4real, * [star symbol], 5th, S P, C, Sargent, Honour, D, Minister, MJ, Chief, Mr, V8, President, MC, Anal, A.J, Baron, L B, H-Q, Queen V). And New Zealand isn’t the only country taking an interest in names foisted on babies. In Germany, the baby’s names must clearly indicate gender. And in Iceland, if the names are not already on the National Register of Persons, the parents must submit an application, which will be reviewed by a federal committee that ultimately rules on the application, addressing grammatical concerns along with potential effects the name will have on the child later on. In Sweden, first names are not to cause offense or discomfort for the one using it. (Mentalfloss.com has some interesting commentary.)
Tuesday, May 21, 2013
Making a fist may help prevent performance choking but is there any evidence it can help with memory? The result of a study led by Ruth Propper of Montclair State University in New Jersey and published in the journal PLoS One, suggest that some simple body movements can improve memory by temporarily changing the way the brain functions. Clenching your right fist before remembering information and your left when you want to remember it can boost your recall. This strange strategy may work because clenching your hands activates the side of the brain that handles the function. In right-handed people, for example, the left side of the brain is primarily responsible for encoding information, while the right hemisphere is primarily responsible for recalling memory. (If you are left-handed, the opposite may apply but this is as yet unclear.) Propper and colleagues studied 50 right-handed college students, mainly women. They were given a list of 36 words to remember and a small pink ball to clench. One group squeezed the ball twice for 45 seconds each time with their right hands before memorizing the words, then did the same with their left hands before writing down as many words as they could recall. Another group performed the same task but reversed the order of the fists they made. The group that started with the right hand and activated the left hemisphere, which helps encode memory, and then clenched their left hand and activated the right hemisphere during recall, performed the best on the memory test. They recalled an average of 10 words if they clenched their right hand for encoding and left for recall, which was four more than those who used the opposite clenching pattern. You might want to experiment with this . . .
Monday, May 20, 2013
No surprise, neuroscientists are looking for ways to help individuals avoid the phenomenon of choking. According to new research published by the American Psychological Association, some athletes may improve their performance under pressure by using a simple technique to activate specific parts of the brain. For example, by squeezing a ball or clenching their left hand before competition. Because of lateral specialization of the two hemispheres, researchers theorized that squeezing a ball or clenching the left hand would activate the right hemisphere of the brain and reduce the likelihood of an athlete’s choking under pressure. In three experiments with experienced soccer players, judo experts and badminton players, researchers in Germany tested the athletes’ skills during practice and then in stressful competitions before a large crowd or video camera. Right-handed athletes who squeezed a ball in their left hand before competing were less likely to choke under pressure than right-handed players who squeezed a ball in their right hand. (Studies have focused exclusively on right-handed athletes because some relationships between different parts of the brain aren’t as well understood for left-handed people, according to the authors. (Note: while this technique probably wouldn’t help athletes whose performance is based on strength or stamina, such as weightlifters or marathon runners, it could apply to athletes whose performance is based on accuracy and complex body movements, such as soccer players or golfers.) This research could have important implications outside athletics, as well. For example, elderly people who are afraid of falling often focus too much on their movements, so right-handed elderly people may be able to improve their balance by clenching their left hand before walking or climbing stairs.
Sunday, May 19, 2013
Rumination can interfere with concentration and performance of motor tasks, resulting in the phenomenon of choking. Athletes usually perform better when they trust their bodies rather than thinking too much about their own actions or what their coaches told them during practice, at least according to researcher Juergen Beckmann PhD, chair of sport psychology, Technical University of Munich in Germany. Something as simple as consciously trying to keep one’s balance, for example, may produce imbalance, as was seen in some sub-par performances by gymnasts during the Olympics in London. Research has shown that rumination is associated with the brain’s left hemisphere. It’s the right hemisphere that is associated with superior performance in automated behaviors, such as those used by some athletes. The right hemisphere controls movements of the left side of the body, and the left hemisphere controls the right side. Too much “rumination,” therefore, appears to activate the left hemisphere, which may result in choking. Researchers have been attempting to find ways to activate the right hemisphere and capitalize on the brain’s automated behaviors. More on that tomorrow.