Brain

Changing one's diet to lose weight is often difficult. There may be physical and psychological effects from a changed diet that reduce the chances for success. With nearly 65% of the adult population currently classified as overweight or obese and with calorically dense foods high in fat and carbohydrates readily available, investigating those factors that contribute to dieting failures is an important effort.

Researchers found that mice withdrawn from high-fat or high-carbohydrates diets became anxious and showed changes in their brains indicating higher stress levels.

Marvin Chun of Yale University and colleagues have pinpointed brain regions critical to one of the brain’s more remarkable feats — piecing together a continuous view of the world by integrating snippets of visual input from constantly moving eyes.

Since the eyeball has only a narrow field of clear view, it must continually make tiny shifts to sample the visual world. And during these shifts, which last thousandths of a second, people are essentially blind.

Researchers have discovered that the genetic malfunction that causes a form of mental retardation called Noonan Syndrome (NS) produces an imbalance in the genesis of two types of cells in the developing embryonic brain. This imbalance, they theorize, could explain how the genetic abnormality gives rise to the neural pathology of the disorder. More broadly, they said, the new insight into the mechanism underlying NS could apply to other inherited forms of retardation.

A type of omega-3 fatty acid may slow the growth of two brain lesions that are hallmarks of Alzheimer’s disease, UC Irvine scientists have discovered. The finding suggests that diets rich in docosahexaenoic acid (DHA) can help prevent the development of Alzheimer’s disease later in life.

Cells constantly swap cargo bound in vesicles, miniscule membrane-enclosed packages of proteins and other chemicals. Before the swap can take place, the vesicle membrane must fuse with another membrane, creating channels packages can pass through.

This process, known as membrane fusion, is fundamental to health and disease. It occurs at fertilization and is particularly critical to keep hormones circulating and brain cells firing. Membrane fusion is also how HIV and other viruses infect cells.

Whiskers provide a mouse with essential information to negotiate a burrow or detect movement that could signal a predator's presence. These stiff hairs relay sensory input to the brain, which shapes neuronal activity. In a first, studies of this system by Carnegie Mellon scientists show just how well a mouse brain can compensate when limited to sensing the world through one whisker. Published April 4 in the Journal of Neuroscience, the results should help shape future studies of sensory deprivation that results from stroke or traumatic brain injury, say the authors.

People who develop dementia or Alzheimer's disease experience brain structure changes years before any signs of memory loss begin, according to a study published in the April 17, 2007, issue of Neurology®, the scientific journal of the American Academy of Neurology. Researchers say these findings may help identify people at risk of developing mild cognitive impairment (MCI), which leads to Alzheimer's disease.

Researchers have discovered how a defect in a single master gene disrupts the process by which several genes interact to create myelin, a fatty coating that covers nerve cells and increases the speed and reliability of their electrical signals.

A vaccine for treating a recurrent cancer of the central nervous system that occurs primarily in the brain has shown promise in preliminary data from a clinical trial at the University of California, San Francisco.

Dream journals being kept by students in a college psychology class have provided researchers with a unique look at how people experienced the events of 9/11, including the influence that television coverage of the World Trade Center attacks had on people’s levels of stress.