Neuroscience

Orientation is a puzzle to neuroscience researchers and ever more puzzling to us.   If you've ever been lost, or even just in a strange place, you know the feeling of mild panic.  But once you get your bearings, that feeling goes away.    Disorientation is unpleasant but our brain quickly sorts it out.  Some researcher suggests that animals and young children mainly rely on geometric cues (e.g. lengths, distances, angles) to help them get reoriented while adults can also make use of feature cues (e.g. color, texture, landmarks) in the surrounding area. Your brain has…

6 newly discovered genes for obesity have a neural effect, according to the international GIANT (Genetic Investigation of Anthropometric Parameters) consortium. So far, the scientists have analyzed two million DNA variations in 15 genome-wide association studies with a total of more than 32,000 participants and the identified candidate genes were validated in 14 further studies including 59,000 participants. In addition to the FTO and MC4R genes already known, it was now possible for six more obesity genes to be identified: TMEM18, KCTD15, GNPDA2, SH2B1, MTCH2, and NEGR1. Gene expression…

New cells are born every day in the brain's hippocampus, but what controls this birth has remained a mystery. Reporting in Science, neuroscientists at the Johns Hopkins University School of Medicine have discovered that the birth of new cells depends on a protein that is involved in changing epigenetic marks in the cell's genetic material.  "How is it that when you see someone you met ten years ago, you still recognize them? How do these transient events become long lasting in the brain, and what potential role does the birth of new neurons play in making these memories?" says Hongjun…

Attention Deficit/Hyperactivity Disorder (ADHD) is a complex condition considered by some to have both environmental and genetic causes. It is characterized by developmentally inappropriate levels of inattention, hyperactivity and impulsivity that has an onset in childhood. It has become one of the most commonly diagnosed psychiatric diseases, diagnosed in up to 8 percent of children worldwide. The drugs used to treat ADHD are effective, making ADHD one of the most treatable psychiatric disorders. but these treatments are not curative and leave patients with residual disability. Because ADHD…

Obstructive sleep apnea decreases blood flow to the brain, elevates blood pressure within the brain and eventually harms the brain's ability to modulate these changes and prevent damage to itself, according to a new study published by The American Physiological Society. The findings may help explain why people with sleep apnea are more likely to suffer strokes and to die in their sleep. Sleep apnea is the most commonly diagnosed condition amongst sleep-related breathing disorders and can lead to debilitating and sometimes fatal consequences for the 18 million Americans who have been…

Women with bulimia nervosa appear to respond more impulsively during psychological testing than those without eating disorders, and brain scans show differences in areas responsible for regulating behavior, according to a report in the January issue of Archives of General Psychiatry. Bulimia nervosa often begins in the adolescent or young adult years, according to background information in the article. "Primarily affecting girls and women, it is characterized by recurrent episodes of binge eating followed by self-induced vomiting or another compensatory behavior to avoid weight gain," the…

People with a sleep disorder that causes them to kick or cry out during their sleep may be at greater risk of developing dementia or Parkinson’s disease, according to a study published in Neurology.  The sleep disorder is called REM sleep behavior disorder. People with the disorder do not have the normal lack of muscle tone that occurs during REM sleep, often known as the dream stage of sleep. Instead, they have excessive muscle activity such as punching, kicking, or crying out, essentially acting out their dreams.  The study involved 93 people with this type of sleep disorder who…

Group exercise programs, treadmill training and horseback riding can be healthy choices for children with developmental disabilities, a new review of studies concludes.  With these kinds of activities, children with disorders such as autism, mental retardation and cerebral palsy can improve their coordination and aerobic fitness, according to research analyzed by Connie Johnson, PT, a physical therapist with the Fairfax County Public Schools in Virginia. The findings are encouraging, since studies show that children with developmental disabilities tend to be less fit than their peers. In…

Facial expressions of emotion are hardwired into our genes, according to a study published today in the Journal of Personality and Social Psychology. The research suggests that facial expressions of emotion are innate rather than a product of cultural learning. The study is the first of its kind to demonstrate that sighted and blind individuals use the same facial expressions, producing the same facial muscle movements in response to specific emotional stimuli.  The study also provides new insight into how humans manage emotional displays according to social context, suggesting that the…

During an autoimmune disease, the endogenous defence system (the immune system) loses the ability to distinguish between "self" and "foreign".     As a consequence, the immune system directs its defense against itself, with fatal consequences. In the case of multiple sclerosis, a chronic, inflammatory autoimmune disease, the immune system attacks the protective layer encapsulating the nerve fibres: This protective layer formed by myelin works like insulation for electrical cables. If the insulation is damaged, the nerves can no longer transmit messages effectively.  In the…