Human Gene Affects Memory
NIH scientists have shown that a common gene variant influences memory for events in humans by altering a growth factor in the brain’s memory hub. On average, people with a particular version of the gene that codes for brain derived neurotrophic factor (BDNF) performed worse on tests of episodic memory ? tasks like recalling what happened yesterday. They also showed differences in activation of the hippocampus, a brain area known to mediate memory, and signs of decreased neuronal health and interconnections. These effects are likely traceable to limited movement and secretion of BDNF within cells, according to the study, which reveals how a gene affects the normal range of human memory, and confirms that BDNF affects human hippocampal function much as it does animals’.
Researchers funded by the National Institute of Mental Health (NIMH) have discovered a high tech way to quell panic in rats. They have detected the brain’s equivalent of an “all clear” signal, that, when simulated, turns off fear. The discovery could lead to non-drug, physiological treatments for runaway fear responses seen in anxiety disorders. Rats normally freeze with fear when they hear a tone they have been conditioned to associate with an electric shock. Dr. Gregory Quirk and Mohammed Milad, Ponce School of Medicine, Puerto Rico, have now demonstrated that stimulating a site in the front part of the brain, the prefrontal cortex, extinguishes this fear response by mimicking the brain’s own “safety signal.”
A new study aims to determine once and for all whether a link exists between obsessive-compulsive behavior and strep infections in children. The research, to be conducted by the University of Florida and the National Institutes of Mental Health, is prompted by anecdotal reports from parents with OCD kids that their children’s behavior, such as compulsive hand washing, worsens when the child is ill with strep.