Rare mutations that increase the risk of neuro-psychiatric diseases usually occur in only one copy of a gene. What happens when both copies are mutated?

Lithium treatment reverses some of the behavioral and brain-cell abnormalities in mouse models of fragile X syndrome ― an inherited form of mental retardation that includes learning deficits, aggressiveness, and social withdrawal ― according to research presented today at the Society for Neuroscience meeting.

For parents of children with autism, bedtime can be a boondoggle.