NIMH, the National Institute of Mental Health, is a subunit of the United States National Institutes of Health (NIH). NIMH operates a Web site at, according to which, "The mission of the National Institute of Mental Health (NIMH) is to diminish the burden of mental illness through research."

Whether or not NIMH scientists ever engaged in experiments to boost the intelligence of rats I do not know ... but many people seem to have first heard of NIMH through Robert C. O'Brien's semi-science-fiction book, Mrs. Frisby and the Rats of NIMH.