Inner-ear disorders may cause hyperactivity

http://www.eurekalert.org/pub_releases/2013-09/aeco-idm090413.php

Public release date: 5-Sep-2013
Contact: Kim Newman
Albert Einstein College of Medicine

September 5, 2013 — (Bronx, NY) — Behavioral abnormalities are traditionally thought to originate in the brain. But a new study by researchers at Albert Einstein College of Medicine of Yeshiva University has found that inner-ear dysfunction can directly cause neurological changes that increase hyperactivity. The study, conducted in mice, also implicated two brain proteins in this process, providing potential targets for intervention. The findings were published today in the online edition of Science.

For years, scientists have observed that many children and adolescents with severe inner-ear disorders – particularly disorders affecting both hearing and balance – also have behavioral problems, such as hyperactivity. Until now, no one has been able to determine whether the ear disorders and behavioral problems are actually linked.

"Our study provides the first evidence that a sensory impairment, such as inner-ear dysfunction, can induce specific molecular changes in the brain that cause maladaptive behaviors traditionally considered to originate exclusively in the brain," said study leader Jean M. Hébert, Ph.D., professor in the Dominick P. Purpura Department of Neuroscience and of genetics at Einstein.

-----

"Our study also raises the intriguing possibility that other sensory impairments not associated with inner-ear defects could cause or contribute to psychiatric or motor disorders that are now considered exclusively of cerebral origin," said Dr. Hébert. "This is an area that has not been well studied."