S6-2.3  Saturday, Jan. 5  Social Regulation of the Brain FERNALD, R.D.; Stanford University

How does behavior change the brain? The long term objective our research program is to understand how social interactions produce specific changes in the brain. While it is common to study how the brain controls behavior, learning how the brain is influenced by behavior offers uncommon challenges. To do this, we study the social control of reproduction which is arguably the most important event in an animal’s life. To understand how behavior influences the reproductive control axis we study a teleost fish model system that provides unusual opportunities for understanding plasticity in the vertebrate nervous system. Changes in social status of an individual male causes a reversible change in the size of an identified group of gonadotropin releasing hormone containing neurons and their connections in the brain. Moreover, status change regulates receptor expression of key reproductive hormones as well as changing expression of key genes. These studies provide new insights into mechanisms through which social encounters influence cellular and molecular processes necessary for subsequent behavior.