We are studying the role of serotonin neurons in mediating the effects of acidosis on brain function and behavior.  We have shown that serotonin neurons are exquisitely sensitive to changes in pH.  They are close to large arteries in the brain and contribute to the increase in breathing induced by increased CO2 levels (which indirectly decreases pH).  They are also essential for the arousal from sleep that is induced by high CO2. We are using a variety of transgenic mice, brain slices and tissue culture to understand the mechanisms and significance of these responses, and a variety of techniques including patch clamp recordings, whole animal behavioral studies, confocal imaging and molecular biology.  These experiments are also aimed at understanding the role of these effects in human conditions in which sudden death occurs, such as infancy (SIDS), epilepsy (SUDEP) and Parkinson's disease.