9319927 Satterlie Behavioral arousal in animals and humans occurs when there is a change in several independent behaviors so that the overall behavioral output is more focussed or efficient. Behavioral arousal is an important issue that is not well-understood at the cellular level. In the marine mollusc Clione when prey is nearby, a feeding arousal response occurs in which there is a decreased threshold for starting the feeding behavior, an increase in swimming speed for more efficient prey capture, an increase in heart rate and an inhibition of the withdrawal response. This work will investigate the cellular mechanisms in the nervous system that give rise to this change in behavioral state and examine the role of the brain chemical serotonin in this behavior. Clione is an excellent animal in which to study behavioral arousal because the neural circuits that underlie the component behaviors (feeding, swimming, and withdrawal) have already been worked out and the level of individual nerve cells by the PI and others. The PI has also shown that injection of serotonin into the animal results in feeding arousal behavior and that there are cells in the Clione nervous system that contain serotonin. ***
