RT Journal Article SR Electronic T1 Convergent Mechanisms Mediate Preparatory States and Repetition Priming in the Feeding Network of Aplysia JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 4029 OP 4033 DO 10.1523/JNEUROSCI.23-10-04029.2003 VO 23 IS 10 A1 Proekt, Alex A1 Weiss, Klaudiusz R. YR 2003 UL http://www.jneurosci.org/content/23/10/4029.abstract AB Improvement of behavioral responses to expected stimuli has been attributed to a change in the preparatory state. In this study, we take advantage of the accessibility of the nervous system of Aplysia and develop an in vitro analog of the preparatory state for feeding behaviors. We provide evidence that the change in the preparatory state may be elicited initially by activity of identified serotonergic metacerebral cells (MCCs). We demonstrate, however, that the preparatory state is maintained through MCC-independent repetition priming that is embedded in the properties of the behavior-generating network. Both MCC-dependent and MCC-independent processes converge on the same site in the behavior-generating network to mediate the change in the preparatory state. Thus, we propose a model of how multiple neuronal structures interact to elicit and maintain changes in the preparatory states in the CNS.