Orio Alvarez, Patricio (Director de tesis)Piñeiro Feick, Miguel2022-07-212022-07-212018-05Piñeiro Feick, M. (2018). Study of the role of CCAP neurons of the ecdysial behavorial sequence through mathematical and computational methods (tesis de postgrado). Universidad de Valparaíso, Valparaíso, Chilehttp://repositoriobibliotecas.uv.cl/handle/uvscl/4623Animal behavior arises from the interplay between neural, biomechanical and environmental dynam- ics. Neuromodulators, such as neuropeptides can regulate and reconfigure neural circuits to alter their output, affecting in this way animal behavior. How neuromodulators act on neural circuits to produce distinct behaviors is still poorly understood. Here I studied the peptidergic circuits that orchestrates the ecdysis behavioral sequence in Drosophila. This behavioral sequence has three phases: pre-ecdysis, ecdysis and post-ecdysis. The sequence is initiated by the release of ecdysis-triggering hormone (ETH) which activates multiple neuronal targets of which crustacean cardioactive peptide (CCAP) neurons have been identified as key for the successful execution of the behavioral sequence. How CCAP neu- rons regulate the behavioral sequence is still not clear, but studies of Manduca have showed that CCAP can initiate the ecdysial motor activity. I used calcium imaging data (from CCAP neurons only, and from CCAP neurons together with motoneurons), behavioral data from pupal ecdysis, and mathematical and computational approaches to study the dynamics and functional connectivity between CCAP neurons and motoneurons, and how they relate to the behavior. I found that CCAP neurons tightly regulate the motoneuronal activity during the ecdysis and post-ecdysis phases, consistent with the recent identifica- tion of CCAP targets. The behavioral analysis showed that while the three major phases of the ecdisis sequence can be detected in the motoneuronal recordings, motoneurons have major differences in the timing and regularity of their activity. Moreover, I found that the post-ecdysis phase has two subphases which appear to be absent in the motoneuronal recordings. These results give us new insights into the peptidergic regulation of motor programs and behaviors.enNEUROCIENCIAS COMPUTACIONALMETODOS ESTADISTICOSCONDUCTA ANIMALTesis