Contextual coding of aggressive signals in weakly electric fish

Abstract

Event Abstract Back to Event Contextual coding of aggressive signals in weakly electric fish Maurice Chacron1* 1 McGill University, Canada Although serotonergic pathways project unto many sensory brain areas, the consequences of such innervations on information processing are not well understood. We have previously shown that serotonin induces burst activity in pyramidal neurons of the electrosensory lateral line lobe (ELL) of weakly electric fish in vitro, which results in better detection of low frequency stimulus features. Here, to further investigate this effect under more natural conditions, we used an in vivo preparation and recorded from the same neurons in awake, behaving brown ghost fish. Extracellular and sharp electrode intracellular techniques were used to record responses of pyramidal neurons to serotonin after either focal application of serotonin to the molecular layer of ELL or electrical stimulation of raphe nuclei. Sine waves (2-256 Hz) were either applied locally to imitate prey or globally to imitate beats resulting from interaction between fish. Small chirps (i.e., aggressive signals) were produced by brief increases in the electric organ discharge frequency (EOD), whereas big chirps (i.e., courtship signals) were produced by long duration concomitant increases and decreases in EOD frequency and amplitude, respectively. In addition to an increased burst firing in ELL pyramidal neurons, serotonin application resulted in an increased phase locking of responses to low frequency (<64 Hz) sine wave stimuli. Further experiments revealed that serotonin did not alter coding of prey signal (i.e., local sinusoids). These results suggest that enhancement in phase locking during global communication is mediated by a feedback mechanism. Furthermore, serotonin application decreased the variability in timing of the first spike and improved the reliability of response to small chirp stimuli. Together, our findings indicate that serotonin, through burst generation in pyramidal neurons and modulation of a feedback pathway, improves the detection of same sex interactions through two mechanisms: increase reliability of coding of aggressive signals (i.e., small chirp) produced by dominant fish and better detection of low frequency beats generated during same sex interaction. Keywords: aggressive signals, Serotonin, weakly electric fish Conference: Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012. Presentation Type: Poster (but consider for student poster award) Topic: Neuromodulation Citation: Chacron M (2012). Contextual coding of aggressive signals in weakly electric fish. Conference Abstract: Tenth International Congress of Neuroethology. doi: 10.3389/conf.fnbeh.2012.27.00370 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 01 May 2012; Published Online: 07 Jul 2012. * Correspondence: Dr. Maurice Chacron, McGill University, Montreal, Canada, maurice.chacron@mcgill.ca Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Maurice Chacron Google Maurice Chacron Google Scholar Maurice Chacron PubMed Maurice Chacron Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.