Meeting Abstract
Catecholamines (CAs) are a conserved group of neurochemicals (including dopamine and noradrenaline) that are well-established modulators of neural circuits associated with various motivated sociosexual behaviors, including intraspecific vocal communication. The plainfin midshipman fish, Porichthys notatus, is an exceptional model for investigating mechanisms underlying vertebrate vocal behavior because production and recognition of social acoustic signals is crucial to their reproductive success. There are two male sexual phenotypes with corresponding alternative mating strategies: type I males court females into nests with advertisement calls or “hums” while type II males sneak spawn in competition with larger type Is. While CA circuitry may help assess the salience of social acoustic stimuli, it is unknown whether specific CA nuclei respond differently to attractive (hum) versus unattractive (grunt) calls. We tested the hypothesis that various CA nuclei would be differentially responsive to divergent social-acoustic signals in type II males. Sneaker males were exposed to playbacks of field recorded advertisement hums, agonistic grunts, or ambient noise. cFos (an immediate early gene product that is a proxy for neural activation) was quantified within CA nuclei by double labeling with tyrosine hydroxylase, the rate-limiting enzyme in CA synthesis. Results show activity in two populations of forebrain dopamine neurons were higher when exposed to hums than compared to ambient noise, suggesting that hums preferentially activate these nuclei. These data support specific CA nuclei as modulators of social acoustic driven behaviors.
