Format

Send to

Choose Destination
PLoS One. 2014 Jul 21;9(7):e102240. doi: 10.1371/journal.pone.0102240. eCollection 2014.

Neuromodulatory control of a goal-directed decision.

Author information

1
The Neuroscience Program, University of Illinois, Urbana, Illinois, United States of America.
2
Department of Molecular & Integrative Physiology, University of Illinois, Urbana, Illinois, United States of America.
3
Department of Molecular & Integrative Physiology, University of Illinois, Urbana, Illinois, United States of America; The Neuroscience Program, University of Illinois, Urbana, Illinois, United States of America.

Abstract

Many cost-benefit decisions reduce to simple choices between approach or avoidance (or active disregard) to salient stimuli. Physiologically, critical factors in such decisions are modulators of the homeostatic neural networks that bias decision processes from moment to moment. For the predatory sea-slug Pleurobranchaea, serotonin (5-HT) is an intrinsic modulatory promoter of general arousal and feeding. We correlated 5-HT actions on appetitive state with its effects on the approach-avoidance decision in Pleurobranchaea. 5-HT and its precursor 5-hydroxytryptophan (5-HTP) augmented general arousal state and reduced feeding thresholds in intact animals. Moreover, 5-HT switched the turn response to chemosensory stimulation from avoidance to orienting in many animals. In isolated CNSs, bath application of 5-HT both stimulated activity in the feeding motor network and switched the fictive turn response to unilateral sensory nerve stimulation from avoidance to orienting. Previously, it was shown that increasing excitation state of the feeding network reversibly switched the turn motor network response from avoidance to orienting, and that 5-HT levels vary inversely with nutritional state. A simple model posits a critical role for 5-HT in control of the turn network response by corollary output of the feeding network. In it, 5-HT acts as an intrinsic neuromodulatory factor coupled to nutritional status and regulates approach-avoidance via the excitation state of the feeding network. Thus, the neuromodulator is a key organizing element in behavioral choice of approach or avoidance through its actions in promoting appetitive state, in large part via the homeostatic feeding network.

PMID:
25048964
PMCID:
PMC4105495
DOI:
10.1371/journal.pone.0102240
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center