Dopaminergic and serotonergic modulation of anterior insular and orbitofrontal cortex function in risky decision making

• Published in: Neuroscience research 2015-03, Vol.92, p.53-61
• Main Authors: Ishii, Hironori, Ohara, Shinya, Tobler, Philippe N., Tsutsui, Ken-Ichiro, Iijima, Toshio
• Format: Article
• Language: English
• Subjects: Animals; Cerebral Cortex - drug effects; Cerebral Cortex - physiology; Decision Making - drug effects; Decision Making - physiology; Dopamine Antagonists - pharmacology; Dopamine D2 Receptor Antagonists; Gambling; Male; Prefrontal Cortex - drug effects; Prefrontal Cortex - physiology; Rat; Rats; Rats, Wistar; Receptors, Dopamine D1 - antagonists & inhibitors; Reward; Risk; Risk-based decision making; Serotonin 5-HT1 Receptor Antagonists; Serotonin 5-HT2 Receptor Antagonists; Serotonin Antagonists - pharmacology
• ISSN: 0168-0102; 1872-8111
• DOI: 10.1016/j.neures.2014.11.009

•We investigated DA and 5-HT modulation of AIC and OFC function in risky choice.•Blocking 5-HT1AR in OFC decreased risk preference.•AIC D2R and 5-HT1AR had different outcome history-dependent effects on risky choice.•Blocking D2R in AIC increased risk preference particularly after winning gambles.•Blocking 5-HT1AR in AIC increased risk preference particularly after losing gambles. Systemic manipulations have shown that dopamine and serotonin systems are involved in risky decision making. However, how they work within the regions that implement risky choices remains unclear. The present study investigated the role of dopamine and serotonin in the rat anterior insular cortex (AIC) and orbitofrontal cortex (OFC), which make different contributions to risky decision making. We examined the effects of local injection of the D1 (SCH23390), D2 (eticlopride), 5-HT1A (WAY100635) and 5-HT2A (M100907) receptor antagonists into the AIC or OFC on risk preference in a gambling task. We found that different dopamine and serotonin receptor subtypes in the AIC and OFC differentially influence risky decision making: intra-AIC injection of D2R or 5-HT1AR blockers increased risk preference whereas intra-OFC injection of the 5-HT1AR blocker decreased it. Risk preference was not altered by intra-AIC injection of D1R and 5-HT2AR blockers or by intra-OFC injection of D1R, D2R, and 5-HT2AR blockers. Furthermore, additional analyses revealed that dopamine and serotonin signaling in the AIC have outcome history-dependent effects on risk taking: intra-AIC injection of the D2R blocker increased risk preference particularly after winning in a previous risky choice, whereas intra-AIC injection of the 5-HT1AR blocker increased risk preference after losing.