The effects of acute stress exposure on striatal activity during Pavlovian conditioning with monetary gains and losses

Abstract

Pavlovian conditioning involves the association of an inherently neutral stimulus with an appetitive or aversive outcome, such that the neutral stimulus itself acquires reinforcing properties. Across species, this type of learning has been shown to involve subcortical brain regions such as the striatum and the amygdala. It is less clear, however, how the neural circuitry involved in the acquisition of Pavlovian contingencies in humans, particularly in the striatum, is affected by acute stress. In the current study, we investigate the effect of acute stress exposure on Pavlovian conditioning using monetary reinforcers. Participants underwent a partial reinforcement conditioning procedure in which neutral stimuli were paired with high and low magnitude monetary gains and losses. A between-subjects design was used, such that half of the participants were exposed to cold stress while the remaining participants were exposed to a no stress control procedure. Cortisol measurements and subjective ratings were used as measures of stress. We observed an interaction between stress, valence, and magnitude in the ventral striatum, with the peak in the putamen. More specifically, the stress group exhibited an increased sensitivity to magnitude in the gain domain. This effect was driven by those participants who experienced a larger increase in circulating cortisol levels in response to the stress manipulation. Taken together, these results suggest that acute stress can lead to individual differences in circulating cortisol levels which influence the striatum during Pavlovian conditioning with monetary reinforcers.

Acute Stress Impairs Self-Control in Goal-Directed Choice by Altering Multiple Functional Connections within the Brain’s Decision Circuits

“…When viewing cues or anticipating monetary outcomes, stressed individuals show greater activity in reward regions including the amygdala, striatum, and medial prefrontal cortex (Dagher et al, 2009;Kumar et al, 2014), and acute psychosocial stress may increase dopamine levels in the vStr (Pruessner et al, 2004). Stress also alters risk preferences during monetary gambles in humans (Putman et al, 2010;Starcke et al, 2008;van den Bos et al, 2009), and it can change the perception and influence of reward at the time of consumption (Lewis et al, 2014;Porcelli et al, 2012;Preston et al, 2007;Putman et al, 2010;Schwabe et al, 2012;Schwabe and Wolf, 2010;Starcke and Brand, 2012). Moreover, stress has been associated with aggravating addiction processes (Ansell et al, 2012;Koob and Le Moal, 2008).…”

“…In reality, however, many important decisions are made during or immediately following stressful events that occur regularly in daily life (Smyth et al, 1998). Experimental data demonstrate that stress can have both immediate and long-lasting effects on brain and behavior (Duckworth et al, 2012;Kandasamy et al, 2014;Lewis et al, 2014;McEwen and Morrison, 2013;Schwabe and Wolf, 2010). Even relatively moderate and acute stressors have been shown to affect decision-making (Gathmann et al, 2014;Lempert et al, 2012;Porcelli and Delgado, 2009;Porcelli et al, 2012;Schwabe et al, 2012;Schwabe and Wolf, 2009;Starcke et al, 2008).…”

Stress increases cue-triggered “wanting” for sweet reward in humans.

“…Although the present finding provides evidence showing that stress increases cue-triggered wanting and not self-reported liking, the mechanism underlying this phenomenon remains to be explored. Recent evidence from animal (Cabib & Puglisi-Allegra, 2012) and human (e.g., Lewis, Porcelli, & Delgado, 2014) literature suggests that stress increases the dopaminergic activity in the ventral striatum. According to the incentive salience theory, the dopaminergic activity in this region is selectively involved in wanting (and not in liking; Berridge & Robinson, 2003); therefore, one could speculate that stress directly and selectively activate the mesolimbic brain network involved in wanting.…”

The psychology of intelligence analysis: Drivers of prediction accuracy in world politics.

“…Recent evidence from animal (Cabib & Puglisi-Allegra, 2012) and human (e.g., Lewis, Porcelli, & Delgado, 2014) literature suggests that stress increases the dopaminergic activity in the ventral striatum. According to the incentive salience theory, the dopaminergic activity in this region is selectively involved in wanting (and not in liking; Berridge & Robinson, 2003); therefore, one could speculate that stress directly and selectively activate the mesolimbic brain network involved in wanting.…”