Open AccessStriatal responsiveness to reward under threat‐of‐shock and working memory load: A preliminary study
Author(s) -
Gaillard Claudie,
Guillod Matthias,
Ernst Monique,
Torrisi Salvatore,
Federspiel Andrea,
Schoebi Dominik,
Recabarren Romina E.,
Ouyang Xinyi,
MuellerPfeiffer Christoph,
Horsch Antje,
Homan Philipp,
Wiest Roland,
Hasler Gregor,
MartinSoelch Chantal
Publication year - 2019
Publication title -
brain and behavior
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.915
H-Index - 41
ISSN - 2162-3279
DOI - 10.1002/brb3.1397
Subject(s) - putamen , psychology , nucleus accumbens , anticipation (artificial intelligence) , neuroscience , ventral striatum , cognition , functional magnetic resonance imaging , reward system , working memory , effects of sleep deprivation on cognitive performance , stressor , arousal , striatum , caudate nucleus , central nervous system , dopamine , artificial intelligence , computer science
Reward and stress are important determinants of motivated behaviors. Striatal regions play a crucial role in both motivation and hedonic processes. So far, little is known on how cognitive effort interacts with stress to modulate reward processes. This study examines how cognitive effort (load) interacts with an unpredictable acute stressor (threat‐of‐shock) to modulate motivational and hedonic processes in healthy adults. Materials and Methods A reward task, involving stress with unpredictable mild electric shocks, was conducted in 23 healthy adults aged 20–37 (mean age: 24.7 ± 0.9; 14 females) during functional magnetic resonance imaging (fMRI). Manipulation included the use of (a) monetary reward for reinforcement, (b) threat‐of‐shock as the stressor, and (c) a spatial working memory task with two levels of difficulty (low and high load) for cognitive load. Reward‐related activation was investigated in a priori three regions of interest, the nucleus accumbens (NAcc), caudate nucleus, and putamen. Results During anticipation, threat‐of‐shock or cognitive load did not affect striatal responsiveness to reward. Anticipated reward increased activation in the ventral and dorsal striatum. During feedback delivery, both threat‐of‐shock and cognitive effort modulated striatal activation. Higher working memory load blunted NAcc responsiveness to reward delivery, while stress strengthened caudate nucleus reactivity regardless reinforcement or load. Conclusions These findings provide initial evidence that both stress and cognitive load modulate striatal responsiveness during feedback delivery but not during anticipation in healthy adults. Of clinical importance, sustained stress exposure might go along with dysregulated arousal, increasing therefore the risk for the development of maladaptive incentive‐triggered motivation. This study brings new insight that might help to build a framework to understand common stress‐related disorders, given that these psychiatric disorders involve disturbances of the reward system, cognitive deficits, and abnormal stress reactivity.