Effects of motivation on reward and attentional networks: an fMRI study

Brain and Behavior

Iliyan Ivanov¹  Xun Liu¹  Suzanne Clerkin¹  Kurt Schulz¹  Karl Friston²  Jeffrey H. Newcorn¹ 

[1] Department of Psychiatry, Mount Sinai School of Medicine, New York, New York;Wellcome Center for Neuroimaging, University College London, London, United Kingdom

关键词: Attention;    brain reward system;    fMRI;    motivation;    neuroimaging;    neuroscience;   

DOI  :  10.1002/brb3.80

来源: Wiley

【 摘 要 】

Abstract

Existing evidence suggests that reward and attentional networks function in concert and that activation in one system influences the other in a reciprocal fashion; however, the nature of these influences remains poorly understood. We therefore developed a three-component task to assess the interaction effects of reward anticipation and conflict resolution on the behavioral performance and the activation of brain reward and attentional systems. Sixteen healthy adult volunteers aged 21–45 years were scanned with functional magnetic resonance imaging (fMRI) while performing the task. A two-way repeated measures analysis of variance (ANOVA) with cue (reward vs. non-reward) and target (congruent vs. incongruent) as within-subjects factors was used to test for main and interaction effects. Neural responses to anticipation, conflict, and reward outcomes were tested. Behaviorally there were main effects of both reward cue and target congruency on reaction time. Neuroimaging results showed that reward anticipation and expected reward outcomes activated components of the attentional networks, including the inferior parietal and occipital cortices, whereas surprising non-rewards activated the frontoinsular cortex bilaterally and deactivated the ventral striatum. In turn, conflict activated a broad network associated with cognitive control and motor functions. Interaction effects showed decreased activity in the thalamus, anterior cingulated gyrus, and middle frontal gyrus bilaterally when difficult conflict trials (e.g., incongruent targets) were preceded by reward cues; in contrast, the ventral striatum and orbitofrontal cortex showed greater activation during congruent targets preceded by reward cues. These results suggest that reward anticipation is associated with lower activation in attentional networks, possibly due to increased processing efficiency, whereas more difficult, conflict trials are associated with lower activity in regions of the reward system, possibly because such trials are experienced as less rewarding.

【 授权许可】

CC BY-NC   
© 2012 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.

Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.