Article

Neuroimaging studies on attention-deficit/hyperactivity disorder (ADHD) suggest
dysfunctional reward processing, with hypo-responsiveness during reward
anticipation in the reward system including the nucleus accumbens (NAcc). In this study, we investigated the association between ADHD related behaviors and the
reward system using functional magnetic resonance imaging in a non-clinical
sample. Participants were 31 healthy, female undergraduate students with varying
levels of self-reported ADHD related behaviors measured by the adult ADHD
self-report scale. The anticipation of different types of reward was
investigated: monetary reward, punishment avoidance, and verbal feedback. All
three reward anticipation conditions were found to be associated with increased
brain activation in the reward system, with the highest activation in the
monetary reward anticipation condition, followed by the punishment avoidance
anticipation condition, and the lowest activation in the verbal feedback
anticipation condition. Most interestingly, in all three conditions, NAcc
activation was negatively correlated with ADHD related behaviors. In conclusion,
our results from a non-clinical sample are in accordance with reported deficits
in the reward system in ADHD patients: the higher the number and severity of ADHD
related behaviors, the lower the neural responses in the dopaminergic driven
reward anticipation task.
Thus, our data support current aetiological models of
ADHD which assume that deficits in the reward system might be responsible for
many of the ADHD related behaviors.
CI - Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Langue : ANGLAIS