Stress modulation of visuomotor binding

The primate cortex represents perceived and produced events in a distributed way, which calls for a mechanism that integrates their features into coherent structures. Animal, drug, and patient studies suggest that the local binding of visual features is under muscarinic-cholinergic control, whereas visuomotor binding seems to be driven by dopaminergic pathways. Consistent with this picture, we present evidence that the binding of visual features and actions is modulated by stress, induced by the cold pressure test (CPT), which causes an excessive dopamine turnover in prefrontal cortex. The impact of stress was restricted to the task-relevant visuomotor binding, supporting claims that dopamine affects the maintenance of task-relevant information in working memory. The outcome pattern, including the impact of the personality trait extraversion, suggests that the relation between dopamine level and visuomotor performance follows an inverted U-shaped function, with strongest binding being associated with average dopamine levels. (C) 2008 Elsevier Ltd. All rights reserved.