[Electrophysiology of executive functions].

INTRODUCTION

In neuropsychology, executive functions have been defined as those that coordinate the flow of information processing in the brain. In the last decade its study has undergone an important development, partly due to the use of functional neuroimaging.

DEVELOPMENT

Electrophysiological techniques have also provided a link between two specific components of the event related brain potential (ERP) and certain control and monitoring processes, as those described in theoretical frameworks of executive functioning (i.e., Norman & Shallice). On the one hand, attentional set shifting paradigms allow us to relate the anteriorly (P3a; latency 300-350 ms) and posteriorly (P3b; latency 450-600 ms) distributed components of the so called 'novelty P3', with a more general mechanism of attentional set shifting that could account for both stimulus and task novelty. On the other hand, 'error related negativity' (ERN or En) has shown its sensitivity to action monitoring (i.e., error detection and error correction processes), during the execution of response selection RT tasks.

CONCLUSIONS

The comprehension of these two executive processes represents critical aspects in our understanding of brain function, and has direct applications to the design of both theoretical models and assessment and rehabilitation programs for patients with dysexecutive disorders.