A neurophysiological evaluation of a cognitive cycle in humans

The present review describes and analyzes several recent papers in which the processes of preparation, evaluation and changing a cue's predictive value on a trial-by-trial basis conform a cycle that permits behavior to be constantly updated. This approach is an extension of Joaquin Fuster's proposal of a "perception-action" cycle in which executive networks are constantly updated as a function of the trials' outcome. The presented results can also be considered in relation to the computational Bayesian brain framework proposed by Friston (2009). The present approach is based on human electrophysiological studies of Posner's central cue paradigm, which provides the possibility to dissociate the following processing steps: (i) preparation for certain stimuli, (ii) evaluation of the validity or invalidity of the preparatory state, and (iii) the feedback cycling of the information extracted from one trial to the next. This trial-by-trial learning would be a potential basis for organism adaptation.