Effective exploration of the environment, check for information to improve one's own performance, are fundamental abilities of human cognition. These abilities are dependent on the process of cognitive control.

However, they are clearly impaired and uncontrollable in certain behavioral disorders such as obsessive-compulsive disorder (OCD). Compulsive checks of these patients, spontaneously associated with a feeling of intense uncertainty, suggest disturbances of evaluative and metacognitive functions. However, no biological observations have yet been able to feed these hypotheses.

The evaluation of decisions and actions involves the middle cingulate cortex (MCC) (which belongs to a cortico-subcortical network structurally and functionally altered in OCD patients). Cingulotomy has long been used as a therapy in severe OCD, with However, the precise part of the cingulate cortex that contributes to check (and its pathological forms) remains to be discovered.

The purpose of this research campaign is to determine, through functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) in healthy human subjects:

1. the location and role of the MCC region involved in normal check decision processes,
2. determine the identity of the entire network involved

Inclusion Criteria:

• adults age range 20-45 years
• being able to provide a written consent form
• having a social insurance
• have a normal vision (with or without corrections)
• Right-handed

Exclusion Criteria:

• Subjects with MRI contraindications (e.g. pacemaker, claustrophobia, metal in the body, etc…).
• Pregnant subjects
• Subjects with neurological history
• Subjects must be willing to be advise in case of discovery of brain abnormality.