Study of Bipolar Disorders and Retinal Electrophysiological Markers

The BIMAR study aims to compare electrophysiological data measured with electroretinogram (ERG) and electroencephalogram (EEG) between a group of euthymic patients with bipolar disorder (BD) and a group of healthy controls subjects. Secondarily, the investigators also want to: * Compare combined electrophysiological measurements with ERG and EEG between the two groups. * Identify relations between clinical, neuropsychological and circadian phenotypes in patients with BD and electrophysiological measurements measured with ERG and EEG. The main hypothesis of the investigators is that differences exist in the ERG and EEG measurements between subjects with BD and healthy subjects. Those differences could be identified as candidate markers for BD which, if confirmed in later studies, could be used in current practice to guide the management of patients with BD.