This doctoral thesis aims at understanding the neuropathophysiologic correlates in mood disorders. Several studies working on these pathologies face the lack of objective tools in disease classification and therefore difficulties in differential diagnosis. Neurofonctional changes are mainly based on two models: the frontal hypometabolism, explaining depressive state by a decrease activity in frontal cortical areas and an enhancement in subcortical areas; and an interhemispheric asymmetry model dependent on lateralized emotion theories where interhemispheric imbalance (right hemisphere more active than left) should be the mood disorder correlate. Despite all attempts to eliminate methodological bias, researchers did not find consensus. The aim of this research is to find objective tools about mood disorder with psychophysical (oculometry) and neurophysiological (cortical excitability) techniques. Therefore, we followed patients who received pharmacological medication or transcranial magnetic stimulation (TMS) therapies to observe the effects and to see if intra- or inter-hemispheric unbalances could be demonstrated and then to guide in therapeutic choice. Our results showed the interindividual variability and supposed that each patient could present a specific pathophysiology. In addition, the follow-up for bipolar patients in the different mood states suggests an impairment inversion between maniac and depressive phases. Several deficiencies could engender depressive mood and the choice of target in rTMS therapy could be guided by an objective observation of these deficits.
