TMS in bipolar disorder

This article reviews the existing animal and human literature on the clinical potential of transcranial magnetic stimulation (TMS) in mania and bipolar depression, and discusses potential future directions for this work. Studies of TMS in depression and normal volunteers suggested lateral specificity of TMS-induced mood effects. Clinical trials to compare left versus right prefrontal TMS in mania have been developed. Studies to understand the effect of TMS in bipolar depression have been undertaken. The results show efficacy similar to that for unipolar depression. But this does not provide support for the concept of TMS as an anti-bipolar, or mood-stabilizing, treatment. The utility of TMS as prophylaxis for subsequent manic or depressive episodes has not been reported in bipolar disorder. More work is needed to clarify the risk of mood switch, and the potential of TMS as prophylaxis against future manic or depressive episodes.

Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purposes. After a single session of exposing simple manual pointing to left-deviating prisms, contrary to healthy controls, none of the patients showed a reliable change of the straight-ahead pointing movement in the dark. No significant modification of attentional paper-and-pencil tasks was either observed immediately or 2 hours after prism adaptation. These results suggest that the therapeutic effect of prism adaptation on left spatial neglect relies on a specific lateralized mechanism. Evidence for a directional effect for prism adaptation both in terms of the side of the visuomanual adaptation and therefore possibly in terms of the side of brain affected by the stimulation is discussed.