The role of the Supplementary Motor Area in time processing. The neural bases of timing mechanisms (0.1-100s range) are the subject of much debate. We hypothesise that the Supplementary Motor Area (SMA), a major cortical structure involving important dopaminergic pathways, subtends duration encoding, in the way depicted by the 'accumulator model'. Using transcranial magnetic stimulation (TMS) over the SMA, we will test healthy subjects in motor and perceptual timing tasks, compared to Parkinson' ....The role of the Supplementary Motor Area in time processing. The neural bases of timing mechanisms (0.1-100s range) are the subject of much debate. We hypothesise that the Supplementary Motor Area (SMA), a major cortical structure involving important dopaminergic pathways, subtends duration encoding, in the way depicted by the 'accumulator model'. Using transcranial magnetic stimulation (TMS) over the SMA, we will test healthy subjects in motor and perceptual timing tasks, compared to Parkinson's disease patients whose timing performance is impaired due to dopaminergic dysfunction. We expect TMS inhibitory effects to induce predictable performance trends, providing support for the accumulator model and the key role of the SMA in timing.Read moreRead less