Role of human frontal and supplementary eye fields in double step saccades.

Transcranial magnetic stimulation (TMS) was applied over the frontal eye field (FEF) and the supplementary eye field (SEF) regions before execution of the first saccade in a double step task. When applied over the FEF, stimulation increased the percentage error in amplitude of the contralateral second saccade as compared to no stimulation. This was due to an interference with retinotopic but not craniotopic gain calculation. Stimulation of the SEF region interfered with saccade ordering. Thus, FEF might participate in target memorization whereas SEF is confirmed to code order information for sequential saccades even in this paradigm of only two consecutive movements.