Visual mismatch negativity elicited by magnocellular system activation

The processing of visual motion was tested by means of event related potentials recording (ERP) using a paradigm designed to produce a visual mismatch negativity effect. The stimuli were unattended and presented in the peripheral visual field (outside the central 15°). The standard stimulus consisted of an up/down motion sequence, whilst the deviant stimulus of a down/up motion sequence. Significant ERP differences between the standard and deviant conditions were found in 8 out of 10 adult subjects already in 80 ms and prevailingly in interval 145–260 ms from the initial stimulus presentation. The results demonstrate that the magnocellular information undergoes processing capable of detecting differences in the sequence of unattended peripheral motion stimuli.