label: Fixation-off epileptiform discharges
label_lc: fixation-off epileptiform discharges
description: "Fixation off sensitivity (FOS) is characterized by posterior or generalized epileptiform discharges that consistently occur with conditions that eliminate central vision, such as closed eyes, complete darkness, modified Ganzfeld stimulation (using a large white surface without visual cues), and Frenzel lenses. The FOS electroencephalogram (EEG) pattern usually consists of spikes/polyspikes and waves localized in occipital regions (bilateral or unilateral) or generalized discharges. It is usually inhibited by fixation of gaze, observing patterns, or intermittent photic stimulation (e.g., flashing light or patterns used as stimuli during the recording of the EEG)."