JE Roberts MSc and AJ Wilkins Dphil – University of Essex
Abstract
When driving at night, flickering automobile LED tail lights can appear as multiple
images. The perception of a flickering source of light was therefore studied during rapid
eye movements (saccades) of 20‐40 degrees amplitude in an otherwise dark room
(<1lux). The temporal modulation appeared as a spatial pattern known as a “phantom
array” during the saccade. The appearance of the pattern enabled the discrimination of
flicker from steady light at frequencies that in 11 observers averaged 1.98kHz. At a
frequency of 120Hz the intrasaccadic pattern was perceptible when the contrast of the
flicker exceeded 10%. It is possible that intrasaccadic stimulation interferes with ocular
motor control.