Purchase this article with an account.
Lisa O'Kane, Pascal Mamassian; Temporal dynamics of the motion aftereffect. Journal of Vision 2005;5(8):150. doi: https://doi.org/10.1167/5.8.150.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Staring at a moving display for a few seconds generates a long-lasting aftereffect in the opposite direction. We are interested in the temporal dynamics of motion aftereffects when the test stimulus is presented at various speeds. Due to the end of the aftereffect being a very subjective and delicate event to determine, we provide a new method to estimate the duration of the motion aftereffect. Participants adapted to random dot kinematograms (RDKs) for a period of 5 seconds. To reduce eye movements, two RDKs were placed on either side of the fixation point, moving in opposite directions (e.g. outwards motion). Following a brief interval, the adapting stimuli were replaced by test stimuli whose direction was identical (outwards) but whose speed was a fraction of the adapting speed. If the speed was small, the perceived direction of the test stimulus was initially opposite to its physical direction (inwards) and slowly reverted to the true direction (outwards). We prompted observers to repeatedly judge the perceived direction of the test stimulus in order to estimate the time of reversal. We took this time of reversal as our measure of the duration of the motion aftereffect, and estimated these durations for various test speeds. We found that the duration of the aftereffect depended on the speed of the test surface. Specifically, the slower the speed of the test stimulus, the longer the aftereffect lasted. In summary, we present a new method of investigating the motion aftereffect which offers a robust estimate of the temporal dynamics of the aftereffect.
This PDF is available to Subscribers Only