A motion aftereffect seen more strongly by the non-adapted eye: evidence of multistage adaptation in visual motion processing.
We found that the motion aftereffect measured using a directionally ambiguous counterphase grating (flicker MAE) can be stronger when it is measured for the non-adapted eye than when measured for the adapted eye. The monocularly viewed adaptation stimulus was the movement of a missing-fundamental grating (2f+3f motion), for which the movement of the higher-order spatial structure was dominantly perceived, while the first-order structure was physically moving in the opposite direction. For observers who perceived the MAE consistently in the direction opposite to the movement of the higher-order structures, the MAE was larger for the non-adapted eye than for the adapted eye. This finding of 'over-100% transfer' invalidates the standard view that the IOT is a direct measure of the binocularity of the adapted neurones. In addition, the finding provides convincing support for the hypothesis that the flicker MAE reflects adaptation at multiple processing stages
Nishida
S
S
Human and Information Science Laboratory, NTT Communication Science Laboratories, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan. nishida@apollo3.brl.ntt.co.jp
Ashida
H
H
D000222:Adaptation, Physiological / Q000502:physiology*; D005366:Figural Aftereffect / Q000502:physiology*; D006801:Humans; D009039:Motion Perception / Q000502:physiology*; D011601:Psychophysics; D015348:Vision, Binocular / Q000502:physiology; D015349:Vision, Monocular / Q000502:physiology; D014795:Visual Pathways / Q000502:physiology