Involvement of V5/MT+ in object substitution masking: evidence from repetitive transcranial magnetic stimulation.
The visibility of a briefly presented target can be reduced by a subsequent weak mask that does not touch it, when the target is encoded in low spatiotemporal resolution. This phenomenon, called object substitution masking, has recently been proposed to reflect information updating in object-level representation, with perception of the target and the mask belonging to a single object through apparent motion. We investigated this issue by applying repetitive transcranial magnetic stimulation over V5/MT+, specialized in visual motion processing. The transient functional disruption of V5/MT+ produced by repetitive transcranial magnetic stimulation attenuated object substitution masking, while sham stimulation did not. Our results suggest that object substitution masking is mediated by normal functioning of V5/MT+. We conclude that repetitive transcranial magnetic stimulation of V5/MT+ impaired perceived object continuity and reduced object substitution masking accordingly.
Hirose
Nobuyuki
N
Department of Psychology, Kyoto University, Sakyo, Kyoto 606-8501, Japan. nhirose@bun.kyoto-u.ac.jp
Kihara
Ken
K
Tsubomi
Hiroyuki
H
Mima
Tatsuya
T
Ueki
Yoshino
Y
Fukuyama
Hidenao
H
Osaka
Naoyuki
N
D000328:Adult; D004558:Electric Stimulation / Q000379:methods; D007839:Functional Laterality / Q000502:physiology / Q000528:radiation effects; D006801:Humans; D009039:Motion Perception / Q000502:physiology* / Q000528:radiation effects; D010470:Perceptual Masking / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D050781:Transcranial Magnetic Stimulation / Q000009:adverse effects; D014793:Visual Cortex / Q000502:physiology* / Q000528:radiation effects; D014796:Visual Perception / Q000502:physiology* / Q000528:radiation effects