Neural processes in pseudo perceptual rivalry: an ERP and time-frequency approach.
Necker cube is one of the ambiguous figures that is physically a static image but can be alternately perceived in two different perspectives. A great deal of debate exists regarding ambiguous figures that induce spontaneous switching between rival percepts. To investigate the time course of neural processes underlying such perceptual rivalry, we recorded electroencephalograms associated with participants' perceptions of a Necker cube under ambiguous and unambiguous conditions, using a modified discontinuous-presentation method. Each condition consisted of two stimuli presented consecutively, starting with an unambiguous stimulus in both conditions. The second stimulus was either ambiguous (ambiguous condition) or unambiguous (control condition). We compared endogenous reversal activity of ambiguous stimuli with exogenous reversals. As a result, we found that the right-occipital beta-band activity (16-26 Hz) increased 100-150 ms and 350-450 ms after the onset of the ambiguous stimulus only when the perception of the ambiguous stimulus differed from that of the first stimulus. These results indicate that activity in the right-occipital total beta band reflects endogenous switching between rivaling percepts.
Center for Information and Neural Networks(CiNet), National Institute of Information and Communications Technology, and Osaka University, 588-2 Iwaoka, Nishi-ku, Kobe, Hyogo 651-2429, Japan.
Y
Y
Yokota
Electronics-Inspired Interdisciplinary Research Institute, Toyohashi University of Technology, 1-1 Hibarigaoka Tempaku, Toyohashi, Aichi 441-8580, Japan. Electronic address: minami@tut.jp.
T
T
Minami
Center for Information and Neural Networks(CiNet), National Institute of Information and Communications Technology, and Osaka University, 588-2 Iwaoka, Nishi-ku, Kobe, Hyogo 651-2429, Japan.
Y
Y
Naruse
Department of Electronic and Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka Tempaku, Toyohashi, Aichi 441-8580, Japan.
S
S
Nakauchi
D000328:Adult; D001611:Beta Rhythm; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D008297:Male; D009903:Optical Illusions / Q000502:physiology*; D010775:Photic Stimulation; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
EEG; Necker cube; beta-band activity; perceptual rivalry