Asymmetry of P3 amplitude during oddball tasks reflects the unnaturalness of visual stimuli.
This study examined the relationship between the 'naturalness' of a visual stimulus and the event-related potentials measured during an oddball task. The study focused on asymmetry of the P3 amplitude during an oddball task or P3 asymmetry. Participants performed two visual oddball tasks using a pair of stimuli (A and B): one in which A was the target stimulus and B was the standard stimulus and vice versa. The stimuli consisted of natural-unnatural pairs of visual stimuli (e.g. upright-inverted faces, possible-impossible human poses). As a result of comparing the amplitudes of the target stimuli, P3 asymmetry was found in natural-unnatural pairs; that is, their naturalness differentiated the target P3 amplitude: larger P3 to the unnatural target than to the natural one. This study showed that P3 asymmetry reflected unnaturalness and unfamiliarity of visual stimuli.
Intelligent Sensing System Research Center, Toyohashi University of Technology, Toyohashi, Aichi, Japan. adrian.williams@brunel.ac.uk
Tetsuto
T
Minami
Kimiko
K
Goto
Michiteru
M
Kitazaki
Shigeki
S
Nakauchi
D000328:Adult; D000704:Analysis of Variance; D004192:Discrimination, Psychological / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D055815:Young Adult