title: Decreased beta-band activity is correlated with disambiguation of hidden figures.
abstract: Insight is commonly described as sudden comprehension, sometimes called an "Aha! moment." In everyday life, we apply the process of insight to problems that are difficult to solve at first glance or that we perceive as ambiguous; however the brain dynamics underlying the disambiguation process remains elusive. Beta-band oscillatory brain activity has been hypothesized to reflect the transition of cognitive states. To elucidate the neural mechanism of insight, we recorded electroencephalograms while subjects were presented with hidden figures followed by unambiguous, gray images. We identified oscillatory activity to detect temporal changes, and compared brain activity that occurred during a perceptual transition with activity that occurred when no perceptual transition occurred. Statistical comparison confirmed stronger beta-power decrease during perceptual transition. Source analysis indicated that the beta-power decrease was around the parietal-posterior regions, mainly in the precuneus. We propose that beta-band desynchronization in the parietal-posterior regions reflects the disambiguation process, and our findings provide additional support for the theory that beta-band activity is related to the transition of cognitive state.
authors.affiliation: Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan. Electronic address: minami@tut.jp.
authors.forename: Tetsuto
authors.initials: T
authors.lastname: Minami
authors.affiliation: Department of Information and Computer Sciences, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Noritake
authors.affiliation: Department of Information and Computer Sciences, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Nakauchi
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001611:Beta Rhythm / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D004192:Discrimination, Psychological / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult
keywords: Beta-band activity; Electroencephalogram; Insight; Object recognition