Theta synchronization over occipito‐temporal cortices during visual perception of body parts. (15th December 2017)

• Record Type: Journal Article
• Authors: Moreau, Quentin; Pavone, Enea F.; Aglioti, Salvatore M.; Candidi, Matteo
• Other Names: Mazaheri Ali guestEditor.; Slagter Heleen guestEditor.; Thut Gregor guestEditor.; Foxe John J. guestEditor.
• Is Part Of: European journal of neuroscience. Volume 48:Number 8(2018)
• Page Start: 2826
• Page End: 2835
• Publication Date: 2017-12-15
• Subjects: body parts visual perception -- EEG -- theta band -- time–frequency; Nervous system -- Periodicals; 612.8
• DOI: 10.1111/ejn.13782
• Languages: English
• ISSNs: 0953-816X

Abstract

Abstract: Categorical clustering in the visual system is thought to have evolved as a function of intrinsic (intra‐areal) and extrinsic (interareal) connectivity and experience. In the visual system, the extrastriate body area (EBA), an occipito‐temporal region, responds to full body and body part images under the organizational principle of their functional/semantic meaning. Although frequency‐specific modulations of neural activity associated with perceptive and cognitive functions are increasingly attracting the interest of neurophysiologists and cognitive neuroscientists, perceiving single body parts with different functional meaning and full body images induces time–frequency modulations over occipito‐temporal electrodes are yet to be described. Here, we studied this issue by measuring EEG in participants who passively observed fingers, hands, arms and faceless full body images with four control plant stimuli, each bearing hierarchical analogy with the body stimuli. We confirmed that occipito‐temporal electrodes (compatible with the location of EBA) show a larger event‐related potential (ERP, N190) for body‐related images. Furthermore, we identified a body part‐specific (i.e. selective for hands and arms) theta event‐related synchronization increase under the same electrodes. This frequency modulation associated with the perception of body effectors over occipito‐temporal cortices is in line with recent findings of categorical organization of neural responses to human effectors in the visual system. Abstract : By analyzing time–frequency EEG responses to visual perception of body and body‐part stimuli, we described specific occipito‐temporal theta synchronization during perception of hand and arm images compared to other body‐part (finger) and full body images as well as control images. This finding represents a frequency‐specific marker indicating that neural oscillations in the visual system may highlight body‐part subcategory dissociation.