Right lateralized alpha desynchronization increases with the proportion of symmetry in the stimulus.

Makin, Alexis DJ ORCID: 0000-0002-4490-7400, Tyson-Carr, John ORCID: 0000-0003-3364-2184, Rampone, Giulia ORCID: 0000-0002-2710-688X, Morris, Amie and Bertamini, Marco ORCID: 0000-0001-8617-6864
(2021) Right lateralized alpha desynchronization increases with the proportion of symmetry in the stimulus. The European journal of neuroscience, 53 (9). pp. 3175-3184.

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Research into the neural basis of symmetry perception has intensified in the last two decades, however the functional role of neural oscillations remains unclear. In previous work (Makin et al., 2014, Wright et al., 2015) examined occipital alpha Event-Related Desynchronization (alpha ERD). It was concluded that alpha ERD is right lateralized during active regularity discrimination, but not during a secondary task. Furthermore, alpha ERD was unaffected by stimulus properties, such as the type of regularity. These conclusions are refuted by new time-frequency analysis on an EEG data set first introduced by Makin et al. (2020). We compared alpha ERD across five tasks. First, we found that right lateralization of alpha ERD was evident in all tasks, not just active regularity discrimination. This was caused by hemispheric differences in alpha power during pre-stimulus baseline (left < right), which equalized after stimulus onset (left = right). Second, we found that Alpha ERD increased with the proportion of symmetric elements in the image (PSYMM). Sensitivity to PSYMM was stronger on the right. These findings suggest known extrastriate symmetry activations are accompanied by reduced alpha power.

Item Type: Article
Uncontrolled Keywords: EEG, LOC, neural oscillations, regularity, time&#8208, frequency analysis
Divisions: Faculty of Health and Life Sciences
Faculty of Health and Life Sciences > Institute of Population Health
Depositing User: Symplectic Admin
Date Deposited: 17 Mar 2021 12:18
Last Modified: 18 Jan 2023 22:56
DOI: 10.1111/ejn.15176
Open Access URL: http://doi.org/10.1111/ejn.15176
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3117547