Symmetric patterns with different luminance polarity (anti-symmetry) generate an automatic response in extrastriate cortex

Makin, ADJ ORCID: 0000-0002-4490-7400 (2020) Symmetric patterns with different luminance polarity (anti-symmetry) generate an automatic response in extrastriate cortex European Journal of Neuroscience, 51 (3). pp. 922-936. ISSN 0953-816X, 1460-9568

Access the full-text of this item by clicking on the Open Access link.

Text Makin_et_al-2019-European_Journal_of_Neuroscience.pdf - Published version Download (2MB) | Preview

Abstract

People can quickly detect bilateral reflection in an image. This is true when elements of the same luminance are matched on either side of the axis (symmetry) and when they have opposite luminance polarity (anti-symmetry). Using electroencephalography, we measured the well-established sustained posterior negativity (SPN) response to symmetry and anti-symmetry. In one task, participants judged the presence or absence of regularity (Regularity Discrimination Task). In another, they judged the presence or absence of rare colored oddball trials (Colored Oddball Task). Previous work has concluded that anti-symmetry is only detected indirectly, through serial visual search of element locations. This selective attention account predicts that the anti-symmetry SPN should be abolished in the Colored Oddball Task because there is no need to search for anti-symmetry. However, this prediction was not confirmed: The symmetry and anti-symmetry SPN waves were not modulated by task. We conclude that at least some forms of anti-symmetry can be extracted from the image automatically, in much the same way as symmetry. This is an important consideration for models of symmetry perception, which must be flexible enough to accommodate opposite luminance polarity, while also accounting for the fact anti-symmetry is often perceptually weaker than symmetry.

Item Type:	Article
Uncontrolled Keywords:	electroencephalography, event-related potentials, lateral occipital complex, sustained posterior negativity, symmetry
Depositing User:	Symplectic Admin
Date Deposited:	10 Oct 2019 09:00
Last Modified:	16 Jun 2026 07:08
DOI:	10.1111/ejn.14579
Open Access URL:	https://doi.org/10.1111/ejn.14579
Related Websites:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3057681
Disclaimer:	The University of Liverpool is not responsible for content contained on other websites from links within repository metadata. Please contact us if you notice anything that appears incorrect or inappropriate.