Visual perceptual echo reflects learning of regularities in rapid luminance sequences

Chang, Acer Y-C, Schwartzman, David, VanRullen, Rufin, Kanai, Ryota and Seth, Anil K (2017) Visual perceptual echo reflects learning of regularities in rapid luminance sequences. Journal of Neuroscience, 37 (35). pp. 8486-8497. ISSN 0270-6474

[img] PDF - Accepted Version
Restricted to SRO admin only until 30 February 2018.

Download (987kB)

Abstract

A novel neural signature of active visual processing has recently been described in the form of the ‘perceptual echo’, in which the cross-correlation between a sequence of randomly fluctuating luminance values and occipital electrophysiological (EEG) signals exhibits a long-lasting periodic (~100ms cycle) reverberation of the input stimulus (VanRullen & Macdonald, 2012). As yet, however, the mechanisms underlying the perceptual echo and its function remain unknown. Reasoning that natural visual signals often contain temporally predictable, though non-periodic features, we hypothesized that the perceptual echo may reflect a periodic process associated with regularity learning. To test this hypothesis, we presented subjects with successive repetitions of a rapid non-periodic luminance sequence, and examined the effects on the perceptual echo, finding that echo amplitude linearly increased with the number of presentations of a given luminance sequence. These data suggest that the perceptual echo reflects a neural signature of regularity learning.

Furthermore, when a set of repeated sequences was followed by a sequence with inverted luminance polarities, the echo amplitude decreased to the same level evoked by a novel stimulus sequence. Crucially, when the original stimulus sequence was re-presented, the echo amplitude returned to a level consistent with the number of presentations of this sequence, indicating that the visual system retained sequence specific information, for many seconds, even in the presence of intervening visual input.

Altogether, our results reveal a previously undiscovered regularity learning mechanism within the human visual system, reflected by the perceptual echo.

Item Type: Article
Schools and Departments: School of Engineering and Informatics > Informatics
Research Centres and Groups: Sackler Centre for Consciousness Science
Subjects: R Medicine > RC Internal medicine > RC0321 Neurosciences. Biological psychiatry. Neuropsychiatry
Depositing User: Marianne Cole
Date Deposited: 05 Jul 2017 11:24
Last Modified: 18 Oct 2017 15:31
URI: http://sro.sussex.ac.uk/id/eprint/69057

View download statistics for this item

📧 Request an update