Electrophysiological priming effects confirm that the extrastriate symmetry network is not gated by luminance polarity.
Eur J Neurosci
; 53(4): 964-973, 2021 02.
Article
en En
| MEDLINE
| ID: mdl-32897595
ABSTRACT
It is known that the extrastriate cortex is activated by visual symmetry. This activation generates an ERP component called the Sustained Posterior Negativity (SPN). SPN amplitude increases (i.e., becomes more negative) with repeated presentations. We exploited this SPN priming effect to test whether the extrastriate symmetry response is gated by element luminance polarity. On each trial, participants observed three stimuli (patterns of dots) in rapid succession (500 ms. with 200 ms. gaps). The patterns were either symmetrical or random. The dot elements were either black or white on a grey background. The triplet sequences either showed repeated luminance (black > black > black, or white > white > white) or changing luminance (black > white > black, or white > black > white). As predicted, SPN priming was comparable in repeated and changing luminance conditions. Therefore, symmetry with black elements is not processed independently from symmetry with white elements. Source waveform analysis confirmed that this priming happened within the extrastriate symmetry network. We conclude that the network pools information across luminance polarity channels.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Corteza Visual
/
Electroencefalografía
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Eur J Neurosci
Asunto de la revista:
NEUROLOGIA
Año:
2021
Tipo del documento:
Article
País de afiliación:
Reino Unido