Developmental experiences alter the temporal processing characteristics of the visual cortex: Evidence from deaf and hearing native signers

Abstract

To date, the extent to which early experience shapes the functional characteristics of neural circuits is still a matter of debate. In the present study, we tested whether congenital deafness and/or the acquisition of a sign language alter the temporal processing characteristics of the visual system. Moreover, we investigated whether, assuming cross‐modal plasticity in deaf individuals, the temporal processing characteristics of possibly reorganised auditory areas resemble those of the visual cortex. Steady‐state visual evoked potentials (SSVEPs) were recorded in congenitally deaf native signers, hearing native signers, and hearing nonsigners. The luminance of the visual stimuli was periodically modulated at 12, 21, and 40 Hz. For hearing nonsigners, the optimal driving rate was 12 Hz. By contrast, for the group of hearing signers, the optimal driving rate was 12 and 21 Hz, whereas for the group of deaf signers, the optimal driving rate was 21 Hz. We did not observe evidence for cross‐modal recruitment of auditory cortex in the group of deaf signers. These results suggest a higher preferred neural processing rate as a consequence of the acquisition of a sign language.

Stronger neural response to canonical finger‐number configurations in deaf compared to hearing adults revealed by FPVS‐EEG

“…This method provides an objective marker of category discrimination and has already been successfully applied to the discrimination of visual quantities (Guillaume et al, 2018 ; Marlair et al, 2021 ), digits grouped on the basis of parity (odd/even) or magnitude (small/big) (Guillaume et al, 2020 ; Marinova et al, 2021 ), or digits among letters (Lochy & Schiltz, 2019 ). It has also been successfully used to investigate visual processing and brain reorganisation in deaf individuals (Benetti et al, 2017 ; Bottari et al, 2020 ; Gwinn & Jiang, 2020 ; Retter et al, 2019 ; Stroh et al, 2022 ) and is therefore particularly adapted to unravel changes associated with number categorizations in deaf signers.…”