Peripheral Visual Reaction Time Is Faster in Deaf Adults and British Sign Language Interpreters than in Hearing...

Area of Science:

• Neuroscience
• Visual Cognition
• Sensory Compensation

Background:

• Auditory deprivation can lead to enhanced visual cognition, particularly in near peripheral vision.
• Far peripheral vision, where acuity is poor, may benefit most from auditory input in hearing individuals.
• Visuospatial languages like British Sign Language (BSL) impose additional demands on the visual system.

Purpose of the Study:

• To investigate the distinct effects of deafness and visuospatial language use on far peripheral visual processing.
• To compare visual reaction times (RTs) and accuracy across different groups in response to peripheral stimuli.

Main Methods:

• Tested visually normal adults: profoundly congenitally deaf (N=17), hearing fluent BSL users (N=8), and hearing non-signers (N=18).
• Utilized a peripheral forced choice paradigm with static, briefly illuminated stimuli at varying luminances (30°-85° meridians).

Main Results:

• Deaf adults exhibited significantly faster RTs to all far peripheral stimuli compared to both hearing groups.
• RT differences were consistent across visual field meridians and not localized to specific regions.
• No significant differences in stimulus detection accuracy were observed between any groups.

Conclusions:

• Early-onset profound auditory deprivation confers a visual response time advantage in the far periphery.
• BSL fluency enhances peripheral visuo-motor responses, though to a lesser degree than congenital deafness.