Auditory areas are recruited for naturalistic visual meaning in early deaf people

• Published in: Nature communications 2024-09, Vol.15 (1), p.8035-13, Article 8035
• Main Authors: Zimmermann, Maria, Cusack, Rhodri, Bedny, Marina, Szwed, Marcin
• Format: Article
• Language: English
• Subjects: 631/378/2649/1310; 631/378/2649/1723; Adult; Auditory Cortex - physiology; Auditory Cortex - physiopathology; Auditory Perception - physiology; Auditory system; Auditory tasks; Brain Mapping; Cortex (auditory); Deafness; Deafness - congenital; Deafness - physiopathology; Female; Hearing loss; Hemispheres; Hemispheric laterality; Heterogeneity; Humanities and Social Sciences; Humans; Information processing; Magnetic Resonance Imaging; Male; multidisciplinary; Photic Stimulation; Science; Science (multidisciplinary); Sensory integration; Statistical analysis; Visual observation; Visual Perception - physiology; Visual stimuli; Visual tasks; Young Adult
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-52383-6

Congenital deafness enhances responses of auditory cortices to non-auditory tasks, yet the nature of the reorganization is not well understood. Here, naturalistic stimuli are used to induce neural synchrony across early deaf and hearing individuals. Participants watch a silent animated film in an intact version and three versions with gradually distorted meaning. Differences between groups are observed in higher-order auditory cortices in all stimuli, with no statistically significant effects in the primary auditory cortex. Comparison between levels of scrambling revealed a heterogeneity of function in secondary auditory areas. Both hemispheres show greater synchrony in the deaf than in the hearing participants for the intact movie and high-level variants. However, only the right hemisphere shows an increased inter-subject synchrony in the deaf people for the low-level movie variants. An event segmentation validates these results: the dynamics of the right secondary auditory cortex in the deaf people consist of shorter-length events with more transitions than the left. Our results reveal how deaf individuals use their auditory cortex to process visual meaning. In people who are deaf, the parts of the brain usually responsible for processing audition can take over visual tasks. Here, the authors show that the auditory cortex in early deaf individuals processes visual meaning conveyed in naturalistic stimuli.