Audiovisual speech perception in Williams syndrome.

Area of Science:

• Neuroscience
• Genetics
• Psychology

Background:

• Williams syndrome (WS) presents a unique cognitive profile with relative strengths in verbal and social communication, contrasted by significant visuo-spatial impairments.
• Face processing, though often considered relatively spared, can exhibit developmental immaturities in WS, prompting further investigation into visual perception.
• Understanding visual and audiovisual speech perception is crucial given the specific cognitive characteristics of WS.

Purpose of the Study:

• To investigate visual and audiovisual speech perception in individuals with Williams syndrome.
• To compare the performance of WS participants with age-matched controls in identifying speech tokens under unimodal and audiovisual conditions.

Main Methods:

• A novel speech perception test was developed using digitally manipulated tokens of English syllables (e.g., /ba:/, /va:/).
• Participants identified speech tokens presented in unimodal (vision or audition alone) and audiovisual conditions.
• Performance was assessed by comparing WS participants to age-matched controls.

Main Results:

• WS participants demonstrated significant impairment in visual speech identification compared to controls.
• Auditory identification of speech tokens was not significantly different between WS participants and controls.
• While audiovisual integration was present in WS, the influence of visual information on auditory perception was reduced.

Conclusions:

• Individuals with Williams syndrome exhibit deficits in visual speech perception, affecting their ability to utilize visual cues during speech processing.
• Despite age-appropriate auditory phonological abilities, speech-reading skills may not reach age-appropriate levels in WS.
• These findings highlight specific challenges in multisensory speech perception within the WS population.