Visual word recognition in two facial motion conditions: full-face versus lips-plus-mandible

Area of Science:

• Audiology
• Speech Science
• Visual Perception

Background:

• Visual speech information, or lipreading, aids auditory speech perception, especially for individuals with hearing loss.
• The extent of facial visual cues necessary for effective speechreading remains an area of investigation.

Purpose of the Study:

• To investigate the impact of reduced facial visual information on speechreading monosyllabic words.
• To compare speechreading performance between full-face and part-face (lips-plus-mandible) conditions.
• To examine the effect of repeated exposure on speechreading accuracy.

Main Methods:

• A new method developed video sequences with limited facial movement exposure.
• A repeated-measures design assessed visual recognition of 60 monosyllabic words in an open set.
• Normal-hearing students and adults with sensorineural hearing loss speechread video presentations under full-face and part-face conditions.

Main Results:

• Phoneme recognition scores were comparable between the full-face and part-face conditions.
• Speechreading scores significantly improved with repeated measures, irrespective of the facial exposure condition.
• Both normal-hearing and hearing-impaired participants demonstrated effective speechreading with limited facial cues.

Conclusions:

• Speechreaders can effectively recognize spoken words using only the lips-plus-mandible visual information.
• Practice effects significantly enhance speechreading performance, highlighting the role of familiarity and adaptation.
• These findings have implications for understanding visual speech perception and developing assistive listening technologies.