Audiovisual incongruent word recognition in children with developmental language disorder: Evidence from eye tracking

Children with developmental language disorder (DLD) have difficulties during audiovisual (AV) speech integration, which can impact their ability to understand and produce speech. We examined whether children with DLD differed in relying on auditory or visual cues compared to typically developing (TD) children during the recognition of words presented with incongruent sound and articulation. The selective attention to the eyes and mouth of a speaker was also tested. We hypothesised that the DLD group would be less aware of visual and auditory speech cues and would tend to look less at the mouth and eyes of the talker's face compared to their TD peers. We recorded children's eye movements with an eye tracker as they looked into the face of a speaking interlocutor. During the task, the speaker's face was articulating a word matched simultaneously with a different word heard. Afterwards, children were asked to choose the word perceived among four drawings. The DLD group showed less accuracy and was more affected by the competitor's words in comparison to the TD group. Moreover, their selective attention was allocated significantly less to the mouth and partially to the eyes of the talker's face in comparison to the control group. AV speech cues are important in speech perception and children with DLD face challenges in processing speech and phonological representations. Interventions that focus on enhancing AV integration through visually salient cues and perceptual learning strategies may be beneficial for improving speech perception outcomes in children with DLD.