Relationships Between Hearing Status, Cognitive Abilities, and Reliance on Visual and Contextual Cues

Visual and contextual cues facilitate speech recognition in suboptimal listening conditions (e.g., background noise, hearing loss, hearing aid signal processing). Moreover, successful speech recognition in challenging listening conditions is linked to cognitive abilities such as working memory and fluid intelligence. However, it is unclear which cognitive abilities facilitate the use of visual and contextual cues in individuals with normal hearing and hearing aid users. The first aim was to investigate whether individuals with hearing aid users rely on visual and contextual cues to a higher degree than individuals with normal hearing in a speech-in-noise recognition task. The second aim was to investigate whether working memory and fluid intelligence are associated with the use of visual and contextual cues in these groups.

Groups of participants with normal hearing and hearing aid users with bilateral, symmetrical mild to severe sensorineural hearing loss were included (n = 169 per group). The Samuelsson and Rönnberg task was administered to measure speech recognition in speech-shaped noise. The task consists of an equal number of sentences administered in the auditory and audiovisual modalities, as well as without and with contextual cues (visually presented word preceding the sentence, e.g.,: "Restaurant"). The signal to noise ratio was individually set to 1 dB below the level obtained for 50% correct speech recognition in the hearing-in-noise test administered in the auditory modality. The Reading Span test was used to measure working memory capacity and the Raven test was used to measure fluid intelligence. The data were analyzed using linear mixed-effects modeling.

Both groups exhibited significantly higher speech recognition performance when visual and contextual cues were available. Although the hearing aid users performed significantly worse compared to those with normal hearing in the auditory modality, both groups reached similar performance levels in the audiovisual modality. In addition, a significant positive relationship was found between the Raven test score and speech recognition performance only for the hearing aid users in the audiovisual modality. There was no significant relationship between Reading Span test score and performance.

Both participants with normal hearing and hearing aid users benefitted from contextual cues, regardless of cognitive abilities. The hearing aid users relied on visual cues to compensate for the perceptual difficulties, reaching a similar performance level as the participants with normal hearing when visual cues were available, despite worse performance in the auditory modality. It is important to note that the hearing aid users who had higher fluid intelligence were able to capitalize on visual cues more successfully than those with poorer fluid intelligence, resulting in better speech-in-noise recognition performance.