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The study examined the partner-directed gaze patterns of old and young talkers in a task (DiapixUK) that involved two people (a lead talker and a follower) engaging in a spontaneous dialogue. The aim was (1) to determine whether older adults engage less in partner-directed gaze than younger adults by measuring mean gaze frequency and mean total gaze duration; and (2) examine the effect that mild hearing loss may have on older adult’s partner-directed gaze. These were tested in various communication conditions: a no barrier condition; BAB2 condition in which the lead talker and the follower spoke and heard each other in multitalker babble noise; and two barrier conditions in which the lead talker could hear clearly their follower but the follower could not hear the lead talker very clearly (i.e., the lead talker’s voice was degraded by babble (BAB1) or by a Hearing Loss simulation (HLS). 57 single-sex pairs (19 older adults with mild Hearing Loss, 17 older adults with Normal Hearing and 21 younger adults) participated in the study. We found that older adults with normal hearing produced fewer partner-directed gazes (and gazed less overall) than either the older adults with hearing loss or younger adults for the BAB1 and HLS conditions. We propose that this may be due to a decline in older adult’s attention to cues signaling how well a conversation is progressing. Older adults with hearing loss, however, may attend more to visual cues because they give greater weighting to these for understanding speech.

When someone speaks, linguistically relevant movements are produced. Most of the previous work that has examined the visual manifestation of speech has investigated regions around the oral aperture and sometimes the jaw. In the current work we examined whether people could use visual information from the top part of the talker’s face to determine which of two sentences had been uttered. In the first experiment observers saw two pairs of short video clips that showed the top part of a talker’s head as the person uttered a sentence. The audio component of the video was not played. The task was to judge the pair of videos in which the talker said the same sentence (different tokens were used). Observers were able to make this judgment at better than chance levels (on average 71% correct). In the second experiment, the same participants were presented with auditory-visual pairs and had to select in which pair the talker said the same sentence. Once again matching performance was above chance (69% correct). Taken together, the results indicate that participants are sensitive to the speech relatedness of movements from the upper part of the head and face. Implications for audio-visual speech processing as well as for the development of virtual characters are considered.