Effects of task complexity on perceptual organization of speech cues by older listeners

Abstract

Older adults with and without clinically significant hearing loss often report difficulty communicating in multitalker environments. Past work in our laboratory has shown that older listeners with hearing loss benefit less from differences in talkers’ vocal characteristics (e.g., fundamental‐frequency differences) relative to younger listeners with comparable hearing losses. The present study examined the extent to which age‐related changes in the perceptual organization of speech cues are due to task demand. Two experiments used the Coordinate Response Measure to examine how the benefit listeners derive from talker characteristics interacts with the complexity of the response task as a function of both age and hearing status. Stimuli were amplified to assure audibility for listeners with hearing loss. Task complexity depended on whether the distracting signal was linguistically meaningful as well as the level of auditory processing required (discrimination versus identification). Older listeners generally benefited more from talker characteristics when task complexity was reduced (e.g., nonmeaningful distracter). The results are interpreted in the context of an information‐processing model in which the increased difficulty of older listeners in multitalker environments is a consequence of reallocating limited resources towards the initial stages of processing at the expense of higher‐level stages. [Work supported by Centers for Disease Control.]