Listening in noise: what can ability to memorise tones tell us about hearing impaired listeners?
Currently, hearing aids are adjusted on the basis of pure tone audiometry. In other words, we are trying to infer an individual’s communication difficulties in every day situations, based on their ability to hear a few barely audible static pure tones. In reality, the nature of living organisms is such that reactions to dynamic changes in sensory inputs are often more important than reactions to static inputs. We are living, breathing change detectors. Tracking changes in the environment requires attention and memory, both of which enable the comparison of past and present events. This is particularly true in noisy environments.
We have been investigating the relationship between auditory attention, memory and every day listening skills in normal hearing (n = 139, mean age = 64.0 years) and hearing impaired (n = 199, mean age = 66.6 years) listeners. In developing a task that relates attention and short term memory, we combined a recognition memory for pitch task (Deutsch, 1972) and a dynamic attending task (Jones et al., 2002). The resulting memory for tones task consists of auditory rhythmic sequences of low frequency tones (a same–different judgment of a standard and a target tone, separated by a series of six intervening distracting tones). Subjective listening skills were assessed using the short form of Speech, Spatial and Qualities of Hearing Scale (Gatehouse and Noble, 2004; Noble et al. 2013), and questions assessing an individual’s distractibility in noisy environments.
We have found significant correlations between the outcomes of the tone-memorisation task and self-assessed communication difficulties in noise, as well as auditory distractibility, in both normal hearing and hearing impaired listeners. Future research will further assess the ability of this task to provide a link between listening skills, individual performance and preference for different hearing aid settings.