Older adults show impaired modulation of attentional alpha oscillations: Evidence from the cocktail party

Auditory attention is critical for selective listening to speech from a single talker in a multi-talker environment (e.g., the cocktail party problem, Cherry, 1953). This type of listening is notoriously more difficult and more poorly encoded to longterm memory in older adults than in young adults (Tun, O’Kane, & Wingfield, 2002). Recent work by Payne et al. (2016) in young adults demonstrated a neural correlate of auditory attention in the directed dichotic listening task (DDLT), where listeners are required to attend to one ear while ignoring the other. Measured using electroencephalography (EEG), differences in alpha band power (8-13 Hz) between left and right hemisphere parietal regions mark the direction to which auditory attention is focused. Little prior research has been conducted on alpha power modulations in older adults, particularly with regard to auditory attention directed toward speech stimuli. In the current study, a sample of 19 older adults were run through the DDLT and delayed recognition procedure used by Payne et al. (2016). Compared to the young adults, older adults showed reduced selective attention in the DDLT, evidenced by a higher rate of intrusions from the unattended channel. Moreover, older adults did not exhibit the attentionrelated alpha modulation evidenced by young adults, nor did their ERPs to recognition probes differentiate between attended or unattended probes. Lastly, older adults did not show any behavioral differentiation between attended and unattended probes during a delayed recognition test, which Payne et al. (2016) reported finding a carryover suppression effect for unattended words by the young adults. We interpret these results as evidence for an age-related decline in selective auditory attention, potentially mediated by an age-related decline in the ability to modulate alpha oscillations.
 Under review, Psychophysiology