Event-related potentials associated with auditory attention capture in younger and older adults

A deviant-related negativity (DRN), mismatch negativity (MMN), and P3a are electrophysiological measures thought to reflect processes involved in the involuntary switching of attention to a task-irrelevant stimulus. The purpose of this article was to determine whether healthy older adults involuntarily detect unattended auditory stimuli as efficiently as younger adults. To test this, 20 younger adults (aged 18-30 years) and 20 older adults (aged 65+ years) were presented with to-be-ignored auditory sequences consisting of frequently presented 80 dB SPL standards and rarely presented increments (+10 dB) and decrements (-20 dB). The MMN to the decrement did not differ between the 2 groups. On the other hand, the DRN to the increment was significantly reduced in the older adults. Importantly, the P3a was also significantly reduced in the older adults. This reduced P3a may reflect a deficit in the involuntary shift of attention from current cognitive demands to a potentially more critical event.