Distraction and re-orientation of attention in elderly people

Berti, S.
Psychological Institute, Johannes Gutenberg-University Mainz, Germany
E-mail: berti@uni-mainz.de

An important pre-requisite of adaptive behaviour is a balance of involuntary and voluntary attention in order to be able to react on unexpected changes in the environment even when focusing on task demands. The coordination of distractibility and focusing is essential during the lifespan and, therefore, should be preserved even with older age. This was tested in the present study: Young (18-27 years), middle-aged (39-45 years), and elderly (59-66 years) participants, all without any known cognitive or neurological impairments, performed an auditory duration discrimination task. Interestingly, performance was highly accurate and reaction times were similar for all groups, indicating no differences in auditory duration processing. Task-irrelevant, rare frequency changes were introduced to check whether the participants could detect changes in the environment while focusing on the task-relevant information, and, then could re-focus on the relevant task after distraction. The results showed that the elderly participants had a distraction effect twice the size of the middle-aged group. The event-related brain potentials showed that the mismatch-negativity, P3a, and re-orienting negativity elicited by deviants were present, but later and smaller in elderly participants. These results can be interpreted in terms of central executive processes. While elderly participants are still distractible by changes in the environment when focusing on the task at hand, distractibility is markedly increased. This suggests slower processing of attentional re-allocation towards task relevant information maintained by the working memory system. Noteworthy, is that increased distractibility did not result in a loss of accuracy, suggesting that the processes underpinning attentional allocation are, in general, unimpaired by normal aging.