Study of attentional networks in older and young people
ZHOU Shan-Shan, WANG Kai, WANG Chang-Qing, MENG Yu, FAN Jin. Department of Neurology, The Affiliated Hospital, Anhui Medical University, Hefei 230022, China
Objective Previous studies suggest that aging has been associated with impairmnt in attention. Posner and Petersen (1990) proposed that the sources of attention form a specific system of anatomical areas, which can be further broken down into three networks. These networks carry out the functions of alerting, orienting, and executive control. Reaction time measures can be used to quantify the processing efficiency within each of these three networks. However, it is not known whether this is a global attentional deficit or relates to a specific attentional network. The study was designed to estimate the influence of aging on the attention networks in Chinese older and younger adults.Methods This study used the attention network test to compare older with young adults on the efficiency of three anatomically defined attentional networks: alerting, orienting, and executive control.Results Older adults showed a highly significant deficit in the executive network and a smaller but significant deficit alerting networks. The data showed that the older group took longer to resolve conflict than the young (z=-3.992, P0.01, Mann-Whitney U). Older participants were significantly worse than the young people in maintaining the alert state tonically and the phasic response to a warning signal (t (58)=2.77,P0.05). The independent sample t test showed that the older group performed significantly slowly than the young group (t (58)=-9.61, P0.01). There was no deficit in the orienting network between the young and the older people. Conclusions Aging leads to deficits of the alerting and executive networks, but is irrelated to the orienting network. The executive attention has been shown in normal subjects to active the anterior cingulate and lateral prefrontal areas. Age-related deterioration in the prefrontal lobe and the dopaminergic system may explain the age-related changes in executive and alerting attentional networks.