Abstract
To examine age-related attentional deficits, young and old observers' Useful Field of View (UFOV) was assessed in focused and divided attention conditions. The UFOV is the region of visual space from which an observer can extract information at any one time. Previous research examining the UFOV has shown that older observers have larger performance deficits than younger observers under divided-attention conditions (Sekuler et al., 2000). The goal of the present study was to examine the time course of these deficits, and any age-related interactions.
In this study observers were presented with 2 tasks: central letter identification and peripheral target localization. The central task required individuals to indicate (4AFC) the identity of a single letter presented at fixation, while the peripheral task required individuals to localize a peripherally presented target. Observers performed each of these tasks either individually (focused attention) or simultaneously (divided attention). The attentional costs (focused — divided attention performance) were assessed for each task, and the time course of these costs was examined by varying stimulus duration.
The results indicate that older adults had more pronounced attentional costs than younger adults for the peripheral task, replicating previous research. In addition, these costs are differentially affected by the amount of processing time made available to observers (i.e., stimulus duration). Whereas peripheral task performance costs declined for younger observers with increasing stimulus duration, these costs persisted for older observers with increasing stimulus duration. These results indicate that younger individuals can overcome initial attentional costs, while older individuals cannot overcome these costs, when provided with additional processing time. The effects of practice and learning on these age-related attentional costs will also be discussed.