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D E Kieras

Publications and source records attributed to D E Kieras.

5 recordsLinked to original sources
PubMed2001

Virtually perfect time sharing in dual-task performance: uncorking the central cognitive bottleneck.

A fundamental issue for psychological science concerns the extent to which people can simultaneously perform two perceptual-motor tasks. Some theorists have hypothesized that such dual-task performance is severely and persistently constrained by a central cognitive "bottle-neck," whereas others have hypothesized that skilled procedural decision making and response selection for two or more tasks can proceed at the same time under adaptive executive control. The three experiments reported here support this latter hypothesis. Their results show that after relatively modest amounts of practice, at least some participants achieve virtually perfect time sharing in the dual-task performance of basic choice reaction tasks. The results also show that observed interference between tasks can be modulated by instructions about differential task priorities and personal preferences for daring (concurrent) or cautious (successive) scheduling of tasks. Given this outcome, future research should investigate exactly when and how such sophisticated skills in dual-task performance are acquired.

Adult↗
PubMed2000

Aging and the psychological refractory period: task-coordination strategies in young and old adults.

The apparently deleterious effect of aging on dual-task performance is well established, but there is little agreement about the source of this effect. Studies of the psychological refractory period (PRP) indicate that young adults can flexibly control dual-task performance through task-coordination strategies. Thus, the performance of older adults might differ from young adults because older adults use different task-coordination strategies. To test this hypothesis, the executive-process interactive control (EPIC) architecture was applied to quantify the reaction time data from two PRP experiments conducted with young (age 18-26) and older (age 60-70) adults. The results show that participants' ability to coordinate the processing of two tasks did not decline with age. However, dual-task time costs were greater in the older adults. Three sources for this increase were found: generalized slowing, process-specific slowing, and the use of more cautious task-coordination strategies by the older adults.

Adult↗
PubMed1997

A computational theory of executive cognitive processes and multiple-task performance: Part 1. Basic mechanisms.

A new theoretical framework, executive-process interactive control (EPIC), is introduced for characterizing human performance of concurrent perceptual-motor and cognitive tasks. On the basis of EPIC, computational models may be formulated to simulate multiple-task performance under a variety of circumstances. These models account well for reaction-time data from representative situations such as the psychological refractory-period procedure. EPIC's goodness of fit supports several key conclusions: (a) At a cognitive level, people can apply distinct sets of production rules simultaneously for executing the procedures of multiple tasks; (b) people's capacity to process information at "peripheral" perceptual-motor levels is limited; (c) to cope with such limits and to satisfy task priorities, flexible scheduling strategies are used; and (d) these strategies are mediated by executive cognitive processes that coordinate concurrent tasks adaptively.

Attention↗