Effects of environmental support and strategy training on older adults' use of context.

Abstract

Age-related cognitive differences may be due, in part, to difficulties using task-relevant context in a proactive manner. Two studies evaluated different methods for increasing older adults' use of context in the AX-Continuous Performance Task (H. E. Rosvold, A. F. Mirsky, I. Sarason, E. D. Bransome, & L. H. Beck, 1956), which evaluates components of context processing. The results suggest that (a) age differences in the use of context are not due to reduced access to cue information, (b) directed strategy training made older adults' context processing performance more like that of young adults, and (c) similar performance changes could be observed with less directed instruction and extended practice. These results suggest that age-related differences in context processing can be ameliorated by directed strategy training or extended practice.

Flexible neural mechanisms of cognitive control within human prefrontal cortex

“…1). These imaging-based age differences are consistent with prior behavioral studies, in which older adults exhibited smaller cue-based expectancy effects but also larger probe-related interference effects than younger adults (7)(8)(9).…”

“…We interpret this effect similarly to other researchers (20-23)-namely, that an age-related impairment in goal maintenance abilities led to a compensatory shift in cognitive strategy, which we suggest involves reactive control. However, our findings also suggest that such goal maintenance deficits are not fixed and immutable, but might instead be ameliorated by focused training (9). Specifically, we showed that age-related differences in the activation dynamics of lateral PFC during AX-CPT performance can be normalized through direct instruction of cognitive control strategy.…”

“…A task paradigm that has been frequently used to examine the underlying mechanisms of cognitive control is the AX version of the Continuous Performance Test, or AX-CPT (7)(8)(9)(10)(11)(12)(13)(14)(15). This task is thought to measure goal representation, maintenance, and updating.…”

“…Active maintenance of this frequently updated task goal information is required to bridge the delay between cue and probe presentation. In a series of behavioral studies, it has been shown that the AX-CPT task provides sensitive and specific indices of cognitive control function (7)(8)(9). Likewise, neuroimaging studies have reliably demonstrated the presence of lateral PFC activity related to the active maintenance of task goals during AX-CPT performance (10)(11)(12)(13)(14)(15).…”

“…Different experimental manipulations were used for each group. For older adults, we attempted to promote proactive control by providing focused cognitive training in the AX-CPT task, using an instructional protocol that was successful in a prior behavioral study (9). Conversely, in younger adults, we tested whether we could promote reactive control through a penalty incentive manipulation that increased attention to the probe (potentially at the expense of the cue).…”