Publications by authors named "Shannon Robertson"

The current study examined the effects of responses on error-adjacent trials (i.e., those immediately preceding or following errors) on age differences in measures of intraindividual variability and the shape of response time (RT) distributions on a two-back task.

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It has been suggested that older adults are more variable in their performance because they are more prone to lapses of either attention or intention. In the present experiment, 9 young and 9 older adults each performed nearly 2000 trials of a same-different judgment task. As expected, older adults were slower and more variable than young adults.

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It has been suggested, primarily based on response time (RT) data, that there is an age-related increase in intraindividual variability. To determine whether older adults show more intraindividual variability in working memory (WM) performance, we had younger and older adults perform three verbal WM tasks of varying complexity as well as a same-different judgment RT task. For both groups, individual performance tended to be more variable on the two complex span tasks than on the simple span task.

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Much recent research using discrete unimanual tasks has indicated that individuals with Down syndrome (DS) have more difficulty performing verbal-motor tasks as compared to visual-motor tasks (see Perceptual-Motor Behavior in Down Syndrome, Human Kinetics, Champaign, IL, 2000, p. 305 for a review). In continuous tasks, however, individuals with DS perform better when movement is guided by auditory information compared to visual information (Downs Syndr.

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