Remembering the Past and Foreseeing the Future while Dealing with the Present: A Comparison of Young Adult and Elderly Cohorts on a Multitask Simulation of Occupational Activities

Abstract

Thirty-five young adult and 38 elderly cybernauts, matched for education, sex, alcohol consumption, and time/day of computer use were compared on a computerized simulation of professional activities of daily living (ADLs). The program quantified performance in terms of speed and accuracy on four major constructs: (1) planning (a 30-item office party script); (2) prospective memory (injections, sleep, phone); (3) working memory (PASAT, D2, and CES analogs); and (4) retrospective memory. Participants had to organize an office party, self inject insulin and go to bed at requisite times of day, do "office work" at unpredictable times of day, and answer the phone that blinked but did not ring (near threshold stimulus). The elderly were markedly and equally impaired on all four constructs (F = 24.3, p < .000). The elderly were also equally and markedly impaired on slave and central executive systems (c.f. Baddeley's model) and on event-based and time-based prospective memory (c.f. McDaniel's model)-findings arguing against a "frontal" model of cognitive decline. This supports Salthouse's concept of a "general factors" decline in normal aging due to diffuse deterioration of the brain. On the other hand, as expected from previous findings, the balance of omissiveness/commissiveness was significantly increased in the elderly sample's error profile. Furthermore, the balance of speed and accuracy was significantly increased in the elderly. This defines limits of the "general factors" model. The elderly also markedly underused a clock icon which had to be clicked on to get the virtual time of day necessary for integrating all the required actions. Prospective memory explained 11% of the aging variance despite partialing out of the three other constructs, making it appear as a golden standard of sensititivity to normal aging-though perhaps provided it be implemented in a distracting, multitask, strategically demanding context.

Post unilateral lesion response biases modulate memory: Crossed double dissociation of hemispheric specialisations

“…At the very least, the effect of age would have to be partialed out of the main test of the central hypothesis. Second, Guimond et al (2006) and Aylward, Brager, and Harper (2002) have found that normal ageing is characterised by a significant shift towards omissiveness over commissiveness on memory tests and other cognitive tests. Thus again, ageing could bias the results of the current study by contributing noise, or even a nefarious bias to the test of our main hypothesis (the interaction between type of memory disturbance and lesion side).…”

“…There are two reasons why the difference between middle-age and elderliness might be relevant to the types of memory dysfunction investigated here. First, memory impairment is one of the most radical cognitive manifestations of ageing in the general population (Guimond, Braun, Rouleau, & Godbout, 2006). It can therefore be imagined that amnesic symptoms, more than commissive symptoms, could be related to advancing age, adding variance to the effect of unilateral lesions and complicating interpretation of the effect of lesions in the present database.…”

Evidence from unilateral lesions of early uncompensable implementation of opposed response-biases in each hemisphere of the brain

“…However, though the effect was in the predicted direction in the left-lesioned group, in the present investigation it was far from significance. For details of the Lesionside × Response-bias interaction, subtask by subtask on RLASv10, see Guimond's (2011) PhD thesis [53].…”

“…The research tool designed for the present experiment was a multitask occupational computer simula-tion called RLAS, which has been shown to be highly reflective of cognitive decline related to normal aging [53] and to brain lesions [52]. It generates normally distributed performances devoid of ceiling effects [54].…”

Forgetfulness and older adults: concept analysis

“…occasionally forgetting to keep an appointment) become more prevalent (Bä ckman et al 2004, Guimond et al 2006. Kliegel and Jä ger (2006) examined prospective and working memory among four age-groupings (n = 127), separating older adults by 10-year groupings from age 60 to 91 years; the data derived were then compared to those from a group of younger people ranging from age 22 to 31 years.…”