Ageing and implicit learning: explorations in contextual cuing.
Doctoral thesis, UCL (University College London).
Research in cognitive ageing has found that while older adults show reductions in performance on standard explicit memory tasks, implicit memory performance remains relatively stable. Such findings are often used to support the popular dual-systems account of human learning and memory, which organizes these types of cognition into distinct implicit and explicit systems. In contrast to previous studies, we found that healthy older adults show learning impairments on an implicit contextual cuing task when compared to younger adults, in addition to expected poor performance on an explicit generation test. To examine the possibility that slower overall response speed may account for the implicit deficit, younger adults’ response times were artificially increased by altering the display properties so as to match those of older adults. Learning in younger participants remained intact under these conditions. Similarly, when display properties were altered to produce faster responses in older participants, their learning continued to be impaired. These results reveal that implicit processing is not immune to the effects of ageing, and that these deficits cannot be attributed solely to older adults’ slower overall response speed. In a further series of experiments using younger participants, we examined the claim that implicit knowledge is not accessible to awareness in contextual cuing. When the number of trials used in an explicit generation test was increased, we found that contextual cuing information was consciously retrievable. These results suggest that the shorter tests used previously were not statistically powerful enough to detect a true effect. Furthermore, when concurrent implicit and explicit tests were used, learning did not precede awareness. Collectively, these findings suggest that awareness may be a necessary concomitant of contextual cuing in older adults, and provide further evidence that learning and memory should not be divided on the basis of consciousness.
|Title:||Ageing and implicit learning: explorations in contextual cuing|
|Open access status:||An open access version is available from UCL Discovery|
|UCL classification:||UCL > School of Life and Medical Sciences > Faculty of Brain Sciences > Psychology and Language Sciences (Division of) > Experimental Psychology|
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