Breaking down unitization: Is the whole greater than the sum of its parts?
Memory impairments are often observed in aging. Specifically, older adults have difficulty binding together disparate elements (relational memory). We have recently shown that a cognitive strategy known as unitization can mitigate impaired relational learning in the transverse patterning task (TP) in both amnesia and healthy aging. This strategy allows items to be fused together through an interaction such that one item acts upon another. In the context of TP, unitization is comprised of three component processes: (1) fusion, (2) motion, and (3) semantic comprehension of action/consequence sequences. Here, we examine which of these components are sufficient to mitigate age-related impairments. Four groups of older adults were given either the full unitization strategy or one of the three component strategies. Each group of older adults showed impairments in memory for the relations among items under standard training instructions relative to a threshold that marks learning of a winner-take-all rule (elemental threshold). However, participants who were given either the full unitization strategy or the action/consequence-only strategy showed improved performance, which was maintained following the 1-hour delay. Therefore, semantically rich action/consequence interactions are sufficient to mitigate age-related relational memory impairments.
KeywordsMemory Aging Unitization Fusion Semantic comprehension
This research was supported in part by a postdoctoral fellowship from the Canadian Institutes of Health Research (CIHR) awarded to M.C.D. as well as support from the Ontario Ministry of Health and Long Term Care through the Ontario Research Coalition of Research Institutes/Centres on Health & Aging (ORC) to M.C.D. This work was also supported by CIHR Operating Grants awarded to J.D.R. (No. MOP-126003) and M.D.B. (No. MOP-115148), and by Tier II Canada Research Chair Awards awarded to J.D.R. and M.D.B. The authors state that they do not have any conflicts of interest to declare.
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