ABSTRACT
A total of 16 young (M = 27.25 years), 13 healthy elderly (M = 75.38 years), and 10 older adults with probable mild cognitive impairment (MCI; M = 78.6 years) carried out a task under two different encoding conditions (shallow vs. semantic) and two retrieval conditions (free recall vs. recognition). For the shallow condition, participants had to decide whether the first or last letter of each word in a list was "E." For the semantic condition, they had to decide whether each word represented a concrete or abstract entity. The MCI group was only able to benefit from semantic encoding to the same extent as the healthy older adults in the recognition task, whereas the younger and healthy older adults benefited in both retrieval tasks. These results suggest that the MCI group required cognitive support at retrieval to make effective use of semantic processing carried out at encoding. In the discussion, we suggest that adults with MCI engage more in deep processing, using the semantic network, than hitherto thought.
Subject(s)
Aging/physiology , Cognition Disorders/physiopathology , Discrimination, Psychological/physiology , Mental Recall/physiology , Recognition, Psychology/physiology , Adult , Aged , Aged, 80 and over , Analysis of Variance , Female , Humans , Male , Neuropsychological Tests , Pattern Recognition, Visual , Psychometrics , Reaction Time/physiology , Semantics , Young AdultABSTRACT
The aim of this study was to evaluate the effect of aging on the storage of visual and spatial working memory according to Logie's model of working memory (1995). In a first experiment young, elderly, and very old subjects carried out two tasks usually used to measure visual span (Visual Patterns Test) and spatial span (Corsi Block Tapping test). In the second experiment, we modified the encoding time of the Visual Patterns Test so that it was the same as in the Corsi Block Tapping test. Results indicate that the visual span decreases more with advanced age than the spatial span, even when the encoding time between the Visual Patterns Test and the Corsi Block Tapping test is controlled. These results support the fractionation of the visuo-spatial working memory and show that the more pronounced age-related effect on the visual span is robust and independent of the encoding time.
