Article

Early damage to episodic memory encoding and consolidation
processes has been demonstrated in dementia of the Alzheimer type. However, in
the domain of verbal episodic memory assessment, there are few diagnostic tools
adapted to the old and oldest old as far as ease of administration and accuracy
of normative data are concerned. Classic tasks are either too effortful (like the
free recall/cued recall of 16 items), not sensitive enough
(like the 5 words
test), or insufficiently accurate for people above 70 years old in terms of
normative data. The aim of this study was to develop a reduced task (in
terms of number of items and number of trials) assessing verbal episodic memory
in people aged between 70 and 89 years old. METHODS: The task (GERIA-12) used the
same procedure as the RL/RI-16 task but the list comprised only 12 words and
there were only 2 learning trials. In order to assess consolidation processes, we
included 2 delayed recall trials, one after 20minutes and the other after
24hours. We also calculated indexes adapted from the Item-Specific Deficit
Approach developed by Wright et al., which has the advantage of providing
measures specific to encoding, consolidation and retrieval processes.
Standardization was done with data from 220 people aged between 70 and 89 years
old and belonging to 3 education levels. RESULTS: We obtained a significant
effect of age and education level: scores decrease with age and increase with
education. Norms have thus been calculated taking those two variables into
consideration. Concerning the standardization, Barona method has been used for
free recall scores while percentiles have been used for all other scores (total
recall, free recall, encoding, consolidation and retrieval indexes). Normative
data are also provided for intrusions and perseverations. CONCLUSION: This new
task allows encoding, consolidation and retrieval processes assessment in older
people and has the following advantages: the procedure is more suitable (ease and
time of administration), there are accurate normative data for old and oldest old
people, and there are normative data for two delayed recalls (at 20minutes and at
24hours).
CI - Copyright (c) 2015 Elsevier Masson SAS. All rights reserved.

Langue : FRANCAIS