Mental imagery training in older adults: Which are benefits and individual predictors?

Strategic memory training involves explicit instructions in mnemonic methods to improve recall. Mental imagery is considered among the most effective encoding strategies. The aim of the present study was to assess the benefits of a strategic memory training based on mental imagery (originally proposed by Carretti et al., 2007) and to further investigate its potentials. The study represents a replication in a new and independent cultural setting and features valuable methodological amendments, while it also examines individual predictors of training efficacy.

A sample of 91 older volunteers (age 61-88), divided in training and control group, participated in the training. Specific training gain in the immediate word list recall (criterion task), as well as transfer effects on Letter-Number Sequencing (working memory [WM] task), long-term recall and recognition (LTM tasks) were tested at the pretest and at the posttest.

Analysis of variance showed posttraining effects in immediate word recall and long-term verbal recall, but no effects in WM task and long-term recognition. Regression analysis showed age to be the only significant predictor in one task, the immediate word recall.

Overall, proposed training can improve some aspects of memory performance by aiding in strategic use of mental imagery. Transfer to other tasks and contribution of individual predictors to training efficacy results limited, however. It seems that training benefits are evident when task similarity enables transfer-appropriate processing (as evidenced in gains of both recall tasks), while training efficacy relies on individual characteristics which contribute to the execution of some task components.