An open access repository of Middlesex University research http://eprints.mdx.ac.uk Ward, Emma V. and Berry, Christopher J. and Shanks, David R. (2013) An effect of age on implicit memory that is not due to explicit contamination: implications for single and multiple-systems theories.Psychology and Aging, 28 (2 Copyright and moral rights to this thesis/research project are retained by the author and/or other copyright owners. The work is supplied on the understanding that any use for commercial gain is strictly forbidden. A copy may be downloaded for personal, non-commercial, research or study without prior permission and without charge. Any use of the thesis/research project for private study or research must be properly acknowledged with reference to the work's full bibliographic details.This thesis/research project may not be reproduced in any format or medium, or extensive quotations taken from it, or its content changed in any way, without first obtaining permission in writing from the copyright holder(s).If you believe that any material held in the repository infringes copyright law, please contact the Repository Team at Middlesex University via the following email address:The item will be removed from the repository while any claim is being investigated.
AbstractRecognition memory is typically weaker in healthy older relative to young adults, while performance on implicit tests (e.g., repetition priming) is often comparable between groups. Such observations are commonly taken as evidence for independent explicit and implicit memory systems. On a picture version of the continuous identification with recognition (CID-R) task, we found a reliable age-related reduction in recognition memory, while the age effect on priming did not reach statistical significance (Experiment 1). This pattern was consistent with the predictions of a formal single-system model. Experiment 2 replicated these observations using separate priming (CID) and recognition phases, while a combined data analysis revealed a significant effect of age on priming. In Experiment 3 we provide evidence that priming in this task is unaffected by explicit processing, and we conclude that the age difference in priming is unlikely to have been driven by differences in explicit processing between groups of young and older adults ('explicit contamination'). The results support the view that explicit and implicit expressions of memory are driven by a single underlying memory system.Keywords: aging, priming, implicit memory, recognition, explicit contamination Memory can be measured directly or indirectly. Direct or explicit tests (e.g., recognition) require deliberate recollection of specific information from a prior study episode, whereas indirect or implicit tests measure memory of previously studied information in a seemingly unrelated task (e.g., perceptual identification). Priming is a commonly used index of implicit memory. It refers to a long-term change in behavioural response to an item as a result of prior exposure to it, and usually takes ...