Age-related differences in neural activity during item and temporal-order memory retrieval: a positron emission tomography study.

Published

Journal Article

Positron emission tomography (PET) was used to investigate the hypothesis that older adults' difficulties with temporal-order memory are related to deficits in frontal function. Young (mean 24.7 years) and old (mean 68.6 years) participants studied a list of words, and were then scanned while retrieving information about what words were in the list (item retrieval) or when they occurred within the list (temporal-order retrieval). There were three main results. First, whereas the younger adults engaged right prefrontal regions more during temporal-order retrieval than during item retrieval, the older adults did not. This result is consistent with the hypothesis that context memory deficits in older adults are due to frontal dysfunction. Second, ventromedial temporal activity during item memory was relatively unaffected by aging. This finding concurs with evidence that item memory is relatively preserved in old adults and with the notion that medial temporal regions are involved in automatic retrieval operations. Finally, replicating the result of a previous study (Cabeza, R., Grady, C. L., Nyberg, L., McIntosh, A. R. , Tulving, E., Kapur, S., Jennings, J. M., Houle, S., and Craik, F. I. M., 1997), the old adults showed weaker activations than the young adults in the right prefrontal cortex but stronger activations in the left prefrontal cortex. The age-related increase in left prefrontal activity may be interpreted as compensatory. Taken together, the results suggest that age-related changes in brain activity are rather process- and region-specific, and that they involve increases as well as decreases in neural activity.

Full Text

Duke Authors

Cited Authors

  • Cabeza, R; Anderson, ND; Houle, S; Mangels, JA; Nyberg, L

Published Date

  • January 2000

Published In

Volume / Issue

  • 12 / 1

Start / End Page

  • 197 - 206

PubMed ID

  • 10769316

Pubmed Central ID

  • 10769316

Electronic International Standard Serial Number (EISSN)

  • 1530-8898

International Standard Serial Number (ISSN)

  • 0898-929X

Digital Object Identifier (DOI)

  • 10.1162/089892900561832

Language

  • eng