Age-related changes in regional cerebral blood flow associated with item and temporal-order memory retrieval

Young and older adults studied a word list and were then PET scanned while retrieving information about what words were in the list (item retrieval) or when words occurred within the list (temporal-order retrieval). There were three main findings. First, younger but not older adults engaged right prefrontal regions more during temporal-order retrieval than during item retrieval. This result is consistent with the hypothesis that context memory deficits in older adults are due to frontal dysfunction. Second, ventromedial activity during item retrieval was relatively unaffected by aging. This result concurs with the hypothesis that automatic retrieval operations mediated by the medial temporal lobes are spared by aging. Third, older adults showed weaker activations than young adults in the right prefrontal cortex, but showed stronger activations in the left prefrontal cortex. This last result may be interpreted as evidence for functional compensation in older adults. © 1999 Academic Press.

Duke Scholars

Author Roberto Cabeza Psychology & Neuroscience