The similar effects of verbal and non-verbal intervening tasks on word recall in an elderly population.

Vulnerability to retroactive interference has been shown to increase with cognitive aging. Consistent with the findings of memory and aging literature, the authors of the California Verbal Learning Test-II (CVLT-II) suggest that a non-verbal task be administered during the test's delay interval to minimize the effects of retroactive interference on delayed recall. The goal of the present study was to determine the extent to which retroactive interference caused by non-verbal and verbal intervening tasks affects recall of verbal information in non-demented, older adults. The effects of retroactive interference on recall of words during Long-Delay recall on the California Verbal Learning Test-II (CVLT-II) were evaluated. Participants included 85 adults age 60 and older. During a 20-minute delay interval on the CVLT-II, participants received either a verbal (WAIS-III Vocabulary or Peabody Picture Vocabulary Test-IIIB) or non-verbal (Raven's Standard Progressive Matrices or WAIS-III Block Design) intervening task. Similarly to previous research with young adults (Williams & Donovick, 2008), older adults recalled the same number of words across all groups, regardless of the type of intervening task. These findings suggest that the administration of verbal intervening tasks during the CVLT-II do not elicit more retroactive interference than non-verbal intervening tasks, and thus verbal tasks need not be avoided during the delay interval of the CVLT-II.