Names and numberplates: Quasi-everyday associative memory tasks for distinguishing amnestic mild cognitive impairment from healthy aging

Abstract

Amnestic mild cognitive impairment (aMCI) delineates a population at high risk for subsequently developing Alzheimer's disease (AD)—that is, people with preclinical AD. Associative episodic memory tasks are particularly sensitive to preclinical AD; however, they often lack ecological validity, which is important when evaluating performance in daily activities. We describe the development of two quasi-everyday associative memory tasks—the La Trobe Face–Name test and the La Trobe Numberplate task—and their utility in profiling and separating 70 aMCI participants from 101 healthy older adults (HOA) compared with standard episodic memory tasks. aMCI participants performed significantly worse overall and demonstrated a greater forgetting rate than HOA on both tasks. The everyday tasks separated aMCI from HOA participants as effectively as standard episodic memory tasks and were well tolerated. These tasks provide a valuable addition to neuropsychologists' toolkits with enhanced ecological (verisimilitude) and face validity for assisting in counseling clients, measuring the effect of interventions, and profiling everyday memory performance in HOA and aMCI.

Keywords:

• Mild cognitive impairment
• Aging
• Everyday memory
• Ecological validity
• Associative memory

Acknowledgments

We would like to thank the Cognitive Dementia and Memory Services (CDAMS) at Caulfield Hospital, Melbourne Health, Austin Health, St. George's Hospital, Wantirna Hospital, Barwon Health, and Bendigo Health for referring participants with amnestic mild cognitive impairment to the study and for allowing the use of their facilities. We would also like to thank Michael Woodward, Alasdair Mander, and Bundoora Extended Care Centre CDAMS for patient referrals. Thanks to Sarah Price, Nadia Petruccelli, and Fenny Muliadi for their assistance with coordination of the study, recruitment, and data management, and to the numerous research assessors assisting with data collection. This research received funding from a National Health and Medical Research Council of Australia grant. Kerryn Pike is funded by a National Health and Medical Research Council of Australia Clinical Research Fellowship. The authors have no conflict of interest. Further information about the stimuli for the novel tasks can be obtained from the first author: [email protected]

Notes

¹If only one of the memory performances was below criterion, in an otherwise normal performance, an alternative version was administered, and if at or above –1.5 standard deviations of the mean for age norms for delayed recall of that test, the healthy older adult was included. This criterion was used as it is generally recognized that in healthy populations of older people, a single low performance is not uncommon in an otherwise normal performance across multiple tests (Iversen, 2006; Palmer, Boone, Lesser, & Wohl, 1998; Rotrou et al., 2005).