A Brief Computerized Paired Associate Test for the Detection of Mild Cognitive Impairment in Community-Dwelling Older Adults

Abstract

Background: Semantic memory interference has been found to be a predictive cognitive marker of incipient AD. This is relevant given that developing novel paradigms to identify subtle cognitive and functional deficits is a priority in preclinical Alzheimer's disease research. Objective: To examine the utility of a novel computerized paired associate test in distinguishing between mild cognitive impairment (MCI) and cognitively normal (CN) groups of older adults residing in the community. Methods: Participants that were CN (n = 64) or MCI (n = 34) were administered the Miami Test of Semantic Interference and Learning (MITSI-L). This novel instrument is a brief, computerized paired associate test that measured the strength of memory binding of semantically related word pairs and introduced a proactive semantic interference condition which required participants to make different associations between semantically similar targets. A series of ANOVAs explored differences on MITSI-L performance. Logistic regression and receiver operator curves (ROC) analyses were employed to further determine discriminative validity. Results: MCI participants had lower scores on all indices relative to CN elders. A composite of two subscores correctly classified 85.3 of MCI and 84.4 of CN participants. Area under the ROC was higher relative to the MMSE, immediate memory for passages, and several subtests of a sensitive memory measure, the LASSI-L. Conclusions: The MITSI-L is a computerized test that can successfully differentiate MCI from CN participants. Area under the ROC curve exceeded that of global mental status and other memory measures. The effectiveness of the MITSI-L in detecting MCI, and its brief administration and portability render it worthy of further research.