A New Scale for the Evaluation of Proactive and Retroactive Interference in Mild Cognitive Impairment and Early Alzheimer’s Disease

Abstract

Objective: The authors evaluated the psychometric properties and clinical utility of the Loewenstein-Acevedo Scale for Semantic Interference and Learning (LASSI-L), in patients with amnestic Mild Cognitive Impairment (aMCI) and early Alzheimer’s disease (AD). Methods: Subjects were administered Target List A and instructed to remember 15 common words belonging to a specific semantic category, using multi-modal, active encoding procedures. After free recall and cued recall trials of the target list, a second learning trial was offered, followed by a cued recall trial, to facilitate the initial acquisition of targets. Thereafter, the subject was exposed to a semantically-related List B, which was administered in the same manner as Target List A. Test-retest reliability, concurrent and discriminative validity were assessed. LASSI-L measures were then correlated with Magnetic Resonance Imaging (MRI) measurements of medial temporal lobe atrophy (MTA). Results: High test-retest, concurrent and discriminative validity was obtained for LASSI-L subscales, and MTA atrophy scores were highly and negatively correlated with LASSI-L indices. Conclusion: Subtests of the LASSI-L demonstrate high reliability and validity, and are strongly associated with MRI biomarkers of early neurodegenerative disease. It is concluded that the LASSI-L is a highly promising test for the assessment of mild cognitive impairment and early AD among the elderly. Keywords: