The memory binding test in a longitudinal study of cognitive aging and preclinical disease

The Memory Binding Test (MBT) shows promise in detecting early cognitive changes associated with Alzheimer's disease (AD). This study assesses the psychometric properties (i.e., construct and criterion validity, test-retest reliability) of the MBT and its sensitivity to incipient disease and incident cognitive impairment.

One hundred forty-nine cognitively unimpaired adults ages 45-85 completed the MBT and neuropsychological tests at baseline; 132 returned for 2-year follow-up. Based on neuroradiological ratings of amyloid positron emission tomography and MRI markers at baseline, they were categorized as healthy (n = 94) or having preclinical disease (n = 55, either on the AD continuum or having non-AD pathologic change). Construct validity was assessed by the associations between MBT scores, demographics, and neuropsychological scores within the healthy group. Criterion validity was assessed by testing how MBT scores correlate with AD biomarkers, differ and discriminate between groups at baseline, and predict incident cognitive impairment.

MBT scores decreased with age and were strongly associated with memory and global cognition. MBT scores were largely not associated with amyloid, hippocampal volume, or AD signature cortical volume but related to white matter lesion volume in those with preclinical disease. The preclinical groups performed worse on MBT immediate free recall at baseline than the healthy group, but no scores predicted incident cognitive impairment at follow-up. Most scores demonstrated modest test-retest reliability.

This study demonstrates that the MBT has adequate construct validity in cognitively unimpaired adults, moderate sensitivity to preclinical disease cross-sectionally, and limited prognostic utility. Careful consideration of demographic influences on score interpretation remains necessary. (PsycInfo Database Record (c) 2024 APA, all rights reserved).