Medial Temporal Lobe Correlates of Memory Screening Measures in Normal Aging, MCI, and AD

Unlabelled: This article aimed to study the correlations for both the Memory Impairment Screen (MIS) and the Free and Cued Selective Reminding Test (FCSRT) with regard to the volumetric measures of hippocampal formation and entorhinal cortex and to explore the effect size of these measures.

Methods: A total of 34 healthy controls, 24 participants with mild cognitive impairment (MCI), and 20 mild-to-moderate-staged Alzheimer disease (AD) participants underwent neuropsychological testing and magnetic resonance imaging (MRI). Global volumetric measures were obtained and hippocampal and entorhinal volumes were calculated. Spearman correlations were calculated between memory scores and brain volumes and an effect size analysis was performed.

Results: No significant correlations with global brain volumes were found. There were dissimilar correlations among groups regarding memory and hippocampal and entorhinal volumes. No significant relationships were observed in healthy controls. The MCI group reached the higher correlation indexes, up to r = .55. In AD, only one significant correlation was observed between the delayed score of the FCSRT and the left hippocampus. Effect size values were higher for memory tests than for MRI measures, reaching d = 4.3 for the delayed score of the FCSRT.

Conclusions: Although the MIS did not reach the strong results of the FCSRT, it demonstrated a similar pattern to the FCSRT in correlational analysis. These results support the validity and usefulness of the MIS despite its brevity of application. Memory testing showed better discrimination among healthy controls, MCI, and AD participants than MRI measures by means of effect size analysis.