Preliminary Validation of the Learning Ratio for the HVLT-R and BVMT-R in Older Adults.

BACKGROUND: The learning slope is typically represented as the raw difference between the final score and the score of the first learning trial. A new method for calculating the learning slope, the learning ratio (LR), was recently developed; it is typically represented as the number of items that are learned after the first trial divided by the number of items that are yet to be learned. OBJECTIVE: To evaluate the convergent and criterion validity of the LR in order to understand its sensitivity to Alzheimer disease (AD) pathology. METHOD: Fifty-six patients from a memory clinic underwent standard neuropsychological assessment and quantitative brain imaging. LR scores were calculated from the Hopkins Verbal Learning Test-Revised and the Brief Visuospatial Memory Test-Revised and were compared with both standard memory measures and total hippocampal volumes, as well as between individuals with AD and those with mild cognitive impairment. RESULTS: Lower LR scores were consistently associated with poorer performances on standard memory measures and smaller total hippocampal volumes, generally more so than traditional learning slope scores. The LR scores of the AD group were smaller than those of the group with mild cognitive impairment. Furthermore, the aggregation of LR scores into a single metric was partially supported. CONCLUSION: The LR is sensitive to AD pathology along the AD continuum. This result supports previous claims that the LR score can reflect learning capacity better than traditional learning calculations can by considering the amount of information that is learned at trial 1.

Examining the Relationship between a Verbal Incidental Learning Measure from the WAIS-IV and Neuroimaging Biomarkers for Alzheimer's Pathology.

Convergent validation of a verbal incidental learning (IL) task from the WAIS-IV using neuroimaging biomarkers is warranted to understand its sensitivity to Alzheimer's disease (AD) pathology. Fifty-five memory clinic patients aged 59 to 87 years received neuropsychological assessment, and measures of IL and quantitative brain imaging. Worse IL-Total Score and IL-Similarities performances were significantly associated with smaller hemispheric hippocampal volumes. IL measures were not significantly correlated with cerebral ß-amyloid burden, though a trend was present and effect sizes were mild. These hippocampal volume results suggest that this IL task may be sensitive to AD pathology along the AD continuum.

Validity of a verbal incidental learning measure from the WAIS-IV in older adults.

Incidental memory may reflect a form of learning in everyday life, although it is not consistently evaluated during standard neuropsychological evaluations. Further validation of a recently created measure of verbal Incidental Learning (IL) from the Wechsler Adult Intelligence Scale-IV is necessary to understand the utility of such a measure in clinical settings. Sixty-eight adults aged 50 to 89 were recruited from a Cognitive Disorders Clinic while receiving a standard neuropsychological assessment, along with two additional measures of IL. IL-Total Score was significantly correlated with immediate and delayed memory trials from standard neuropsychological tests (rs = .43 to .73, ps < .001, ds = 0.94-2.14), with worse IL performance being associated with lower memory abilities. Participants with probable Alzheimer's disease performed worse on the IL-Total Score than participants with Mild Cognitive Impairment, t(39.997) = 5.46, p < .001, d = 1.13. Given the strong relationships between this IL task and traditional memory measures in our sample, and the discrimination of IL-Total Score performance among diagnostic groups despite its short administration time, this IL task may play a role as a measure of memory in brief cognitive evaluations.