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List learning tests are used in practice for diagnosis and in research to characterize episodic memory, but often suffer from ceiling effects in unimpaired individuals. We developed the Modified Rey Auditory Verbal Learning Test, or ModRey, an episodic memory test for use in normal and preclinical populations. We administered the ModRey to 230 healthy adults and to 86 of the same individuals 102 days later and examined psychometric properties and effects of demographic factors. Primary measures were normally distributed without evidence of ceiling effect. Differences between alternate forms were of very small magnitude and not significant. Test–retest reliability was good. Higher participant age and lower participant education was associated with poorer performance across most outcome measures. We conclude that the ModRey is appropriate for episodic memory characterization in normal populations and could be used as an outcome measure in studies involving preclinical populations.

Alzheimer's disease is defined by abnormal levels of amyloid and tau biomarkers. Even cognitively normal older adults with clinically relevant amyloid and tau levels perform worse on memory tests. However, it is unclear if the relationship between biomarker level and memory extends below clinical thresholds. We hypothesized that even subclinical biomarker levels are associated with memory when measured with neuropsychological tests designed to detect dysfunction in preclinical disease states. In a group of cognitively normal, “biomarker-negative” older men and women, we investigated the relationship between cerebrospinal fluid biomarker levels and memory measured with the ModRey, a list-learning task designed to assess memory in preclinical and cognitively normal adults. Cerebrospinal amyloid levels were associated with ModRey memory retention, the proportion of information retained after a delay period. When older adults with mild impairment were included, cerebrospinal fluid tau levels were also associated with ModRey retention. The association of amyloid and tau levels with memory was independent of each other. These results suggest cognitive changes associated with Alzheimer's disease pathology might occur earlier than currently thought.

Socioeconomic status (SES) predicts health, wellbeing, and cognitive ability, including executive function (EF). A body of recent work has shown that childhood SES is positively related to EF, but it is not known whether this disparity grows, diminishes or holds steady over development, from childhood through adulthood. We examined the association between childhood SES and EF in a sample ranging from 9–25 years of age, with six canonical EF tasks. Analyzing all of the tasks together and in functionally defined groups, we found positive relations between SES and EF, and the relations did not vary by age. Analyzing the tasks separately, SES was positively associated with performance in some but not all EF measures, depending on the covariates used, again without varying by age. These results add to a growing body of evidence that childhood SES is associated with EF abilities, and contribute novel evidence concerning the persistence of this association into early adulthood.

White matter hyperintensities (WMHs) have been linked to cognitive dysfunction and dementia, although the reasons are unclear. One possibility is that WMHs promote neurodegeneration, which, in turn, affects cognition. We examined whether cortical thickness, a marker of neurodegeneration, mediates the relationship between WMHs and cognition among 519 older adults. Using conditional process analysis modeling techniques, we examined the association between WMH volume and global cognition and tested whether cortical thickness mediates this relationship statistically. We also tested specific regional hypotheses to determine whether cortical thickness or volume in the medial temporal lobe mediates the relationship between WMH volume and memory. Increased total WMH volume was associated with poorer global cognition and memory. The mediating effects were present across all cognitive domains. Global cortical thickness and medial temporal lobe thickness/volume mediated the relationship of WMH volume on global cognition and memory functioning. The mediating relationship was similar across racial and ethnic groups or across diagnostic groups (i.e., mild cognitive impairment/Alzheimer’s disease). The findings suggest that WMHs promote atrophy, which, in turn, drives cognitive decline and highlight a potential pathway in which small vessel cerebrovascular disease affects cognition by promoting neurodegenerative changes directly.

Background/Study Context: Magnetic resonance imaging (MRI) markers of cerebrovascular disease and atrophy are common in older adults and are associated with cognitive and medical burden. However, the extent to which they are related to health care expenditures has not been examined. We studied whether increased Medicare expenditures were associated with brain markers of atrophy and cerebrovascular disease in older adults.MethodsA subset of participants (n=592; mean age=80 years; 66% women) from the Washington Heights Inwood Columbia Aging Project (WHICAP), a community-based observational study of aging in upper Manhattan, received high-resolution MRI and had Medicare expenditure data on file. We examined the relationship of common markers of cerebrovascular disease (i.e., white matter hyperintensities and presence of infarcts) and atrophy (i.e., whole brain and hippocampal volume) with Medicare expenditure data averaged over a 10-year period. Main outcome measures were (a) mean Medicare payment per year across the 10-year interval; (b) mean payment for outpatient care per year; and (c) mean payment for inpatient care per year of visit. In addition, we calculated the ratio of mean inpatient spending to mean outpatient spending as well as the ratio of mean inpatient spending to mean total Medicare spending.ResultsIncreased Medicare spending was associated with higher white matter hyperintensity volume, presence of cerebral infarcts, and smaller total brain volume. When examining specific components of Medicare expenditures, we found that inpatient spending was strongly associated with white matter hyperintensity volume and that increased ratios of inpatient to outpatient and inpatient to total spending were associated with infarcts.ConclusionMedicare costs are related to common markers of "silent" cerebrovascular disease and atrophy.