Asenath LaRue

Low cerebral blood flow is associated with lower memory function in metabolic syndrome

Metabolic syndrome (MetS)—a cluster of cardiovascular risk factors—is linked with cognitive decline and dementia. However, the brain changes underlying this link are presently unknown. In this study, we tested the relationship between MetS, cerebral blood flow (CBF), white matter hyperintensity burden, and gray matter (GM) volume in cognitively healthy late middle‐aged adults. Additionally, the extent to which MetS was associated with cognitive performance was assessed.

The occurrence of different intrusive errors in patients with Alzheimer's disease, multiple cerebral infarctions, and major depression

Recent evidence suggests that specific types of intrusive errors may occur more often in the protocols of Alzheimers disease (AD) patients than in those of patients diagnosed with other types of dementia. Using the FULD Object Memory Evaluation, we documented the occurrence of five qualitatively different types of intrusive errors for mildly and moderately impaired patients with AD and multiple cerebral infarctions (MCI). Depressed and normal elderly controls were also studied. Despite an equivalent degree of impairment on a broad array of neuropsychological measures, mildly impaired AD patients evidenced greater deficits on a measure tapping retrieval from semantic memory and demonstrated a higher occurrence of specific types of intrusive errors relative to their mildly impaired MCI counterparts. Further, both of these measures were highly correlated, suggesting that these indices may be particularly sensitive to semantic dysfunction associated with early AD.

Regional white matter hyperintensities: aging, Alzheimer's disease risk, and cognitive function.

White matter hyperintensities (WMH) of presumed vascular origin, as seen on T2-weighted fluid attenuated inversion recovery magnetic resonance imaging, are known to increase with age and are elevated in Alzheimers disease (AD). The cognitive implications of these common markers are not well understood. Previous research has primarily focused on global measures of WMH burden and broad localizations that contain multiple white matter tracts. The aims of this study were to determine the pattern of WMH accumulation with age, risk for AD, and the relationship with cognitive function utilizing a voxel-wise analysis capable of identifying specific white matter regions. A total of 349 participants underwent T1-weighted and high-resolution T2-weighted fluid attenuated inversion recovery magnetic resonance imaging and neuropsychological testing. Increasing age and lower cognitive speed and flexibility (a component of executive function), were both significantly associated with regional WMH throughout the brain. When age was controlled, lower cognitive speed and flexibility was independently associated with WMH in the superior corona radiata. Apolipoprotein E ε4 and parental family history of AD were not associated with higher burden of WMH. The results contribute to a larger body of literature suggesting that white matter measures are linked with processing speed, and illustrate the utility of voxel-wise analysis in understanding the effect of lesion location on cognitive function.

Cerebral Blood Flow is Diminished in Asymptomatic Middle-Aged Adults with Maternal History of Alzheimer's Disease

Cerebral blood flow (CBF) provides an indication of the metabolic status of the cortex and may have utility in elucidating preclinical brain changes in persons at risk for Alzheimers disease (AD) and related diseases. In this study, we investigated CBF in 327 well-characterized adults including patients with AD (n = 28), patients with amnestic mild cognitive impairment (aMCI, n = 23), older cognitively normal (OCN, n = 24) adults, and asymptomatic middle-aged adults (n = 252) with and without a family history (FH) of AD. Compared with the asymptomatic cohort, AD patients displayed significant hypoperfusion in the precuneus, posterior cingulate, lateral parietal cortex, and the hippocampal region. Patients with aMCI exhibited a similar but less marked pattern of hypoperfusion. Perfusion deficits within the OCN adults were primarily localized to the inferior parietal lobules. Asymptomatic participants with a maternal FH of AD showed hypoperfusion in hippocampal and parietofrontal regions compared with those without a FH of AD or those with only a paternal FH of AD. These observations persisted when gray matter volume was included as a voxel-wise covariate. Our findings suggest that having a mother with AD might confer a particular risk for AD-related cerebral hypoperfusion in midlife. In addition, they provide further support for the potential utility of arterial spin labeling for the measurement of AD-related neurometabolic dysfunction, particularly in situations where [18F]fluorodeoxyglucose imaging is infeasible or clinically contraindicated.

Subjective memory complaints, cortical thinning, and cognitive dysfunction in middle-age adults at risk of AD

Subjective memory complaints (SMCs) represent an individuals perception of subtle changes in memory in the absence of objective impairment in memory. However, it is not fully known whether persons with SMCs harbor brain alterations related to Alzheimers disease (AD) or whether they indeed demonstrate poorer cognitive performance.

Family history of Alzheimer disease predicts hippocampal atrophy in healthy middle-aged adults

Objective: To evaluate the longitudinal influence of family history (FH) of Alzheimer disease (AD) and apolipoprotein E ϵ4 allele (APOE4) on brain atrophy and cognitive decline over 4 years among asymptomatic middle-aged individuals. Methods: Participants were cognitively healthy adults with (FH+) (n = 60) and without (FH−) (n = 48) a FH of AD (mean age at baseline 54 years) enrolled in the Wisconsin Registry for Alzheimers Prevention. They underwent APOE genotyping, cognitive testing, and an MRI scan at baseline and 4 years later. A covariate-adjusted voxel-based analysis interrogated gray matter (GM) modulated probability maps at the 4-year follow-up visit as a function of FH and APOE4. We also examined the influence of parent of origin on GM atrophy. Parallel analyses investigated the effects of FH and APOE4 on cognitive decline. Results: Neither FH nor APOE4 had an effect on regional GM or cognition at baseline. Longitudinally, a FH × APOE4 interaction was found in the right posterior hippocampus, which was driven by a significant difference between the FH+ and FH− subjects who were APOE4−. In addition, a significant FH main effect was observed in the left posterior hippocampus. No significant APOE4 main effects were detected. Persons with a maternal history of AD were just as likely as those with a paternal history of AD to experience posterior hippocampal atrophy. There was no longitudinal decline in cognition within the cohort. Conclusion: Over a 4-year interval, asymptomatic middle-aged adults with FH of AD exhibit significant atrophy in the posterior hippocampi in the absence of measurable cognitive changes. This result provides further evidence that detectable disease-related neuroanatomic changes do occur early in the AD pathologic cascade.

CHANGES IN ADOLESCENTS’ PERCEPTIONS OF THE AGED: THE EFFECTS OF INTERGENERATIONAL CONTACT

Changes in adolescents’ perceptions of people over 60 years old occurred following two months of daily intergenerational contact in a naturalistic setting (i.e., the school lunch period). Sixth‐, seventh‐, and eighth‐graders’ perceptions of the aged became less negative and less stereotyped. Boys had more negative stereotyped perceptions of the aged than girls, and the girls indicated greater willingness to interact with the elderly. Girls changed their perceptions of the aged more than boys, and younger adolescents changed their perceptions more than older adolescents. Most of the changes in perceptions occurred in response to two types of items: those focusing on physical characteristics and those dealing with aspects of insecurity. These results and suggestions for future research are discussed in relation to previous studies on educational experiences that shape adolescents’ attitudes and stereotyped perceptions toward aging and the aged.

Children of persons with Alzheimer disease: what does the future hold?

Children of persons with Alzheimer disease (AD), as a group, face an increased risk of developing AD. Many of them, throughout their adult lives, seek input on how to reduce their chances of one day suffering their parents fate. We examine the state of knowledge with respect to risk and protective factors for AD and recommend a research agenda with special emphasis on AD offspring.

Anxiety and problem solving in middle-aged and elderly adults

This study was designed to examine effects of differences in age, health, education, and sex on state and trait anxiety, and to assess interrelations between anxiety and performance on reasoning and problem solving tests. A significant main effect of health status was obtained for trait anxiety, but age, education, and sex effects were nonsignificant for both anxiety variables. Anxiety ratings were inversely correlated with performance on tests of reasoning and problem solving (traditional and practical Piagetian tasks, matrices, and similarities), but the pattern of intercorrelations was stronger within the middle-aged (40-59 years) as opposed to the elderly (60-79 years) groups. The findings fail to support the hypothesis that anxiety increases with age, or that the elderly are disproportionately affected by anxiety in testing situations.

Reflections of biological changes in the psychological performance of the aged

It is demonstrated in the course of a longitudinal study of aged twins that individuals who developed symptoms resulting in a psychiatric diagnosis of dementia had significantly lower scores on three tests of cognitive function as early as 20 years before the diagnosis was made. Prospective longitudinal studies will be required to confirm the utility of psychometric tests as predictors of subsequent dementia; nonetheless, the present results suggest that it may be possible to identify behavioral phenotypes of dementia-prone aged persons.