Margaret Crossley

Letter and category fluency in community-dwelling Canadian seniors: a comparison of normal participants to those with dementia of the Alzheimer or vascular type.

Measures of letter (FAS) and category (Animal Naming) fluency were completed by community-dwelling, cognitively normal seniors (n = 635), and by individuals diagnosed with dementia of the Alzheimer type (DAT) (n = 155), or with vascular dementia (n = 39). Among normal seniors, category, but not letter fluency, declined with age, females performed better than males on letter but not on category fluency, and performance increased with education on both tasks. Among participants with DAT, letter fluency was influenced by level of education, whereas category fluency was education-, age-, and gender-invariant. Both measures differentiated normal seniors from those with dementia. Category fluency was more impaired than letter fluency at both mild and moderate stages of dementia, but neither task differentiated DAT from vascular dementia.

Improving access to dementia care: Development and evaluation of a rural and remote memory clinic

The availability, accessibility and acceptability of services are critical factors in rural health service delivery. In Canada, the aging population and the consequent increase in prevalence of dementia challenge the ability of many rural communities to provide specialized dementia care. This paper describes the development, operation and evaluation of an interdisciplinary memory clinic designed to improve access to diagnosis and management of early stage dementia for older persons living in rural and remote areas in the Canadian province of Saskatchewan. We describe the clinic structure, processes and clinical assessment, as well as the evaluation research design and instruments. Finally, we report the demographic characteristics and geographic distribution of individuals referred during the first three years.

Age-related differences in concurrent-task performance of normal adults: evidence for a decline in processing resources.

A concurrent-task paradigm was used to investigate age-related differences in the attentional capacity of 92 right-handed adults. Young, middle-aged, and elderly Ss were compared as they performed speeded, unimanual finger tapping with and without concurrent silent reading, speaking, and maze completion. There were 2 levels of difficulty for each cognitive task. The decrement in tapping rate from the single- to dual-task condition increased linearly with age. Concurrent-task tapping was slowed more by difficult than by easy tasks, and difficult tasks had a disproportionately disruptive effect on the concurrent performance of elderly Ss. The heightened vulnerability of the elderly to concurrent-task effects cannot be attributed parsimoniously to either general slowing or diminution of a specific resource. Instead the results suggest a reduction in a general-purpose processing resource with increasing age.

The effect of age and sex on clustering and switching during speeded verbal fluency tasks

Past research has been inconsistent with regard to the effects of normal aging and sex on strategy use during verbal fluency performance. In the present study, both Troyer et al.s (1997) and Abwender et al.s (2001) scoring methods were used to measure switching and clustering strategies in 60 young and 72 older adults, equated on verbal ability. Young adults produced more words overall and switched more often during both phonemic and semantic fluency tasks, but performed similarly to older adults on measures of clustering. Although there were no sex differences in total words produced on either fluency task, males produced larger clusters on both tasks, and females switched more frequently than males on the semantic but not on the phonemic fluency task. Although clustering strategies appear to be relatively age-insensitive, age-related changes in switching strategies resulted in fewer overall words produced by older adults. This study provides evidence of age and sex differences in strategy use during verbal fluency tests, and illustrates the utility of combining Troyers and Abwenders scoring procedures with in-depth categorization of clustering to understand interactions between age and sex during semantic fluency tasks.

Neurocognitive Influences on Health Behavior in a Community Sample

CONTEXT Dominant models of individual health behavior omit biological variables entirely and are composed almost exclusively of social-cognitive and conative variables. Research from the neurosciences suggests a role for brain function in explaining behaviors that require active self-regulation for consistent performance. However, the association between brain function and health behavior is underexplored. OBJECTIVE To examine the predictive power of executive function for 2 health risk behaviors and 2 health protective behaviors in healthy adults. DESIGN A cross-sectional community sample (N = 216) of adults 20-100 years of age were administered a battery of neuropsychological tests and completed self-report questionnaires regarding their health practices. It was hypothesized that poor performance on neuropsychological tests tapping executive function would be associated with poor health behavior tendencies. RESULTS Errors on the Stroop task were positively associated with health risk behavior and negatively associated with health protective behavior after controlling for demographics, education, and IQ. CONCLUSION Executive function is associated with health behavior tendencies. If the association is causal, explanatory models of individual health behavior should be revised to account for individual differences in biologically imbued self-regulatory abilities.

Clustering and switching strategies during verbal fluency performance differentiate Alzheimer's disease and healthy aging.

Clustering and switching strategies during phonemic and semantic verbal fluency tasks as defined by Troyer et al. (1997), Abwender et al. (2001), and Lanting et al. (2009) were compared using archival data to determine which scoring procedures best differentiate healthy older adults (n = 26) from individuals with early-stage Alzheimers disease (AD, n = 26). Total word production showed the largest group difference, especially for semantic fluency. The AD group produced fewer switches when compared to the healthy control group, whereas the groups did not differ in cluster size. The AD group also accessed fewer novel semantic subcategories, presumably due to reduced access to semantic memory storage rather than lower processing speed. Clustering and switching scores on the phonemic task did not add information above total words produced, consistent with previous research indicating these variables are most informative in relation to semantic fluency.

Processing Speed, Attentional Capacity, and Age-Related Memory Change

This study compared the relative importance (i.e., proportion of shared variance) of attentional capacity and processing speed accounts of cognitive aging to predict age differences in episodic and working memory performance. Right-handed adults (n = 100), 18 to 88 years of age, completed measures of attentional capacity (divided attention), processing speed, and episodic and working memory. The results provide little support for the predictive utility of the attentional capacity construct, independent of processing speed ability in accounting for age-specific episodic memory relations. The results are, however, consistent with the notion that attentional capacity mediates aspects of age-related working memory change.

Endocrine therapy is associated with low performance on some estrogen-sensitive cognitive tasks in postmenopausal women with breast cancer.

This study investigated the effects of endocrine therapy (i.e., tamoxifen and anastrozole) on cognitive functioning by comparing 28 postmenopausal women with breast cancer to 37 healthy age-equivalent controls. Participants completed neuropsychological tests previously shown to be estrogen sensitive (e.g., verbal memory, letter fluency). A significant treatment effect was observed on speeded measures of letter fluency, complex visuomotor attention, and manual dexterity, but not on measures of verbal or object-location memory, or on tests presumed to be estrogen insensitive (e.g., spatial ability). In partial support of previous research, these results indicate that endocrine therapy can have detrimental effects on speeded higher brain functions but not necessarily on memory.

Evaluation of Telehealth for Preclinic Assessment and Follow-Up in an Interprofessional Rural and Remote Memory Clinic.

Using data from a sample of 169 patients, this study evaluates the acceptability and feasibility of telehealth videoconferencing for preclinic assessment and follow-up in an interprofessional memory clinic for rural and remote seniors. Patients and caregivers are seen via telehealth prior to the in-person clinic and followed up at 6 weeks, 12 weeks, 6 months, 1 year, and yearly. Patients are randomly assigned to in-person (standard care) or telehealth for the first follow-up, then alternating between the two modes of treatment, prior to 1-year follow-up. On average, telehealth appointments reduce participants’ travel by 426 km per round trip. Findings show that telehealth coordinators rated 85% of patients and 92% of caregivers as comfortable or very comfortable during telehealth. Satisfaction scales completed by patient–caregiver dyads show high satisfaction with telehealth. Follow-up questionnaires reveal similar satisfaction with telehealth and in-person appointments, but telehealth is rated as significantly more convenient. Predictors of discontinuing follow-up are greater distance to telehealth, old-age patient, lower telehealth satisfaction, and lower caregiver burden.

Development and evaluation of a telehealth videoconferenced support group for rural spouses of individuals diagnosed with atypical early-onset dementias

Atypical and early-onset dementias can be particularly problematic for family caregivers, and support groups aimed at memory loss and Alzheimer’s disease are not always helpful. Unfortunately, little has been developed specifically for caregivers of individuals with atypical dementias such as the frontotemporal dementias. Compounding the lack of access to interventions targeted specifically at caregivers of individuals with atypical and early-onset dementias are the unique needs of rural caregivers. Due to the relative infrequency of these particular dementias and the large geographical distances between rural caregivers, technology-facilitation is required for any group-based intervention. This paper describes the development of a secure telehealth videoconferenced support group for rural spouses of individuals with atypical and early-onset dementias. In addition, we provide preliminary evidence of effectiveness and describe a template for future groups based on the key therapeutic aspects of this novel technology-facilitated intervention.