Psychology, Department of

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“Do It-Yourself”: Home Blood Pressure as a Predictor of Traditional and Everyday Cognition in Older Adults

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2017-05-17
Abstract: 

Background

Hypertension guidelines recommend home blood pressure (HBP) monitoring in adjunct to office blood pressure (OBP) for its greater reproducibility and prognostic utility in the prevention of cardiovascular outcomes, especially stroke. To date, the relationship between HBP and cognitive function remains unexplored.

Methods

We examined HBP as a cognitive predictor in a multi-ethnic group of community-dwelling adults aged 60 and over (N = 133) using neuropsychological measures and analyzed the data using multiple regression analyses. We also employed “everyday cognition” measures that have been found to have higher prognostic utility for real-world functioning than traditional cognitive tasks.

Results

Good to perfect HBP monitoring compliance over seven days was achieved by 88.7% of the participants with superior reliability (ICC≥.96) to office readings. Higher home systolic BP and pulse pressure predicted worse processing speed, executive function, and everyday cognitive function, whereas lower home diastolic BP predicted worse everyday cognition. Office readings were similarly associated with everyday cognitive function but with no other cognitive measures.

Conclusion

Our findings are the first to validate HBP as a predictor of neuropsychological function in older adults beyond cognitive screening. Differential relationships among blood pressure variables and specific cognitive domains were observed. With proper standardization and training, we demonstrated that HBP can be obtained in a multi-ethnic community-dwelling older adult cohort. Our findings emphasize the importance of employing blood pressure and cognitive measures that are adequately sensitive to detect vascular-related cognitive impairment in a relatively healthy population. Implications regarding proper HBP measurement for hypertension management, cognitive health, and everyday function are discussed.

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Spatiotemporal Dynamics of Reward and Punishment Effects Induced By Associative Learning

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2018-11-26
Abstract: 

While reward associative learning has been studied extensively across different species, punishment avoidance learning has received far less attention. Of particular interest is how the two types of learning change perceptual processing of the learned stimuli. We designed a task that required participants to learn the association of emotionally neutral images with reward, punishment, and no incentive value outcomes through trial-and-error. During learning, participants received monetary reward, neutral outcomes or avoided punishment by correctly identifying corresponding images. Results showed an early bias in favor of learning reward associations, in the form of higher accuracy and fewer trials needed to reach learning criterion. We subsequently assessed electrophysiological learning effects with a task in which participants viewed the stimuli with no feedback or reinforcement. Critically, we found modulation of two early event-related potential components for reward images: the frontocentral P2 (170–230 ms) and the anterior N2/Early Anterior Positivity (N2/EAP; 210–310 ms). We suggest that reward associations may change stimuli detection and incentive salience as indexed by P2 and N2/EAP. We also reported, on an exploratory basis, a late negativity with frontopolar distribution enhanced by punishment images.

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Impact of Once- Versus Twice-Daily Tacrolimus Dosing on Medication Adherence in Stable Renal Transplant Recipients: A Canadian Single-Center Randomized Controlled Trial

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-08-17
Abstract: 

Background: Prevalence of immunosuppressant nonadherence in renal transplant recipients is high despite negative clinical outcomes associated with nonadherence. Simplification of dosing has been demonstrated to improve adherence in renal transplant recipients as measured through electronic monitoring and self-report.

Objective: The purpose of this study was to replicate and extend previous findings by measuring adherence with multiple methods in a Canadian sample.

Design: The study design was a randomized controlled medication dosing trial in adult renal transplant patients. The trial length was 4 months.

Setting: This study was conducted within the Solid Organ Transplant (SOT) Clinic at Vancouver General Hospital (VGH; Vancouver, Canada).

Patients: A total of 46 adult renal recipients (at least 1 year post-transplant) were recruited through the SOT clinic. With 8 withdrawals, 38 individuals completed all phases of the study.

Measurements: Medication adherence was measured for a period of 4 months using multiple methods, including electronic monitoring (MEMS [Medication Event Monitoring System]), pharmacy refill data (medication possession ratio [MPR]), and by self-report using the Adherence subscale of the Transplant Effects Questionnaire (TEQ).

Methods: Participants were randomized to twice-daily (n = 19) or once-daily tacrolimus dosing (n = 19) and followed over a 4-month period via monthly clinic study visits. Comparisons between the treatment groups were performed using the Mann-Whitney U and chi-square tests, for continuous and categorical variables, respectively.

Results: As outlined in Table 3, the once-daily dosing group showed significantly better MEMS Dose Adherence (P = .001), whereas MEMS Timing Adherence showed a tendency toward better adherence for this group, but was not significant (P = .052). MEMS Days Adherent (P = .418), MPR% (P = .123), and self-reported adherence (P = .284) did not differ between the once- and twice-daily dosing groups when measured as continuous variables. The MPR% was significantly better for the once-daily dosing group when measured dichotomously but not continuously (P = .044). Notably, most of those exposed to once-daily dosing (63.2%) preferred this to the twice-daily regimen.

Limitations: Limitations included small sample size and short follow-up period, precluding the examination of clinical outcome differences.

Conclusions: Results for dose adherence replicate the finding that dose simplification increases adherence to immunosuppressants as measured through electronic monitoring. Such an advantage for the once-daily dosing group was not seen across the 2 other electronic monitoring measurement variables (days and timing adherence). This study extends previous research by examining adherence in once versus twice-daily dosing via prescription refill data in a Canadian sample. Given the gravity of potential health outcomes associated with nonadherence, although results indicate inconsistencies in significance testing across measurement methods, the medium to large effect sizes seen in the data favoring better adherence with once-daily dosing provide an indication of the potential clinical significance of these findings.

Trial registration: This study was registered with ClinicalTrials.gov (NCT01334333) on April 11, 2011.

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Cognitive Impairment in Marginally Housed Youth: Prevalence and Risk Factors

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-10-08
Abstract: 

Objective: Homeless and marginally housed youth are particularly vulnerable members of society, and are known to experience numerous health problems, including psychiatric illness, substance use, and viral infection. Despite the presence of these risk factors for cognitive compromise, there is limited research on the cognitive functioning of homeless and marginally housed youth. The present study examines the degree and pattern of cognitive impairment and associations with key risk factors in a sample of marginally housed young adults.

Method: Participants (N = 101) aged 20–29 years old were recruited from single-room occupancy hotels, and underwent cognitive, psychiatric, neurological, and serological assessments.

Results: Forty percent of participants were identified as mildly cognitively impaired across multiple domains, and 16% were moderately-severely impaired. Deficits in memory and attention were most prevalent, while impairments in inhibitory control/processing speed and cognitive flexibility were also present but tended to be less severe. Developmental and historical factors (premorbid intellectual functioning, neurological soft signs, earlier exposure to and longer duration of homelessness or marginal housing), as well as current health risks (stimulant dependence and hepatitis C exposure), were associated with cognitive impairment.

Conclusions: The strikingly high rate of cognitive impairment in marginally housed young adults represents a major public health concern and is likely to pose a significant barrier to treatment and rehabilitation. These results suggest that the pathway to cognitive impairment involves both developmental vulnerability and modifiable risk factors. This study highlights the need for early interventions that address cognitive impairment and risk factors in marginalized young people.

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Classic Motor Chunking Theory Fails To Account for Behavioural Diversity and Speed in a Complex Naturalistic Task

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-06-13
Abstract: 

In tasks that demand rapid performance, actions must be executed as efficiently as possible. Theories of expert motor performance such as the motor chunking framework suggest that efficiency is supported by automatization, where many serial actions are automatized into smaller chunks, or groups of commonly co-occuring actions. We use the fast-paced, professional eSport StarCraft 2 as a test case of the explanatory power of the motor chunking framework and assess the importance of chunks in explaining expert performance. To do so, we test three predictions motivated by a simple motor chunking framework. (1) StarCraft 2 players should exhibit an increasing number of chunks with expertise. (2) The proportion of actions falling within a chunk should increase with skill. (3) Chunks should be faster than non-chunks containing the same atomic behaviours. Although our findings support the existence of chunks, they also highlight two problems for existing accounts of rapid motor execution and expert performance. First, while better players do use more chunks, the proportion of actions within a chunks is stable across expertise and expert sequences are generally more varied (the diversity problem). Secondly, chunks, which are supposed to enjoy the most extreme automatization, appear to save little or no time overall (the time savings problem). Instead, the most parsimonious description of our latency analysis is that players become faster overall regardless of chunking.

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(Re)Introducing Vygotsky’s Thought: From Historical Overview to Contemporary Psychology

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-08-07
Abstract: 

Theories formulated by Russian psychologist and educator Lev Vygotsky currently range from being applied and celebrated across multiple contexts to be considered outdated. In this paper, we maintain that such inconsistency in application stems from the overreliance on translated or reformulated Vygotskian theories, the attempts to understand these ideas in isolation from the scientific historical context of their development, and the impact of Vygotsky’s personal life circumstances on the development of his scholarship. It is known that Vygotsky’s untimely death prevented him from elaborating on his theoretical views and expanding his early empirical work. We suggest that Vygotsky’s scholarship could be better understood in light of the core principles that transcend all aspects of his work. In this paper, we elaborate on two such core principles: theories of language development and their relation to the integrated systemic approach to psychological development. We argue that although linguistic and historical boundaries have shaped the common perception of Vygotskian theories in anglophone research in a specific way, there is a potential for a renewed application of these theories to modern psychology that might be especially relevant in light of the increasingly interdisciplinary character of the modern science. To support our argument, we provide a brief overview and examples of potential connections between Vygotsky’s scholarship with contemporary landscape in psychological science. The paper presents a brief introduction to the topic of Vygotskian work and its application to modern psychology, rather than an addition to the field of Vygotskian scholarship. It is geared toward non-Vygotskian scholars and invites researchers working in interdisciplinary areas of psychology.

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The Support for Economic Inequality Scale: Development and Adjudication

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-06-21
Abstract: 

Past research has documented myriad pernicious psychological effects of high economic inequality, prompting interest into how people perceive, evaluate, and react to inequality. Here we propose, refine, and validate the Support for Economic Inequality Scale (SEIS)–a novel measure of attitudes towards economic inequality. In Study 1, we distill eighteen items down to five, providing evidence for unidimensionality and reliability. In Study 2, we replicate the scale’s unidimensionality and reliability and demonstrate its validity. In Study 3, we evaluate a United States version of the SEIS. Finally, in Studies 4–5, we demonstrate the SEIS’s convergent and predictive validity, as well as evidence for the SEIS being distinct from other conceptually similar measures. The SEIS is a valid and reliable instrument for assessing perceptions of and reactions to economic inequality and provides a useful tool for researchers investigating the psychological underpinnings of economic inequality.

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Article
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Diffusion Tensor Imaging of Neurocognitive Profiles in a Community Cohort Living in Marginal Housing

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-02-06
Abstract: 

Objective:  We investigated white matter differences associated with distinct neurocognitive profiles derived from a large cohort of marginally housed persons with comorbid physical and mental illnesses. Our prior work identified three profile cluster groups: a high functioning group (Cluster 1), a low functioning group with relative strength in decision‐making (Cluster 3), and an intermediary group with a relative decision‐making weakness (Cluster 2). This study extends previous findings of cortical gray matter differences between these groups with evidence for putative neurodevelopmental abnormalities in the low cognitive functioning group (i.e., Cluster 3). We hypothesized that altered white matter diffusion would be associated with the lowest functioning neurocognitive profile and would be associated with previously observed gray matter differences.

Method:  Participants from a socially impoverished neighborhood in Vancouver, Canada underwent neurocognitive evaluation and neuroimaging. We performed Tract‐Based Spatial Statistics using diffusion tensor imaging data from 184 participants to examine whole‐brain differences in white matter microstructure between cluster analytically derived neurocognitive profiles, as well as unitary neurocognitive measures. Correlations between frontal gray and white matter were also examined.

Results:  Cluster 3 showed increased diffusion in predominately bilateral frontal and interhemisphere tracts (vs. Clusters 1 and 2), with relatively greater diffusion in the left hemisphere (vs. Cluster 1). Differences in radial diffusivity were more prominent compared with axial diffusivity. A weak association between regional frontal fractional anisotropy and previously defined abnormalities in gyrification was observed.

Conclusions:  In a socially marginalized sample, we established several patterns in the covariation of white matter diffusion and neurocognitive functioning. These patterns elucidate the neurobiological substrates and vulnerabilities that are apt to underlie functional impairments inherent to this complex and heterogeneous population.

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A Psychometric Study of the Family Resilience Assessment Scale among Families of Children with Autism Spectrum Disorder

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-03-12
Abstract: 

Background: The family system represents a critical context within which children develop. Although raising a child with a disability may represent a challenge to this dynamic system, research demonstrates that families have the capacity to demonstrate both maladaptation and resilience in the face of related stressors. In the current study, we examined the psychometric properties of the Family Resilience Assessment Scale (FRAS) among families of children with autism spectrum disorder (ASD). This tool is the only measure of family resilience that seeks to identify within-family protective factors, including the extent to which they rely on adaptive belief systems, organizational patterns, and communication processes. Identifying protective processes utilized by those who show resilience is critical within both clinical practice and research, as it aligns with a strength-based perspective that builds on what families are doing well.

Methods: Participants included 174 caregivers of individuals with ASD (84% mothers). Caregivers completed the FRAS, as well as the Beach Center Family Quality of Life Scale. The 54-item FRAS was submitted to an exploratory factor analysis, using the iterated principal factor method with a promax rotation.

Results: Fifty-one items across 3 factors (Family Communication and Problem Solving, Utilizing Social and Economic Resources, Family Spirituality) were retained, explaining 52% of the total variance. The final scale demonstrated convergent validity with the Family Quality of Life assessment tool.

Conclusions: It is our hope that identifying the optimal scale structure will encourage other researchers to utilize this measure with families of children with ASD, thus continuing to advance the study of family resilience within this unique context.

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Research 101: A Process for Developing Local Guidelines for Ethical Research in Heavily Researched Communities

Peer reviewed: 
Yes, item is peer reviewed.
Date created: 
2019-07-01
Abstract: 

Background: Marginalized communities often attract more than their share of research. Too often, this research benefits researchers disproportionately and leaves such communities feeling exploited, misrepresented, and exhausted. The Downtown Eastside (DTES) neighborhood of Vancouver, Canada, has been the site of multiple public health epidemics related to injection drug use as well as the site of much community-led resistance and struggle that has led to the development of cutting-edge harm reduction interventions (e.g., North America’s first supervised injection facility, Insite) and a strong sense of community organization. This background has made the DTES one of the most heavily researched communities in the world. Amidst ongoing experiences of unethical or disrespectful research engagement in the neighborhood, a collaboration between local academic researchers and community representatives developed to explore how we could work together to encourage more respectful, community-responsive research and discourage exploitative or disrespectful research.

Methods: We developed a series of six weekly workshops called “Research 101.” These workshops brought together approximately 13 representatives from peer-based organizations in the DTES with a variety of experiences with research. Research 101 created space for community members themselves to discuss the pitfalls and potential of research in their neighborhood and to express community expectations for more ethical and respectful research.

Results: We summarized workshop discussions in a co-authored “Manifesto for Ethical Research in the Downtown Eastside.” This document serves as a resource to empower community organizations to develop more equitable partnerships with researchers and help researchers ground their work in the principles of locally developed “community ethics.” Manifesto guidelines include increased researcher transparency, community-based ethical review of projects, empowering peer researchers in meaningful roles within a research project, and taking seriously the need for reciprocity in the research exchange.

Conclusions: Research 101 was a process for eliciting and presenting a local vision of “community ethics” in a heavily researched neighborhood to guide researchers and empower community organizations. Our ongoing work involves building consensus for these guidelines within the community and communicating these expectations to researchers and ethics offices at local universities. We also describe how our Research 101 process could be replicated in other heavily researched communities.

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