Faculty Bibliography

Working memory is a complex cognitive process at the intersection of sensory processing, learning, and short-term memory and also has a general executive attention component. Impaired working memory is associated with a range of neurological and psychiatric disorders, but very little is known about how working memory relates to underlying white matter (WM) microstructure. In this study, we investigate the association between WM microstructure and performance on working memory tasks in healthy adults (right-handed, native English speakers). We combine compartment specific WM tract integrity (WMTI) metrics derived from multi-shell diffusion MRI as well as diffusion tensor/kurtosis imaging (DTI/DKI) metrics with Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) subtests tapping auditory working memory. WMTI is a novel tool that helps us describe the microstructural characteristics in both the intra- and extra-axonal environments of WM such as axonal water fraction (AWF), intra-axonal diffusivity, extra-axonal axial and radial diffusivities, allowing a more biophysical interpretation of WM changes. We demonstrate significant positive correlations between AWF and letter-number sequencing (LNS), suggesting that higher AWF with better performance on complex, more demanding auditory working memory tasks goes along with greater axonal volume and greater myelination in specific regions, causing efficient and faster information process.

OBJECTIVE:To examine how positive affect influences ability to benefit from heart rate variability (HRV) biofeedback treatment for individuals with severe brain injury. METHOD/METHODS:Secondary data analysis of a nonrandomized experimental study that assessed the efficacy of biofeedback treatment for executive dysfunction in 13 individuals with chronic severe brain injury. RESULTS:Bivariate correlations between the predictors (levels of HRV and positive affect) and the outcome (change in Category Test errors) showed large effect sizes for higher levels of HRV coherence (r = -.495, p = .085) but not for positive affect (r = .069, p = .824). Although positive affect had a negligible effect on Category Test improvements by itself, positive affect played a moderating role that complemented the effect of HRV coherence. HRV coherence had a stronger effect on Category Test performance among those participants who demonstrated higher positive affect. A regression model was fit that included main effects for HRV coherence and positive affect, as well as their interaction. The interaction term was significant in a 1-tailed test (b = -3.902, SE = 1.914, p = .072). CONCLUSIONS:Participants who had the most positive emotions made the most gains in the HRV biofeedback training and performed better posttreatment on a test designed to measure problem-solving ability. Results indicate that positive affect can improve cognition, specifically mental flexibility and abstract thinking. Addressing factors that shape negative affect such as irrational beliefs and self-doubt is an important target for therapeutic intervention even in those with severe, chronic deficits. (PsycINFO Database Record

BACKGROUND:While the cognitive sequelae of traumatic brain injury (TBI) are well known, emotional impairments after TBI are suboptimally characterized. Lack of awareness of emotional difficulties can make self-report unreliable. However, individuals with TBI demonstrate involuntary changes in heart rate variability which may enable objective quantification of emotional dysfunction. METHODS:Sixteen subjects with chronic TBI and 10 age-matched controls were tested on an emotional function battery during which they watched a series of film clips normed to elicit specific positively and negatively valenced emotions: amusement, sexual amusement, sadness, fear and disgust. Subjective responses to the emotional stimuli were also obtained. Additionally, surface electrodes measured cardiac and respiratory signals to compute heart rate variability (HRV), from which measures of parasympathetic activity, the respiratory frequency area (RFA) and sympathetic activity, the low frequency area (LFA), of the HRV frequency spectrum were derived. The Neurobehavioral Rating Scale-Revised (NRS-R) and the King-Devick (KD) test were administered to assess neurobehavioral dysfunction. RESULTS:The two groups showed no differences in subjective ratings of emotional intensity. Subjects with TBI showed significantly decreased sympathetic activity when viewing amusing stimuli and significantly increased sympathetic activity when viewing sad stimuli compared to controls. Most of the subjects did not show agitation, anxiety, depression, blunted affect, emotional withdrawal, decreased motivation or mental fatiguability on the NRS-R. However, 13/16 subjects with TBI demonstrated attention difficulty on the NRS-R which was positively correlated with the increased sympathetic activity during sad stimuli. Both attention difficulty and abnormal autonomic responses to sad stimuli were correlated with the timing on the KD test, which reflected difficulty with visual attention shifting. CONCLUSIONS:The HRV spectrum may be useful to identify subclinical emotional dysfunction in individuals with TBI. Attention difficulites, specifically impairment in visual attention shifting, may contribute to abnormal reactivity to sad stimuli that may be detected and potentially treated to improve emotional function.

The objective of this study was to investigate the efficacy of a group treatment protocol called NICE (Noticing you have a problem, Identifying the information you need for help, Compensatory strategies, Evaluating progress) to train help-seeking when wayfinding for individuals with acquired brain injury (ABI). Seven participants completed the NICE group treatment in an outpatient rehabilitation department at a university medical centre. A single subject multiple baseline design was employed to evaluate the efficacy of the NICE group treatment. The Social Behaviour Rating Scale and the Executive Function Route-Finding Task- Revised were repeated measures used to evaluate potential changes in help-seeking and wayfinding. Secondary outcome measures included pre- and post-treatment evaluation of social problem solving and social cognition. Results revealed that all participants improved on measures of help-seeking and wayfinding. Patterns of improvement and implications for rehabilitation are discussed. This is the first experimental study to evaluate the treatment of help-seeking behaviours and discuss its application to wayfinding in adults with ABI. Preliminary evidence supports further investigation of the NICE group treatment protocol.

Social workers play an essential role in facilitating veterans' reintegration into their communities and daily lives. Many veterans, particularly those who have been deployed, experience comorbid physical, psychological, and neurocognitive problems that significantly impact their health function in multiple domains. Veterans deployed to Operation Desert Shield/Operation Desert Storm have reported a wide range of persistent, diverse, medically unexplained symptoms that have come to be known as Gulf War Illness (GWI). These symptoms make it difficult for veterans to participate in daily activities, thereby impacting health function. There are few effective treatments to improve the health function for those with GWI. The goals of this article are to provide social workers with information about GWI, and describe how we modified an evidence-based treatment, problem-solving therapy, for veterans with GWI. This tailoring of an existing treatment may serve as a model for adapting evidence-based treatments for veterans and civilians with multiple chronic symptoms and other complex health concerns. Furthermore, the detailed description provided may facilitate dissemination of problem-solving therapy among social workers and trainees.

BACKGROUND: Cognitive impairments are common in individuals with MS and adversely affect functioning. Early detection of cognitive impairment, therefore, would enable earlier, and possibly more effective, treatment. We sought to compare self-reports with a short neuropsychological test as possible screening tools for cognitive impairment. METHODS: One hundred patients with MS were tested with the Minimal Assessment of Cognitive Function in Multiple Sclerosis; z scores were used to derive the Cognitive Index (CI). Receiver operator characteristic curve analyses were performed, with criteria for impairment set at -1.5 and -2.0 SD below the mean. Scores from two self-reports (the Multiple Sclerosis Neuropsychological Screening Questionnaire-Patient Version and the Behavior Rating Inventory of Executive Function-Adult Version [BRIEF-A]) and a neuropsychological test (the Symbol Digit Modalities Test [SDMT]) were entered as test variables. Exploratory regression analyses were conducted with 1) CI and self-reports and 2) CI and the Problem-Solving Inventory (PSI). RESULTS: Classification accuracy was high or moderately high for SDMT when the criterion was -2.0 or -1.5 SD, respectively, but low for the self-reports. Hierarchical linear regression showed that the SDMT alone was the best predictor of cognitive impairment; adding the self-reports did not improve the model. Exploratory analyses indicated that certain self-reports (BRIEF-A, PSI) provided some explanatory power in separate models. CONCLUSIONS: The SDMT is a more accurate screening tool for cognitive impairment; however, self-reports provide additional information and may complement objective testing. Results suggest that screening for cognitive impairment may require a multidimensional approach.