Callosal Interhemispheric Communication in Mild Traumatic Brain Injury: A Mediation Analysis on WM Microstructure Effects.

BACKGROUND AND PURPOSE: Because the corpus callosum connects the left and right hemispheres and a variety of WM bundles across the brain in complex ways, damage to the neighboring WM microstructure may specifically disrupt interhemispheric communication through the corpus callosum following mild traumatic brain injury. Here we use a mediation framework to investigate how callosal interhemispheric communication is affected by WM microstructure in mild traumatic brain injury. MATERIALS AND METHODS: Multishell diffusion MR imaging was performed on 23 patients with mild traumatic brain injury within 1 month of injury and 17 healthy controls, deriving 11 diffusion metrics, including DTI, diffusional kurtosis imaging, and compartment-specific standard model parameters. Interhemispheric processing speed was assessed using the interhemispheric speed of processing task (IHSPT) by measuring the latency between word presentation to the 2 hemivisual fields and oral word articulation. Mediation analysis was performed to assess the indirect effect of neighboring WM microstructures on the relationship between the corpus callosum and IHSPT performance. In addition, we conducted a univariate correlation analysis to investigate the direct association between callosal microstructures and IHSPT performance as well as a multivariate regression analysis to jointly evaluate both callosal and neighboring WM microstructures in association with IHSPT scores for each group. RESULTS: Several significant mediators in the relationships between callosal microstructure and IHSPT performance were found in healthy controls. However, patients with mild traumatic brain injury appeared to lose such normal associations when microstructural changes occurred compared with healthy controls. CONCLUSIONS: This study investigates the effects of neighboring WM microstructure on callosal interhemispheric communication in healthy controls and patients with mild traumatic brain injury, highlighting that neighboring noncallosal WM microstructures are involved in callosal interhemispheric communication and information transfer. Further longitudinal studies may provide insight into the temporal dynamics of interhemispheric recovery following mild traumatic brain injury.

Veteran Beliefs About the Causes of Gulf War Illness and Expectations for Improvement.

BACKGROUND: Individuals' beliefs about the etiology of persistent physical symptoms (PPS) are linked to differences in coping style. However, it is unclear which attributions are related to greater expectations for improvement. METHOD AND RESULTS: A cross-sectional regression analysis (N = 262) indicated that Veterans with Gulf War Illness (GWI) who attributed their GWI to behavior, (e.g., diet and exercise), had greater expectations for improvement (p = .001) than those who attributed their GWI to deployment, physical, or psychological causes (p values > .05). CONCLUSIONS: Findings support the possible clinical utility of exploring perceived contributing factors of PPS, which may increase perceptions that improvement of PPS is possible. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02161133.

Comparison of Informational and Educational Resource Provision for Individuals Living With Traumatic Brain Injury Based on Language, Nativity, and Neighborhood.

OBJECTIVE: To examine a resource provision program for individuals living with moderate-to-severe traumatic brain injury (TBI), using a comparison of the resources provided across social differences of language, nativity, and neighborhood. SETTING: The Rusk Rehabilitation TBI Model System (RRTBIMS) collects data longitudinally on individuals from their associated private and public hospitals, located in New York City. PARTICIPANTS: A total of 143 individuals with TBI or their family members. DESIGN: An observational study of relative frequency of resource provision across variables of language, nativity, and neighborhood, using related-samples nonparametric analyses via Cochran's Q test. MAIN MEASURES: Variables examined were language, place of birth, residence classification as medically underserved area/population (MUA), and resource categories. RESULTS: Results indicate that US-born persons with TBI and those living in medically underserved communities are provided more resources than those who are born outside the United States or reside in communities identified as adequately medically served. Language was not found to be a factor. CONCLUSION: Lessons learned from this research support the development of this resource provision program, as well as guide future programs addressing the gaps in health information resources for groups negatively impacted by social determinants of health (SDoH). An approach with immigrant participants should take steps to elicit questions and requests, or offer resources explicitly. We recommend research looking at what interpreter strategies are most effective and research on SDoH in relation to the dynamic interaction of variables in the neighborhood setting.

Effect of Problem-solving Treatment on Self-reported Disability Among Veterans With Gulf War Illness: A Randomized Clinical Trial.

Importance: Few evidence-based treatments are available for Gulf War illness (GWI). Behavioral treatments that target factors known to maintain the disability from GWI, such as problem-solving impairment, may be beneficial. Problem-solving treatment (PST) targets problem-solving impairment and is an evidence-based treatment for other conditions. Objective: To examine the efficacy of PST to reduce disability, problem-solving impairment, and physical symptoms in GWI. Design, Setting, and Participants: This multicenter randomized clinical trial conducted in the US Department of Veterans Affairs compared PST with health education in a volunteer sample of 511 Gulf War veterans with GWI and disability (January 1, 2015, to September 1, 2019); outcomes were assessed at 12 weeks and 6 months. Statistical analysis was conducted between January 1, 2019, and December 31, 2020. Interventions: Problem-solving treatment taught skills to improve problem-solving. Health education provided didactic health information. Both were delivered by telephone weekly for 12 weeks. Main Outcomes and Measures: The primary outcome was reduction from baseline to 12 weeks in self-report of disability (World Health Organization Disability Assessment Schedule). Secondary outcomes were reductions in self-report of problem-solving impairment and objective problem-solving. Exploratory outcomes were reductions in pain, pain disability, and fatigue. Results: A total of 268 veterans (mean [SD] age, 52.9 [7.3] years; 88.4% male; 66.8% White) were randomized to PST (n = 135) or health education (n = 133). Most participants completed all 12 sessions of PST (114 of 135 [84.4%]) and health education (120 of 133 [90.2%]). No difference was found between groups in reductions in disability at the end of treatment. Results suggested that PST reduced problem-solving impairment (moderate effect, 0.42; P = .01) and disability at 6 months (moderate effect, 0.39; P = .06) compared with health education. Conclusions and Relevance: In this randomized clinical trial of the efficacy of PST for GWI, no difference was found between groups in reduction in disability at 12 weeks. Problem-solving treatment had high adherence and reduced problem-solving impairment and potentially reduced disability at 6 months compared with health education. These findings should be confirmed in future studies. Trial Registration: ClinicalTrials.gov Identifier: NCT02161133.

Development of an MMPI reference group for outpatients with persisting symptoms following mild TBI.

OBJECTIVE: To develop an MMPI-2-RF reference group for persistently symptomatic patients with mTBI in order to aid interpretation and better evaluate atypical scale elevations. METHOD: Using the Q Local MMPI-2-RF Comparison Group Generator (CGG), 200 valid MMPI-2-RF profiles were aggregated for mTBI outpatients with persisting symptoms 2-24 months post injury. RESULTS: Compared to established MMPI general population norms, individuals with persisting symptoms demonstrated elevations on several scales, primarily in cognitive and somatic domains. T scores > 60 and standard deviations > 10 were observed for the F-r (Infrequent Responses), Fs (Infrequent Somatic Responses), FBS-r (Symptom Validity), RBS (Response Bias Scale), RC1 (Somatic Complaints), MLS (Malaise), HPC (Head Pain Complaints), NUC (Neurological Complaints), and COG (Cognitive Complaints) scales. All other scales were consistent with established norms for the general population. CONCLUSION: This study is the first to establish an empirically derived MMPI reference group for individuals with persisting symptoms following mTBI. By comparing MMPI profiles of patients with mTBI against this reference group, clinicians may be better able to identify abnormal symptomatology. Evaluating profiles within this context may allow for more accurate case conceptualization and targeted treatment recommendations for those patients who demonstrate disproportionate symptomatology outside the range of the mTBI reference group.

The effects of plasticity-based cognitive rehabilitation on resting-state functional connectivity in chronic traumatic brain injury: A pilot study.

BACKGROUND: Traumatic brain injury (TBI) often results in chronic impairments to cognitive function, and these may be related to disrupted functional connectivity (FC) of the brain at rest. OBJECTIVE: To investigate changes in default mode network (DMN) FC in adults with chronic TBI following 40 hours of auditory processing speed training. METHODS: Eleven adults with chronic TBI underwent 40-hours of auditory processing speed training over 13-weeks and seven adults with chronic TBI were assigned to a non-intervention control group. For all participants, resting-state FC and cognitive and self-reported function were measured at baseline and at a follow-up visit 13-weeks later. RESULTS: No significant group differences in cognitive function or resting-state FC were observed at baseline. Following training, the intervention group demonstrated objective and subjective improvements on cognitive measures with moderate-to-large effect sizes. Repeated measures ANCOVAs revealed significant (p < 0.001) group×time interactions, suggesting training-related changes in DMN FC, and semipartial correlations demonstrated that these were associated with changes in cognitive functioning. CONCLUSIONS: Changes in the FC between the DMN and other resting-state networks involved in the maintenance and manipulation of internal information, attention, and sensorimotor functioning may be facilitated through consistent participation in plasticity-based auditory processing speed training in adults with chronic TBI.

Cognitive Dependence in Physically Independent Patients at Discharge From Acute Traumatic Brain Injury Rehabilitation.

OBJECTIVE: To determine the incidence of cognitive dependence in adults who are physically independent at discharge from acute traumatic brain injury (TBI) rehabilitation. DESIGN: Analysis of historical clinical and demographic data obtained from inpatient stay. SETTING: Inpatient rehabilitation unit in a large, metropolitan university hospital. PARTICIPANTS: Adult inpatients with moderate to severe TBI (N=226) who were physically independent at discharge from acute rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: FIM Motor and Cognitive subscales, discharge destination, and care plan. RESULTS: Approximately 69% (n=155) of the physically independent inpatients were cognitively dependent at discharge from acute rehabilitation, with the highest proportions of dependence found in the domains of problem solving and memory. Most (82.6%; n=128) of these physically independent, yet cognitively dependent, patients were discharged home. Of those discharged home, 82% (n=105) were discharged to the care of family members, and 11% (n=15) were discharged home alone. Patients from racial and ethnic minority backgrounds were significantly more likely than White patients to be discharged while cognitively dependent. CONCLUSIONS: The majority of physically independent patients with TBI were cognitively dependent at the time of discharge from acute inpatient rehabilitation. Further research is needed to understand the effect of cognitive dependence on caregiver stress and strain and the disproportionate burden on racial and ethnic minority patients and families. Given the potential functional and safety limitations imposed by cognitive deficits, health care policy and practice should facilitate delivery of cognitive rehabilitation services in acute TBI rehabilitation.

Veterans with Gulf War Illness perceptions of management strategies.

AIMS: Gulf War Illness (GWI) is a prevalent and disabling condition characterized by persistent physical symptoms. Clinical practice guidelines recommend self-management to reduce the disability from GWI. This study evaluated which GWI self-management strategies patients currently utilize and view as most effective and ineffective. MATERIALS AND METHODS: Data were collected from 267 Veterans during the baseline assessment of a randomized clinical trial for GWI. Respondents answered 3 open-ended questions regarding which self-management strategies they use, view as effective, and view as ineffective. Response themes were coded, and code frequencies were analyzed. KEY FINDINGS: Response frequencies varied across questions (in-use: n = 578; effective: n = 470; ineffective: n = 297). Healthcare use was the most commonly used management strategy (38.6% of 578), followed by lifestyle changes (28.5% of 578), positive coping (13% of 578), and avoidance (13.7% of 578). When asked about effective strategies, healthcare use (25.9% of 470), lifestyle change (35.7% of 470), and positive coping (17.4% of 470) were identified. Avoidance was frequently identified as ineffective (20.2% of 297 codes), as was invalidating experiences (14.1% of 297) and negative coping (10.4% of 297). SIGNIFICANCE: Patients with GWI use a variety of self-management strategies, many of which are consistent with clinical practice guidelines for treating GWI, including lifestyle change and non-pharmacological strategies. This suggests opportunities for providers to encourage effective self-management approaches that patients want to use.

Coping with Medically Unexplained Physical Symptoms: the Role of Illness Beliefs and Behaviors.

BACKGROUND: Medically unexplained syndromes (MUS) are both prevalent and disabling. While illness beliefs and behaviors are thought to maintain MUS-related disability, little is known about which specific behavioral responses to MUS are related to disability or the way in which beliefs and behaviors interact to impact functioning. The purpose of the present study was to examine the relationship between illness beliefs and disability among patients with MUS, and assess the extent to which behaviors mediate this relationship. METHODS: The study examined data from the baseline assessment of a multi-site randomized controlled trial (RCT). Participants were 248 veterans with MUS. Illness beliefs, behavioral responses to illness, and disability were assessed through self-report questionnaire. Data were analyzed using mediation analysis. RESULTS: Threat-related beliefs predicted greater disability through decreased activity and increased practical support seeking. Protective beliefs predicted less disability through reductions in all-or-nothing behavior and limiting behavior. CONCLUSIONS: These outcomes suggest that all-or-nothing behavior, limiting behavior, and practical support seeking are important in the perpetuation of disability among those with MUS. This has implications for improving MUS treatment by highlighting potential treatment targets. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02161133.

Impact of racial-ethnic minority status and systemic vulnerabilities on time to acute TBI rehabilitation admission in an urban public hospital setting.

PURPOSE/OBJECTIVE: Racial/ethnic minorities and other vulnerable social groups experience health care disparities. There is a lack of research exploring how time to acute rehabilitation admission is impacted by race/ethnicity and other marginalizing systemic vulnerabilities. The purpose of this study is to investigate whether race/ethnicity and other sociodemographic vulnerabilities impact expediency of acute rehabilitation admission following traumatic brain injury (TBI). Research Method/Design: This study is a secondary analysis of an existing dataset of 111 patients admitted for acute TBI rehabilitation at an urban public hospital. Patient groups were defined by race/ethnicity (People of color or White) and vulnerable group status (high or low vulnerable group membership [VGM]). RESULTS: White patients are admitted to acute TBI rehabilitation significantly faster than people of color. After taking vulnerabilities into account, high VGM people of color experience the most severe injuries and take the longest to receive acute TBI rehabilitation. Despite small differences in injury severity, low VGM people of color take longer to be admitted to acute TBI rehabilitation than White patients. High VGM White patients have less severe injuries yet take longer to be admitted to acute rehabilitation than low VGM White patients. Finally, notable differences exist between White patients and patients of color on rater-based injury severity scales that are discordant with severity as measured by more objective markers. CONCLUSIONS/IMPLICATIONS: Overall, findings indicate that sociodemographic factors including race/ethnicity and systemic vulnerabilities impact injury severity and time to acute TBI rehabilitation admission. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Problem solving, biofeedback, and severe brain injury: The moderating role of positive affect.

OBJECTIVE: To examine how positive affect influences ability to benefit from heart rate variability (HRV) biofeedback treatment for individuals with severe brain injury. METHOD: 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

Working Memory And Brain Tissue Microstructure: White Matter Tract Integrity Based On Multi-Shell Diffusion MRI.

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.

Cluster Analysis of Vulnerable Groups in Acute Traumatic Brain Injury Rehabilitation.

OBJECTIVE: To analyze the complex relation between various social indicators that contribute to socioeconomic status and health care barriers. DESIGN: Cluster analysis of historical patient data obtained from inpatient visits. SETTING: Inpatient rehabilitation unit in a large urban university hospital. PARTICIPANTS: Adult patients (N=148) receiving acute inpatient care, predominantly for closed head injury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: We examined the membership of patients with traumatic brain injury in various "vulnerable group" clusters (eg, homeless, unemployed, racial/ethnic minority) and characterized the rehabilitation outcomes of patients (eg, duration of stay, changes in FIM scores between admission to inpatient stay and discharge). RESULTS: The cluster analysis revealed 4 major clusters (ie, clusters A-D) separated by vulnerable group memberships, with distinct durations of stay and FIM gains during their stay. Cluster B, the largest cluster and also consisting of mostly racial/ethnic minorities, had the shortest duration of hospital stay and one of the lowest FIM improvements among the 4 clusters despite higher FIM scores at admission. In cluster C, also consisting of mostly ethnic minorities with multiple socioeconomic status vulnerabilities, patients were characterized by low cognitive FIM scores at admission and the longest duration of stay, and they showed good improvement in FIM scores. CONCLUSIONS: Application of clustering techniques to inpatient data identified distinct clusters of patients who may experience differences in their rehabilitation outcome due to their membership in various "at-risk" groups. The results identified patients (ie, cluster B, with minority patients; and cluster D, with elderly patients) who attain below-average gains in brain injury rehabilitation. The results also suggested that systemic (eg, duration of stay) or clinical service improvements (eg, staff's language skills, ability to offer substance abuse therapy, provide appropriate referrals, liaise with intensive social work services, or plan subacute rehabilitation phase) could be beneficial for acute settings. Stronger recruitment, training, and retention initiatives for bilingual and multiethnic professionals may also be considered to optimize gains from acute inpatient rehabilitation after traumatic brain injury.

White Matter Tract Integrity: An Indicator of Axonal Pathology after Mild Traumatic Brain Injury.

We seek to elucidate the underlying pathophysiology of injury sustained after mild traumatic brain injury (mTBI) using multi-shell diffusion magnetic resonance imaging, deriving compartment-specific white matter tract integrity (WMTI) metrics. WMTI allows a more biophysical interpretation of white matter (WM) changes by describing microstructural characteristics in both intra- and extra-axonal environments. Thirty-two patients with mTBI within 30 days of injury and 21 age- and sex-matched controls were imaged on a 3 Tesla magnetic resonance scanner. Multi-shell diffusion acquisition was performed with five b-values (250-2500 sec/mm2) along 6-60 diffusion encoding directions. Tract-based spatial statistics (TBSS) was used with family-wise error (FWE) correction for multiple comparisons. TBSS results demonstrated focally lower intra-axonal diffusivity (Daxon) in mTBI patients in the splenium of the corpus callosum (sCC; p < 0.05, FWE-corrected). The area under the curve value for Daxon was 0.76 with a low sensitivity of 46.9% but 100% specificity. These results indicate that Daxon may be a useful imaging biomarker highly specific for mTBI-related WM injury. The observed decrease in Daxon suggests restriction of the diffusion along the axons occurring shortly after injury.

Screening Instruments for the Early Detection of Cognitive Impairment in Patients with Multiple Sclerosis.

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.

Anxiety as a primary predictor of functional impairment after acquired brain injury: a brief report.

OBJECTIVE: Cognitive and emotional symptoms are primary causes of long-term functional impairment after acquired brain injury (ABI). Although the occurrence of post-ABI emotional difficulties is well-documented, most investigators have focused on the impact of depression on functioning after ABI, with few examining the role of anxiety. Knowledge of the latter's impact is essential for optimal treatment planning in neurorehabilitation settings. The purpose of the present study is therefore to examine the predictive relationships between cognition, anxiety, and functional impairment in an ABI sample. METHOD: Multiple regression analyses were conducted with a sample of 54 outpatients with ABI. Predictors selected from an archival data set included standardized neuropsychological measures and Beck Anxiety Inventory scores. Dependent variables were caregiver ratings of functional impairments in the Affective/Behavioral, Cognitive, and Physical/Dependency domains. RESULTS: Anxiety predicted a significant proportion of the variance in caregiver-assessed real-life affective/behavioral and cognitive functioning. In contrast, objective neuropsychological test scores did not contribute to the variance in functional impairment. Neither anxiety nor neuropsychological test scores significantly predicted impairment in everyday physical/dependency function. CONCLUSION: These findings support the role of anxiety in influencing functional outcome post-ABI and suggest the necessity of addressing symptoms of anxiety as an essential component of treatment in outpatient neurorehabilitation.

Heart rate variability biofeedback, executive functioning and chronic brain injury.

PRIMARY OBJECTIVE: To determine if individuals with brain injury can modify heart rate variability (HRV) through biofeedback and, if so, enhance its pattern to improve emotional regulation and problem-solving ability. DESIGN: A quasi-experimental design with repeated measures was employed. Thirteen individuals aged 23-63 years with severe brain injury (13-40 years post-onset) participating in a community-based programme were enrolled. MAIN OUTCOMES: Response-to-treatment was measured with HRV indices, Behavior Rating Inventory of Executive Function (BRIEF-A-Informant) and attention/problem-solving tests. RESULTS: At post-treatment, HRV indices (Low Frequency/High Frequency [LF/HF] and coherence ratio) increased significantly. Increased LF/HF values during the second-half of a 10-minute session were associated with higher attention scores. Participants who scored better (by scoring lower) in informant ratings at pre-treatment had highest HRV scores at post-treatment. Accordingly, at post-treatment, families' ratings of participants' emotional control correlated with HRV indices; staffs' ratings of participants' working memory correlated with participants' HRV indices. Self-ratings of the BRIEF-A Task Monitoring scale at post-treatment correlated with family ratings at pre-treatment and post-treatment. CONCLUSIONS: Results demonstrate an association between regulation of emotions/cognition and HRV training. Individuals with severe, chronic brain injury can modify HRV through biofeedback. Future research should evaluate the efficacy of this approach for modifying behavioural problems.

Clinical applications of problem-solving research in neuropsychological rehabilitation: addressing the subjective experience of cognitive deficits in outpatients with acquired brain injury.

OBJECTIVE: The goal of this paper is to illustrate how the lessons learned in over 20 years of randomized clinical trials have advanced cognitive rehabilitation beyond traditional approaches to problem solving by more explicitly integrating subjective self-appraisal factors in routine clinical practice. RESULTS: The concept of problem orientation, as proposed by cognitive-behavioral psychologists, provides a much-needed framework for conceptualizing interventions to address the impact of subjective experience on cognitive functioning, within the context of cognitive remediation. By explicitly focusing on the beliefs, assumptions, and expectations that individuals with acquired brain injury have about their own cognitive functioning, the concept of problem orientation allows rehabilitation psychologists to add an element to interventions, not systematically addressed in standard approaches to cognitive remediation. Targeting objective deficits in cognitive remediation is necessary, but not sufficient: For optimal benefit, remedial interventions must address objective cognitive deficits and the patient's subjective experience of such deficits in tandem. CONCLUSION: Contemporary evidence-based treatment recommendations now typically include incorporating interventions to address motivational, attitudinal, and affective factors in cognitive remediation. Further research is needed to directly compare the effectiveness of cognitive rehabilitative interventions that systematically address subjective factors with those that do not.

The construct of problem solving in higher level neuropsychological assessment and rehabilitation.

Three inter-related studies examine the construct of problem solving as it relates to the assessment of deficits in higher level outpatients with traumatic brain injury (TBI). Sixty-one persons with TBI and 58 uninjured participants completed measures of problem solving and conceptually related constructs, which included neuropsychological tests, self-report inventories, and roleplayed scenarios. In Study I, TBI and control groups performed with no significant differences on measures of memory, reasoning, and executive function, but medium to large between-group differences were found on timed attention tasks. The largest between-group differences were found on psychosocial and problem-solving self-report inventories. In Study II, significant-other (SO) ratings of patient functioning were consistent with patient self-report, and for both self-report and SO ratings of patient problem solving, there was a theoretically meaningful pattern of correlations with timed attention tasks. In Study III, a combination of self-report inventories that accurately distinguished between participants with and without TBI, even when cognitive tests scores were in the normal range, was determined. The findings reflect intrinsic differences in measurement approaches to the construct of problem solving and suggest the importance of using a multidimensional approach to assessment.