Traumatic brain injury: relation to executive dysfunction and the frontal lobes

Efficacy and safety of compound porcine cerebroside and ganglioside injection (CPCGI) versus piracetam on cognition and functional outcomes for adults with traumatic brain injury: A study protocol for randomized controlled trial

Background

Traumatic brain injury (TBI) is a common neurosurgical disease in emergency rooms with poor prognosis, imposing severe burdens on patients and their families. Evidence indicates that piracetam and compound porcine cerebroside and ganglioside injection (CPCGI) can improve cognitive levels in TBI patients to enhance functional prognosis, but there is still a research gap regarding the efficacy of CPCGI. This study aims to determine the effectiveness and safety of CPCGI in improving cognitive and functional outcomes in TBI patients.

Methods

This study is a multicenter, randomized, parallel-group, double-blind trial aiming to recruit 900 adult patients with mild to moderate TBI. After providing informed consent, 600 patients will be randomly assigned to the CPCGI group (20 ml/d, for 14 days), and 300 patients will be randomized to the piracetam group as a control (20 ml/d, for 14 days), followed up for 3 months after treatment. The primary outcome is the change in the Montreal Cognitive Assessment (MoCA) score from baseline after 3 months. The main secondary outcome measures include Mini-Mental State Examination (MMSE) scores, Glasgow Outcome Scale-Extended (GOS-E), and the Barthel Index at 1 and 3 months.

Discussion

This multi-center clinical trial aims to provide high-quality evidence on the efficacy and safety of CPCGI in improving cognitive and functional outcomes in mild to moderate TBI patients.

Trial registration

ChiCTR2000040466, date of registration: November 28, 2020.

Speed of processing training to improve cognition in moderate to severe TBI: a randomized clinical trial

Background

Moderate to severe traumatic brain injury (TBI) often results in cognitive deficits. Processing speed (PS) deficits are common, exerting a significant impact on daily life. Few studies have examined the efficacy of cognitive rehabilitation specifically for PS deficits in moderate to severe TBI.

Objective

Examine the efficacy of Speed of Processing Training (SOPT) in moderate to severe TBI. This protocol is a 10-session behavioral intervention for PS deficits that has been successfully used with other cognitively impaired populations.

Methods

This double-blind, placebo-controlled, randomized clinical trial included 46 participants with moderate to severe TBI, 22 randomly assigned to the treatment group and 24 to the placebo-control group. Baseline and follow-up measures included a task similar to the training task (UFOV), measures of near transfer (neuropsychological measures of processing speed: Symbol Digit Modalities Test (SDMT), Wechsler Adult Intelligence Scale-IV (WAIS-IV) Symbol Search, WAIS-IV Coding) and measures of far transfer [neuropsychological measures of learning and memory: the California Verbal Learning Test-II (CVLT-II), Memory Assessment Scales - Prose Memory (MAS-PM)].

Results

Significant improvement from pre-to post-SOPT was observed on all subtests of the UFOV, which is similar to the training task. There was no significant difference on neuropsychological measures of PS or new learning and memory post-treatment. Neuropsychological assessment 6-months post-treatment showed no significant change in PS ability over time. Monthly booster sessions did not impact performance at the 6-month follow-up.

Conclusion

Consistent with the SOPT literature, SOPT improves PS ability as measured by the UFOV, a task similar to the training task, in moderate to severe TBI. However, neither near nor far transfer was noted. That is, no improvement was noted on neuropsychological measures of PS.

A strike to the head: Parallels between the pediatric and adult human and the rodent in traumatic brain injury

Traumatic brain injury (TBI) is a condition that occurs commonly in children from infancy through adolescence and is a global health concern. Pediatric TBI presents with a bimodal age distribution, with very young children (0-4 years) and adolescents (15-19 years) more commonly injured. Because children's brains are still developing, there is increased vulnerability to the effects of head trauma, which results in entirely different patterns of injury than in adults. Pediatric TBI has a profound and lasting impact on a child's development and quality of life, resulting in long-lasting consequences to physical, cognitive, and emotional development. Chronic issues like learning disabilities, behavioral problems, and emotional disturbances can develop. Early intervention and ongoing support are critical for minimizing these long-term deficits. Many animal models of TBI exist, and each varies significantly, displaying different characteristics of clinical TBI. The neurodevelopment differs in the rodent from the human in timing and effect, so TBI outcomes in the juvenile rodent can thus vary from the human child. The current review compares findings from preclinical TBI work in juvenile and adult rodents to clinical TBI research in pediatric and adult humans. We focus on the four brain regions most affected by TBI: the prefrontal cortex, corpus callosum, hippocampus, and hypothalamus. Each has its unique developmental projections and thus is impacted by TBI differently. This review aims to compare the healthy neurodevelopment of these four brain regions in humans to the developmental processes in rodents.

Factors related to social inferencing performance in moderate-severe, chronic TBI

OBJECTIVE

Following traumatic brain injury (TBI), deficits in social cognition are common. Social inferencing is a crucial component of social cognition that enables an individual to understand the thoughts, feelings, and intentions of a communication partner when this information is not explicitly stated. Existing literature suggests a variety of factors contribute to social inferencing success (e.g. biological sex, executive functioning), yet findings are not conclusive, largely because these factors have been examined in isolation.

METHOD

In this cross-sectional study, stepwise regression with cross validation was used to examine the extent that several theoretically motivated factors were associated with social inferencing (measured by performance on The Awareness of Social Inference Test [TASIT]) in adult participants with TBI (n = 105). Demographic information, executive functioning, aggression, emotional functioning measures, and participation in society were all examined in relation to social inferencing performance.

RESULTS

The findings confirm the importance of higher-level cognitive skills (i.e. executive functioning) in social inferencing, and advance the literature by underlining the potential importance of productive participation in social inferencing performance.

CONCLUSION

This study innovatively highlights factors linked with social inferencing skills and, in doing so, how deficits in social inferencing might manifest in the lives of individuals with TBI.

Apathy and Depression Among People Aging With Traumatic Brain Injury: Relationships to Cognitive Performance and Psychosocial Functioning

OBJECTIVE

Apathy and depression are both common after moderate to severe traumatic brain injury (TBI) and may be especially important to distinguish in older adults with TBI. The authors examined apathy and depression in relation to cognitive performance domains and their potentially unique contribution to psychosocial functioning in this patient population.

METHODS

A total of 106 participants (mean±SD age=64±8 years) with chronic moderate to severe TBI (≥1 year) completed questionnaires assessing severity of apathy (Frontal Systems Behavior Scale-apathy subscale) and depression (Geriatric Depression Scale-15) symptoms, health-related quality of life (HRQoL), and societal participation. Participants also completed neuropsychological tests of episodic memory, processing speed, and executive functioning.

RESULTS

Apathy symptom severity was significantly associated with all cognitive performances in correlations adjusted for the familywise error rate; a relationship with executive functioning remained after controlling for demographic and injury variables. Depression symptom severity was not significantly associated with cognition after statistical correction. Both symptomatologies uniquely contributed to HRQoL. Only depression symptoms contributed to societal participation. On the basis of clinical cutoffs, half the sample had neither depression nor apathy, approximately 25% met criteria for only apathy, and 25% had both apathy and depression. The combined presence of clinical depression and apathy was associated with worse HRQoL and societal participation.

CONCLUSIONS

This is the first study to examine apathy and depression in relation to cognition and psychosocial functioning in an older sample with a history of TBI. Findings suggest that the two syndromes can be dissociated in clinically meaningful ways, which may help to refine psychiatric and behavioral interventions in this vulnerable population.

Cerebral and Peripheral Immune Cell Changes following Rodent Juvenile Traumatic Brain Injury

Traumatic brain injury (TBI) is one of the leading causes of death and disability. TBI is associated with neuroinflammation, but temporal changes in immune and inflammatory signaling following TBI have not been fully elucidated. Furthermore, there have been no previous studies on changes in immune cell populations following TBI via the Closed Head Injury Model of Engineered Rotational Acceleration (CHIMERA). The current study aimed to determine the time course changes to inflammatory marker mRNA expression in the acute period following TBI in juvenile rats and to determine acute changes to brain and circulating immune cell populations. For this study, post-natal day (PND)-30 male Long Evans rats sustained a TBI or Sham TBI and were euthanized at 0, 3, 6, 12, 24, or 96 h post-injury. Prefrontal cortex and hippocampus samples were used to determine mRNA expression changes of inflammatory factors. The mRNA expression of the pro-inflammatory cytokine TNF-α was significantly elevated at 6 h post-injury in both regions evaluated. To evaluate immune cell populations, male Long Evans rats were euthanized at 48 h post-injury, and brain and blood samples were used for cell sorting by marker-specific antibodies. In the peripheral blood, there was an elevation in CD3+ total T cells, CD45R+ total B cells, and CD3+CD4+ helper T cells in the TBI subjects. However, there were no changes to natural killer cells or CD3+CD8+ cytotoxic T cell populations. In the brain, there was a reduction in CD11b/c+ monocytes/macrophages, but no changes in other immune cell populations. At 48 h post-injury, the TBI subjects also demonstrated expansion of the thymic medulla. These changes in the cerebral and blood immune cell populations and thymic medulla expansion may implicate the subacute recovery timeframe as a vulnerable window for the immune system in the pediatric population.

Longitudinal recovery of executive functions and social participation prediction following traumatic brain injury

There is heterogeneity across studies and a lack of knowledge about recovery of EFs over time following traumatic brain injury (TBI). Also, EFs are associated with functional outcome, but there is still a gap in knowledge concerning the association between EFs and social participation following TBI. For this reason, we aim to (1) measure the recovery of the three executive function subcomponents of Miyake's model, namely flexibility, updating and inhibition between the acute phase (T1) and 6 months post TBI (T2) and (2) measure the relationship between EFs and social participation after TBI. Thus, a prospective longitudinal study that included 75 patients with TBI (mild and moderate-severe) and 50 patients with orthopedic injuries (controls) without brain damage was carried out. An extensive EFs test battery was administered at T1 and T2 whereas the Mayo-Portland Adaptability Inventory-4 (MPAI-4) was administered only at T2. In contrast with the controls, both TBI groups improved significantly between T1 and T2 on WMS-III Mental Control test (MC) and the D-KEFS Category Switching Condition of the Verbal Fluency task (SVF). Results also showed a simple time effect for the WAIS-IV Digit span and the Hayling tests. Moreover, there was an association between the SVF test and social participation (MPAI-4) at T2. In conclusion, the MC and SVF tests were found to be the best tools for measuring recovery of EFs following TBI. The SVF test was the most likely measure of EFs to give the neuropsychologist an idea of the patient's social participation.

Methylphenidate Ameliorates Behavioural and Neurobiological Deficits in Executive Function for Patients with Chronic Traumatic Brain Injury

(1) Background: Traumatic brain injury (TBI) often results in cognitive impairments, including in visuospatial planning and executive function. Methylphenidate (MPh) demonstrates potential improvements in several cognitive domains in patients with TBI. The Tower of London (TOL) is a visuospatial planning task used to assess executive function. (2) Methods: Volunteers with a history of TBI (n = 16) participated in a randomised, double-blinded, placebo-controlled, fMRI study to investigate the neurobiological correlates of visuospatial planning and executive function, on and off MPh. (3) Results: Healthy controls (HCs) (n = 18) and patients on placebo (TBI-placebo) differed significantly in reaction time (p < 0.0005) and accuracy (p < 0.0001) when considering all task loads, but especially for high cognitive loads for reaction time (p < 0.001) and accuracy (p < 0.005). Across all task loads, TBI-MPh were more accurate than TBI-placebo (p < 0.05) but remained less accurate than HCs (p < 0.005). TBI-placebo substantially improved in accuracy with MPh administration (TBI-MPh) to a level statistically comparable to HCs at low (p = 0.443) and high (p = 0.175) cognitive loads. Further, individual patients that performed slower on placebo at low cognitive loads were faster with MPh (p < 0.05), while individual patients that performed less accurately on placebo were more accurate with MPh at both high and low cognitive loads (p < 0.005). TBI-placebo showed reduced activity in the bilateral inferior frontal gyri (IFG) and insulae versus HCs. MPh normalised these regional differences. MPh enhanced within-network connectivity (between parietal, striatal, insula, and cerebellar regions) and enhanced beyond-network connectivity (between parietal, thalamic, and cerebellar regions). Finally, individual changes in cerebellar-thalamic (p < 0.005) and cerebellar-parietal (p < 0.05) connectivity with MPh related to individual changes in accuracy with MPh. (4) Conclusions: This work highlights behavioural and neurofunctional differences between HCs and patients with chronic TBI, and that adverse differences may benefit from MPh treatment.

Examining the relationship between head trauma and opioid use disorder: A systematic review

OBJECTIVE

To examine recent literature and determine common clinical risk factors between antecedent traumatic brain injury (TBI) and the following development of opioid misuse and provide a framework for clinical identification of at-risk subjects and evaluate potential treatment implications within this association.

DESIGN

A comprehensive systematic literature search of PubMed was conducted for articles between 2000 and December 2022. Studies were included if the human participant had any head trauma exposure and any chronic opioid use or dependence. After eligibility criteria were applied, 16 studies were assessed for thematic trends.

RESULTS

Opioid use disorder (OUD) risks are heightened in cohorts with head trauma exposed to opioids while in the hospital, specifically with tramadol and oxycodone. Chronic pain was the most common predictor of long-term OUD, and continuous somatic symptoms associated with the TBI can lead to long-term opioid usage. Individuals who present with coexisting psychiatric conditions pose significantly more risk associated with a higher risk of long-term opioid use.

CONCLUSION

Findings indicate that therapists and clinicians must consider a risk profile for persons with TBI and follow an integrated care approach to account for mental health, prior substance misuse, presenting somatic symptoms, and current medication regimen during evaluation.

Disinhibited and angry: Investigating the relationship between social disinhibition and the components of aggression following severe TBI

Social disinhibition and aggression share many similarities. But unlike with aggression, research evidence about social disinhibition following severe traumatic brain injury (TBI) is limited and treatments are missing. Establishing the association between aggression and social disinhibition would facilitate a better conceptualization of these disorders. This study aimed to determine the relationship between social disinhibition and aggression following severe TBI.In this case-control study, 25 individuals with severe TBI and 25 control participants completed the Buss-Perry Aggression Questionnaire (BPAQ), Frontal Systems Behaviour Scale (FrSBe), and Social Disinhibition Interview (SDI).Hierarchical multiple regression analyses revealed that, when controlling for covariates, the inclusion of BPAQ Anger in the model led to a 13% increase in proportion of explained variance of social disinhibition (Adjusted R2 increased from .243 to .363, p < .005). BPAQ Anger was not a significant predictor of SDI scores. Similarly, BPAQ Physical aggression scores did not contribute to the prediction of FrSBe Disinhibition or SDI scores.In conclusion, higher levels of self-reported anger (but no other components of aggression) are associated with higher levels of self-reported social disinhibition. While these findings have potential implications for the treatment of social disinhibition, further research into the possible relationship with aggression should be conducted.

Mentalizing can be Impaired in Patients with Meningiomas Originating in the Anterior Skull Base

OBJECTIVE

Mentalizing is an essential function of our social lives. Impairment of mentalizing due to meningiomas has not received attention because most patients return to their social lives after surgical treatment. We investigated the influence of meningiomas and their surgical resection on mentalizing.

METHODS

Low- and high-level mentalizing were retrospectively examined in 61 patients with meningiomas and 14 healthy volunteers. Mentalizing was assessed using the facial expression recognition test and picture arrangement test of the Wechsler Adult Intelligence Scale, third edition, before and after surgery. We examined the influence of tumor localization on mentalizing and recovery from mentalizing disorders after tumor resection. Voxel-based lesion-symptom mapping was performed to investigate the relationship between impairments in mentalizing and tumor location.

RESULTS

Before surgery, mentalizing was impaired significantly in patients with meningiomas compared to those in the control group (low-level: P = 0.015, high-level: P = 0.011). This impairment was associated with contact between the tumor and frontal lobe (low-level: P = 0.036, high-level: P = 0.047) and was severe in patients with tumors arising in the anterior skull base (low-level: P = 0.0045, high-level: P = 0.043). Voxel-based lesion-symptom mapping revealed that when the basal cortex of the frontal lobe was compressed by the tumor, the risk of impaired mentalizing was high. The region responsible for high-level mentalizing was located deeper than that responsible for low-level mentalizing. After the surgical removal of the tumor, the test scores significantly improved (low-level: P = 0.035, high-level: P = 0.045).

CONCLUSIONS

Mentalizing was impaired by meningiomas arising from the anterior skull base, but it can improve after surgical resection of the tumors.

Driving performance acutely after mTBI among young drivers

OBJECTIVE

Mild traumatic brain injury (mTBI) can impair executive function, learning, and memory, which can negatively impact driving ability. However, little is known how the driving performance of young drivers may be impacted acutely after mTBI. This study aimed to evaluate simulated driving within 96 h of mTBI among young drivers as compared to matched healthy controls, and assess the effects of increased cognitive load on driving performance.

METHODS

Injured young drivers ages 16 to 24 with physician-confirmed mTBI were enrolled from two sites (University of Alabama at Birmingham and Ohio State University) and completed the assessment on a high-fidelity driving simulator within 96 h of injury. Matched healthy controls were young drivers without mTBIs matched with an index mTBI by age, sex, athlete status, and driving experience. Participants drove four scenarios in a 2x2 design: with/without cognitive load and with/without critical events. Linear mixed models were used to compare the driving outcomes between mTBI drivers and healthy controls.

RESULTS

A total of 38 participants were included, with 25 cases and 13 controls. Standard deviation of lateral position, following distance and reaction time were analyzed. The preliminary findings indicated that mTBI drivers tended to maintain more distance to the car in front of them than healthy controls. High cognitive load was associated with slower reaction time regardless of TBI status.

CONCLUSIONS

This study is the first to assess simulated driving performance among young drivers with mTBI acutely post-injury. The findings will have important clinical implications on when young drivers may return to driver post-mTBI and at what conditions. Additional research is warranted to confirm these results.

The impact of frontal lesions after mild to moderate traumatic brain injury on frontal network measures

To investigate the impact of frontal macro-structural lesions on intrinsic network measures, we examined brain network function during resting-state fMRI in patients with frontal lesions in the subacute phase after mild to moderate traumatic brain injury. Additionally, network function was related to neuropsychological performances. 17 patients with frontal lesions, identified on admission CT after mild to moderate trauma, were compared to 30 traumatic brain injury patients without frontal lesions and 20 healthy controls. Three months post-injury, we acquired fMRI scans and neuropsychological assessments (measuring frontal executive functions and information processing speed). Using independent component analysis, the activity of and connectivity between network components (largely located in the prefrontal cortex) and relations with neuropsychological measures were examined and compared across groups. The analysis yielded five predominantly frontal components: anterior and posterior part of the default mode network, left and right frontoparietal network and salience network. No significant differences concerning fMRI measures were found across groups. However, the frontal lesions group performed significantly worse on neuropsychological tests than the other two groups. Additionally, the frontal lesions group showed a significant positive association of stronger default mode network-salience network connectivity with better executive performances. Our findings suggest that, on fMRI level, frontal network measures are not largely affected by frontal lesions following a mild to moderate traumatic brain injury. Yet, patients with damage to the frontal structures did show poorer executive abilities which might to some degree be related to altered frontal network connectivity between the default mode network and salience network.

Psychiatric sequelae of traumatic brain injury - future directions in research

Despite growing appreciation that traumatic brain injury (TBI) is an important public health burden, our understanding of the psychiatric and behavioural consequences of TBI remains limited. These changes are particularly detrimental to a person's sense of self, their relationships and their participation in the wider community, and they continue to have devastating individual and cumulative effects long after TBI. This Review relates specifically to TBIs that confer objective clinical or biomarker evidence of structural brain injury; symptomatic head injuries without such evidence are outside the scope of this article. Common psychiatric, affective and behavioural sequelae of TBI and their proposed underlying mechanisms are outlined, along with a brief overview of current treatments. Suggestions for how scientists and clinicians can work together in the future to address the chasms in clinical care and knowledge are discussed in depth.

Sensitivity and specificity of the INECO frontal screening (IFS) in the detection of patients with traumatic brain injury presenting executive deficits

Executive dysfunction (EF) is a common feature of adult traumatic brain injury (TBI), especially in moderate to severe cases. Assessing EF usually requires the administration of an extensive neuropsychological battery, which is time consuming and expensive. The INECO frontal screening (IFS) is a brief, easy-to-administer screening test which has previously shown to be useful in the detection of executive deficits in different psychiatric and neurological populations. The aim of the present study was to assess the usefulness of the IFS in the detection of executive dysfunction in TBI patients. Twenty-eight TBI patients and thirty-two healthy controls were assessed with a battery that included classical executive tests and the IFS. Our results indicated that with a cutoff score of 26.25 points, the IFS showed good sensitivity and specificity in the detection of executive impairments in TBI patients. It also showed good positive and negative predicted values. Our results suggest that the IFS can be considered a useful tool for identifying executive dysfunction in patients with TBI.

Imaging Findings on Head Computed Tomography Scans in Victims of Intimate Partner Violence

OBJECTIVE

The aim of the study is to analyze the imaging findings and injury patterns seen on head computed tomography (CT) examinations performed on survivors of intimate partner violence (IPV).

METHODS

An institutional review board-approved retrospective analysis of 668 patients reporting IPV to our institution's violence intervention and prevention program between January 2013 and June 2018 identified 40 unique patients with radiological findings visible on head CT. All injuries visible on head CT were analyzed based on the anatomic location and injury type. Demographics, IPV screening at the time of injury, concomitant, prior, and subsequent injuries to the index head injury were also recorded.

RESULTS

Our study cohort had 36 women and 4 men with a mean age at presentation of 43 ± 13 years (mean ± SD), 91 unique injuries with 57 (62.6%) isolated soft tissue injuries, 4 (3.2%) fractures, 13 (14.3%) intra-axial, and 17 (18.7%) extra-axial injuries. Soft tissue injuries and intra-axial injuries occurred most commonly in the frontal region (45.6% and 38.5%), followed by the parietal region (22.8% and 23.1%), while most extra-axial injuries were subdural hematomas (41.2%). Left-sided injuries accounted for 49% (45/91) with 29/91 right-sided (32%) and 17/91 bilateral (19%) injuries. The IPV screening occurred in 44% of injury visits (22/50). Concomitant injuries were seen in 14/50 injury visits (28%), most commonly being in the lower extremity (6/14, 42.9% [% of visits with concomitant injuries]) followed by the upper extremity (5/14, 35.7%), while 52% of visits (26/50) were preceded by prior injuries and 68% of events (34/50) were followed by subsequent injuries.

CONCLUSIONS

Isolated soft tissue swelling is the most common manifestation of IPV on head CT scans with frontoparietal region being the most common site. Synchronous and metachronous injuries are frequent.

The limitations and challenges in the assessment of executive dysfunction associated with real-world functioning: The opportunity of serious games

Nowadays, there is a broad range of methods for detecting and evaluating executive dysfunction ranging from clinical interview to neuropsychological evaluation. Nevertheless, a critical issue of these assessments is the lack of correspondence of the neuropsychological test's results with real-world functioning. This paper proposes serious games as a new framework to improve the neuropsychological assessment of real-world functioning. We briefly discuss the contribution and limitations of current methods of evaluation of executive dysfunction (paper-and-pencil tests, naturalistic observation methods, and Information and Communications Technologies) to inform on daily life functioning. Then, we analyze what are the limitations of these methods to predict real-world performance: (1) A lack of appropriate instruments to investigate the complexity of real-world functioning, (2) the vast majority of neuropsychological tests assess well-structured tasks, and (3) measurement of behaviors are based on simplistic data collection and statistical analysis. This work shows how serious games offer an opportunity to develop more efficient tools to detect executive dysfunction in everyday life contexts. Serious games provide meaningful narrative stories and virtual or real environments that immerse the user in natural and social environments with social interactions. In those highly interactive game environments, the player needs to adapt his/her behavioral performance to novel and ill-structured tasks which are suited for collecting user interaction evidence. Serious games offer a novel opportunity to develop better tools to improve diagnosis of the executive dysfunction in everyday life contexts. However, more research is still needed to implement serious games in everyday clinical practice.

Physiological reactivity at rest and in response to social or emotional stimuli after a traumatic brain injury: A systematic review

Numerous studies have shown that alterations in physiological reactivity (PR) after traumatic brain injury (TBI) are possibly associated with emotional deficits. We conducted a systematic review of these studies that evaluated PR in adults with moderate-to-severe TBI, either at rest or in response to emotional, stressful, or social stimuli. We focused on the most common measures of physiological response, including heart rate (HR), heart rate variability (HRV), respiratory sinus arrhythmia (RSA), electrodermal activity (EDA), salivary cortisol, facial electromyography (EMG), and blink reflex.

Methods

A systematic literature search was conducted across six databases (PsycINFO, Psycarticles, SciencDirect, Cochrane Library, PubMed, and Scopus). The search returned 286 articles and 18 studies met the inclusion criteria.

Results

Discrepancies were observed according to the type of physiological measure. Reduced physiological responses in patients with TBI have been reported in most EDA studies, which were also overrepresented in the review. In terms of facial EMG, patients with TBI appear to exhibit reduced activity of the corrugator muscle and diminished blink reflex, while in most studies, zygomaticus contraction did not show significant differences between TBI and controls. Interestingly, most studies measuring cardiac activity did not find significant differences between TBI and controls. Finally, one study measured salivary cortisol levels and reported no difference between patients with TBI and controls.

Conclusion

Although disturbed EDA responses were frequently reported in patients with TBI, other measures did not consistently indicate an impairment in PR. These discrepancies could be due to the lesion pattern resulting from TBI, which could affect the PR to aversive stimuli. In addition, methodological differences concerning the measurements and their standardization as well as the characteristics of the patients may also be involved in these discrepancies. We propose methodological recommendations for the use of multiple and simultaneous PR measurements and standardization. Future research should converge toward a common methodology in terms of physiological data analysis to improve inter-study comparisons.

Lifetime Traumatic Brain Injury and Cognitive Domain Deficits in Late Life: The PROTECT-TBI Cohort Study

Traumatic brain injury (TBI) causes cognitive impairment but it remains contested regarding which cognitive domains are most affected. Further, moderate-severe TBI is known to be deleterious, but studies of mild TBI (mTBI) show a greater mix of negative and positive findings. This study examines the longer-term cognitive effects of TBI severity and number of mTBIs in later life. We examined a subset (n = 15,764) of the PROTECT study, a cohort assessing risk factors for cognitive decline (ages between 50 and 90 years). Participants completed cognitive assessments annually for 4 years. Cognitive tests were grouped using a principal components analysis (PCA) into working memory, episodic memory, attention, processing speed, and executive function. Lifetime TBI severity and number were retrospectively recalled by participants using the Brain Injury Screening Questionnaire (BISQ). Linear mixed models (LMMs) examined the effect of severity of head injury (non-TBI head strike, mTBI, and moderate-severe TBI) and number of mTBI at baseline and over time. mTBI was considered as a continuous and categorical variable (groups: 0 mTBI, 1 mTBI, 2 mTBIs, 3 mTBIs, and 4+ mTBIs). Of the participants 5725 (36.3%) reported at least one mTBI and 510 (3.2%) at least one moderate-severe TBI, whereas 3711 (23.5%) had suffered at worst a non-TBI head strike and 5818 (32.9%) reported no head injuries. The participants had suffered their last reported head injury an average (standard deviation, SD) of 29.6 (20.0) years prior to the study. Regarding outcomes, there was no worsening in longitudinal cognitive trajectories over the study duration but at baseline there were significant cognitive deficits associated with TBI. At baseline, compared with those without head injury, individuals reporting at least one moderate-severe TBI had significantly poorer attention (B = -0.163, p < 0.001), executive scores (B = -0.151, p = 0.004), and processing speed (B = -0.075, p = 0.033). Those who had suffered at least a single mTBI also demonstrated significantly poorer attention scores at baseline compared with the no head injury group (B = -0.052, p = 0.001). Compared with those with no mTBI, those in the 3 mTBI group manifested poorer baseline executive function (B = -0.149, p = 0.025) and attention scores (B = -0.085, p = 0.015). At baseline, those who had suffered four or more mTBIs demonstrated poorer attention (B = -0.135, p < 0.001), processing speed (B = -0.072, p = 0.009), and working memory (B = -0.052, p = 0.036), compared with those reporting no mTBI. TBI is associated with fixed, dose, and severity-dependent cognitive deficits. The most sensitive cognitive domains are attention and executive function, with approximately double the effect compared with processing speed and working memory. Post-TBI cognitive rehabilitation should be targeted appropriately to domain-specific effects. Significant long-term cognitive deficits were associated with three or more lifetime mTBIs, a critical consideration when counseling individuals post-TBI about continuing high-risk activities.

Disconnection of Network Hubs Underlying the Executive Function Deficit in Patients with Ischemic Leukoaraiosis

BACKGROUND

Cognitive impairment is the most common clinical manifestation of ischemic leukoaraiosis (ILA), but the underlying neurobiological pathways have not been well elucidated. Recently, it was thought that ILA is a "disconnection syndrome". Disorganized brain connectome were considered the key neuropathology underlying cognitive deficits in ILA patients.

OBJECTIVE

We aimed to detect the disruption of network hubs in ILA patients using a new analytical method called voxel-based eigenvector centrality (EC) mapping.

METHODS

Subjects with moderate to severe white matters hyperintensities (Fazekas score ≥3) and healthy controls (HCs) (Fazekas score = 0) were included in the study. The resting-state functional magnetic resonance imaging and the EC mapping approach were performed to explore the alteration of whole-brain network connectivity in ILA patients.

RESULTS

Relative to the HCs, the ILA patients exhibited poorer cognitive performance in episodic memory, information processing speed, and executive function (all ps < 0.0125). Additionally, compared with HCs, the ILA patients had lower functional connectivity (i.e., EC values) in the medial parts of default-mode network (i.e., bilateral posterior cingulate gyrus and ventral medial prefrontal cortex [vMPFC]). Intriguingly, the functional connectivity strength at the right vMPFC was positively correlated with executive function deficit in the ILA patients.

CONCLUSION

The findings suggested disorganization of the hierarchy of the default-mode regions within the whole-brain network in patients with ILA and advanced our understanding of the neurobiological mechanism underlying executive function deficit in ILA.

Milnacipran Ameliorates Executive Function Impairments following Frontal Lobe Traumatic Brain Injury in Male Rats: A Multimodal Behavioral Assessment

Traumatic brain injuries (TBIs) affect more than 10 million patients annually worldwide, causing long-term cognitive and psychosocial impairments. Frontal lobe TBIs commonly impair executive function, but laboratory models typically focus primarily on spatial learning and declarative memory. We implemented a multi-modal approach for clinically relevant cognitive-behavioral assessments of frontal lobe function in rats with TBI and assessed treatment benefits of the serotonin-norepinephrine reuptake inhibitor, milnacipran (MLN). Two attentional set-shifting tasks (AST) evaluated cognitive flexibility via the rats' ability to locate food-based rewards by learning, unlearning, and relearning sequential rule sets with shifting salient cues. Adult male rats reached stable pre-injury operant AST (oAST) performance in 3-4 weeks, then were isoflurane-anesthetized, subjected to a unilateral frontal lobe controlled cortical impact (2.4 mm depth, 4 m/sec velocity) or Sham injury, and randomized to treatment conditions. Milnacipran (30 mg/kg/day) or vehicle (VEH; 10% ethanol in saline) was administered intraperitoneally via implanted osmotic minipumps (continuous infusions post-surgery, 60 μL/h). Rats had a 10-day recovery post-TBI/Sham before performing light/location-based oAST for 10 days and, subsequently, odor/media-based digging AST (dAST) on the last test day (26-27 days post-injury) before sacrifice. Both AST tests revealed significant deficits in TBI+VEH rats, seen as elevated total trials and errors (p < 0.05), which generally normalized in MLN-treated rats (p < 0.05). This first simultaneous dual AST assessment demonstrates oAST and dAST are sufficiently sensitive and robust to detect subtle attentional and cognitive flexibility executive impairments after frontal lobe TBI in rats. Chronic MLN administration shows promise for attenuation of post-TBI executive function deficits, thus meriting further investigation.

The negative influence of chronic alcohol abuse on acute cognitive recovery after a traumatic brain injury

OBJECTIVE

Cognitive recovery after a traumatic brain injury (TBI) may be negatively affected by a prior alcohol use disorder (AUD). This study aims to compare the cognitive recovery of patients who had comorbid TBI and AUD relative to TBI alone and investigate the influence of blood alcohol level (BAL) at hospital admission on this recovery.

METHOD

The sample consisted of 42 patients who had sustained a TBI (mild or moderate) and had an AUD diagnosis (TBI+AUD), and 42 patients who had sustained a TBI alone (TBI). The Brief Cognitive Exam in Traumatology (EXACT), designed to evaluate cognitive functions in the acute phase of TBI was administered (± 2 weeks post-injury).

RESULTS

After controlling for BAL at admission, the TBI+AUD group had a lower EXACT total score compared to the TBI group. The negative influence of age on the results was more pronounced in the TBI+AUD group. The number of intoxicated patients at admission was also higher in this group, although there was no correlation between BAL at admission and cognitive outcome.

CONCLUSION

The presence of an AUD diagnosis seems to exert a greater negative influence on cognitive recovery following a mild/moderate TBI than BAL at admission, especially in older patients.

Experiences of Persons With Executive Dysfunction in Disability Care Using a Social Robot to Execute Daily Tasks and Increase the Feeling of Independence: Multiple-Case Study

Background

Executive functions are essential for independently navigating nearly all of our daily activities. Executive dysfunction often occurs as a result of a neurodevelopmental disorder. Persons with executive dysfunction experience challenges regarding independent execution of daily tasks. Social robots might support persons with executive dysfunction to execute daily tasks and promote their feeling of independence.

Objective

This study aimed to study the impact of interacting with social robot Tessa on goal attainment in the execution of daily tasks and perceived independence of persons with executive dysfunction.

Methods

In this multiple-case study, 18 participant–caregiver couples were followed up while using Tessa in the home environment for 3 months. Goal attainment on independently performing a self-determined goal was measured by the Goal Attainment Scale, and participant–caregiver couples were interviewed about their experience with their interaction with Tessa and how they perceived Tessa’s impact on their independence.

Results

In total, 11 (61%) participants reached their goal after 6 weeks and maintained their goal after 3 months. During the study period, 2 participant–caregiver couples withdrew because of mismatch with Tessa. Participants set goals in the following domains: execution of household tasks; intake of food, water, or medication; being ready in time for an appointment; going to bed or getting out of bed on time; personal care; and exercise. Participants perceived that Tessa increased the feeling of independence by generating more structure, stimulation, and self-direction. Participant–caregiver couples reported that the auditive information provided by Tessa was more effective in coping with executive dysfunction compared to their initial approaches using visual information, and the use of Tessa had a positive impact on their relationship.

Conclusions

This study paid ample time and attention to the implementation of a social robot in daily care practice. The encouraging findings support the use of social robot Tessa for the execution of daily tasks and increasing independence of persons with executive dysfunction in disability care.

Cognitive efficacy and neural mechanisms of music-based neurological rehabilitation for traumatic brain injury

Traumatic brain injury (TBI) causes lifelong cognitive deficits, most often in executive function (EF). Both musical training and music-based rehabilitation have been shown to enhance EF and neuroplasticity. Thus far, however, there is little evidence for the potential rehabilitative effects of music for TBI. Here, we review the core findings from our recent cross-over randomized controlled trial in which a 10-week music-based neurological rehabilitation (MBNR) protocol was administered to 40 patients with moderate-to-severe TBI. Neuropsychological testing and structural/functional magnetic resonance imaging were collected at three time points (baseline, 3 months, and 6 months); one group received the MBNR between time points 1 and 2, while a second group received it between time points 2 and 3. We found that both general EF and set shifting improved after the intervention, and this effect was maintained long term. Morphometric analyses revealed therapy-induced gray matter volume changes most consistently in the right inferior frontal gyrus, changes that correlated with better outcomes in set shifting. Finally, we found changes in the between- and within-network functional connectivity of large-scale resting-state networks after MBNR, which also correlated with measures of EF. Taken together, the data provide evidence for concluding that MBNR improves EF in TBI; also, the data show that morphometric and resting-state functional connectivity are sensitive markers with which to monitor the neuroplasticity induced by the MBNR intervention.

Skill-learning by observation-training with patients after traumatic brain injury

Traumatic brain injury (TBI) is a major cause of death and disability in Western society, and often results in functional and neuropsychological abnormalities. Memory impairment is one of the most significant cognitive implications after TBI. In the current study we investigated procedural memory acquisition by observational training in TBI patients. It was previously found that while practicing a new motor skill, patients engage in all three phases of skill learning–fast acquisition, between-session consolidation, and long-term retention, though their pattern of learning is atypical compared to healthy participants. A different set of studies showed that training by observing a motor task, generally prompted effective acquisition and consolidation of procedural knowledge in healthy participants. The aim of our study was to (i) evaluate the potential benefit of action observation in TBI patients. (ii) Examine the possibility of general improvement in performance between the first (24 h post-training) and second (2 weeks post-training) stage of the study. (iii) Investigate the link between patients’ ability to benefit from observational learning (via performance gains–speed and accuracy) and common measures of injury (such as severity of injury, functional and cognitive measures).

Attaining the recesses of the cognitive space

Existing neuropsychological tests of executive function often manifest a difficulty pinpointing cognitive deficits when these are intermittent and come in the form of omissions. We discuss the hypothesis that two partially interrelated reasons for this failure stem from relative inability of neuropsychological tests to explore the cognitive space and to explicitly take into account strategic and opportunistic resource allocation decisions, and to address the temporal aspects of both behaviour and task-related brain function in data analysis. Criteria for tasks suitable for neuropsychological assessment of executive function, as well as appropriate ways to analyse and interpret observed behavioural data are suggested. It is proposed that experimental tasks should be devised which emphasize typical rather than optimal performance, and that analyses should quantify path-dependent fluctuations in performance levels rather than averaged behaviour. Some implications for experimental neuropsychology are illustrated for the case of planning and problem-solving abilities and with particular reference to cognitive impairment in closed-head injury.

Cortical and Subcortical Alterations and Clinical Correlates after Traumatic Brain Injury

Background: Traumatic brain injury (TBI) often results in persistent cognitive impairment and psychiatric symptoms, while lesion location and severity are not consistent with its clinical complaints. Previous studies found cognitive deficits and psychiatric disorders following TBI are considered to be associated with prefrontal and medial temporal lobe lesions, however, the location and extent of contusions often cannot fully explain the patient′s impairments. Thus, we try to find the structural changes of gray matter (GM) and white matter (WM), clarify their correlation with psychiatric symptoms and memory following TBI, and determine the brain regions that primary correlate with clinical measurements. Methods: Overall, 32 TBI individuals and 23 healthy controls were recruited in the study. Cognitive impairment and psychiatric symptoms were examined by Mini-Mental State Examination (MMSE), Hospital Anxiety and Depression Scale (HADS), and Wechsler Memory Scale-Chinese Revision (WMS-CR). All MRI data were scanned using a Siemens Prisma 3.0 Tesla MRI system. T1 MRI data and diffusion tensor imaging (DTI) data were processed to analyze GM volume and WM microstructure separately. Results: In the present study, TBI patients underwent widespread decrease of GM volume in both cortical and subcortical regions. Among these regions, four brain areas including the left inferior temporal gyrus and medial temporal lobe, supplementary motor area, thalamus, and anterior cingulate cortex (ACC) were highly implicated in the post-traumatic cognitive impairment and psychiatric complaints. TBI patients also underwent changes of WM microstructure, involving decreased fractional anisotropy (FA) value in widespread WM tracts and increased mean diffusivity (MD) value in the forceps minor. The changes of WM microstructure were significantly correlated with the decrease of GM volume. Conclusions: TBI causes widespread cortical and subcortical alterations including a reduction in GM volume and change in WM microstructure related to clinical manifestation. Lesions in temporal lobe may lead to more serious cognitive and emotional dysfunction, which should attract our high clinical attention.

Online and Intellectual Awareness of Executive Functioning in Daily Life among Adolescents with and without ADHD

OBJECTIVE

Executive function deficits (EFD) are a central mechanism underlying negative outcomes in ADHD. This study examined awareness of EFD manifested in "real-time" task performance (Online Awareness) and in general self-knowledge of daily activities, outside the context of a specific task (Intellectual Awareness) among adolescents with and without ADHD.

METHODS

102 adolescents with (n = 52) and without (n = 50) ADHD were administered Weekly Calendar Planning Activity (WCPA) and Behavior Rating Inventory of Executive Function (BRIEF). Parents completed the BRIEF parent version. Awareness was defined using the discrepancy paradigm: performance versus estimation on WCPA for online awareness; self versus parent report on the BRIEF for intellectual awareness.

RESULTS

Adolescents with ADHD overestimated their performance on the WCPA and underestimated their EFD on the BRIEF compared to parent's ratings. The discrepancy scores in both types of awareness were significantly larger among ADHD than controls (p < .005).

CONCLUSIONS

Adolescents with ADHD demonstrate significantly lower rates of online and intellectual awareness of EFD compared to controls.

Cognitive profile of mild traumatic brain injury patients requiring acute hospitalization - A UC davis cognitive screener (UCD-Cog) study

OBJECTIVE

Identification of patients with mTBI at risk for developing persistent-post concussive syndromes should begin during the ED/inpatient evaluation due to frequent lack of post-discharge follow-up. The best method for evaluating cognitive deficits in these acute settings and how to utilize this information to optimize follow-up care is a matter of ongoing research. In this descriptive study, we present the cognitive profile of 214 hospitalized patients with mTBI using a novel cognitive and behavioral screener, the UCD-Cog.

METHOD

A retrospective review of patients with mTBI requiring hospitalization who were enrolled in the UC Davis TBI Registry over the course of 1 year.

RESULTS

Reasoning, executive function, and delayed recall were the most frequently impaired cognitive domains. GCS 13-14 was associated with higher numbers of impaired cognitive domains and frequencies of impairments in domains traditionally associated with post-concussive symptoms. Patients with abnormal UCD-Cog results, regardless of GCS, were recommended higher levels of post-discharge care and supervision.

CONCLUSION

Inpatient cognitive profiles using the UCD-Cog were consistent with evaluations during the subacute/chronic phase of mTBI and supports the clinical utility of acute cognitive screeners for mTBI management. Future studies will determine how the acute cognitive assessments correlate with long-term mTBI outcomes.

Assessment of Executive Function in Everyday Life-Psychometric Properties of the Norwegian Adaptation of the Children's Cooking Task

Background: There are few standardized measures available to assess executive function (EF) in a naturalistic setting for children. The Children's Cooking Task (CCT) is a complex test that has been specifically developed to assess EF in a standardized open-ended environment (cooking). The aim of the present study was to evaluate the internal consistency, inter-rater reliability, sensitivity and specificity, and also convergent and divergent validity of the Norwegian version of CCT among children with pediatric Acquired Brain Injury (pABI) and healthy controls (HCs). Methods: The present study has a cross-sectional design, based on baseline data derived from a multicenter RCT. Seventy-five children with pABI from two university hospitals with parent-reported executive dysfunction and minimum of 12 months since injury/completed cancer therapy, as well as 59 HCs aged 10-17 years, were assessed with CCT using total errors as the main outcome measure. The pABI group completed tests assessing EF (i.e., inhibition, cognitive flexibility, working memory, and planning) on the impairment level within the ICF framework (performance-based neuropsychological tests and the Behavioral Assessment of the Dysexecutive Syndrome for Children), and on the participation level (questionnaires). In addition, they completed tests of intellectual ability, processing speed, attention, learning, and memory. Finally, overall functional outcome (pediatric Glasgow Outcome Scale-Extended) was evaluated for the children with pABI. Results: Acceptable internal consistency and good inter-rater reliability were found for the CCT. Children with pABI performed significantly worse on the CCT than the HCs. The CCT identified group membership, but the sensitivity and specificity were overall classified as poor. Convergent validity was demonstrated by associations between the CCT and performance-based tests assessing inhibition, cognitive flexibility, and working memory, as well as teacher-reported executive dysfunction (questionnaires). Divergent validity was supported by the lack of association with performance-based measures of learning and memory, attention, and verbal intellectual ability. However, there was a moderate association between the CCT and performance-based tests of processing speed. Lastly, better performance on the CCT was associated with a better functional outcome. Conclusion: Our study with a relatively large sample of children with pABI and HC's demonstrated good psychometric properties of the CCT. CCT performance was associated with the overall level of disability and function, suggesting that CCT is related to the level of activity in everyday life and participation in society. Hence, our study suggests that the CCT has the potential to advance the assessment of EF by providing a valid analysis of real-world performance. Nevertheless, further research is needed on larger samples, focusing on predictors of task performance, and evaluating the ability of CCT to detect improvement in EF over time. The patterns of error and problem-solving strategies evaluated by the CCT could be used to inform neuropsychological rehabilitation treatmentand represent a more valid outcome measure of rehabilitation interventions.

The prevalence, characteristics, and psychiatric correlates of traumatic brain injury in incarcerated individuals: an examination in two independent samples

PRIMARY OBJECTIVE

Identify the prevalence, characteristics, and psychological correlates of traumatic brain injury (TBI) among incarcerated individuals.

RESEARCH DESIGN

Three aims: (1) Determine the prevalence and characteristics of TBI in 1469 adults incarcerated in Wisconsin state prisons (1064 men, 405 women); (2) Characterize the relationship between mild TBI and mental illness in a sub-sample of men and women; (3) Reproduce the findings from Aim 1 and Aim 2 in an independent sample of 1015 adults incarcerated in New Mexico state prisons (600 men, 415 women).

METHODS AND PROCEDURES

Standardized TBI assessment with structured clinical interviews and self-report questionnaires.

MAIN OUTCOMES AND RESULTS

Rates of TBI were approximately five times greater than the general population, with a substantially higher rate of TBI caused by assault. In the Wisconsin sample, mild TBI was associated with greater levels of post-traumatic stress disorder (PTSD) among women (but not among men). In the New Mexico sample, TBI of any severity was associated with greater levels of major depressive disorder (MDD) among women (but not among men).

CONCLUSIONS

This study thus provides novel data on TBI and its correlates among individuals incarcerated in state prisons, and highlights a specific treatment need within the prison population.

Selective activation of central thalamic fiber pathway facilitates behavioral performance in healthy non-human primates

Central thalamic deep brain stimulation (CT-DBS) is an investigational therapy to treat enduring cognitive dysfunctions in structurally brain injured (SBI) patients. However, the mechanisms of CT-DBS that promote restoration of cognitive functions are unknown, and the heterogeneous etiology and recovery profiles of SBI patients contribute to variable outcomes when using conventional DBS strategies,which may result in off-target effects due to activation of multiple pathways. To disambiguate the effects of stimulation of two adjacent thalamic pathways, we modeled and experimentally compared conventional and novel 'field-shaping' methods of CT-DBS within the central thalamus of healthy non-human primates (NHP) as they performed visuomotor tasks. We show that selective activation of the medial dorsal thalamic tegmental tract (DTTm), but not of the adjacent centromedian-parafascicularis (CM-Pf) pathway, results in robust behavioral facilitation. Our predictive modeling approach in healthy NHPs directly informs ongoing and future clinical investigations of conventional and novel methods of CT-DBS for treating cognitive dysfunctions in SBI patients, for whom no therapy currently exists.

Prenatal drug exposure and executive function in early adolescence

PURPOSE

Study of the relationship between prenatal cocaine exposure (PCE) and executive function (EF) has yielded inconsistent results. The purpose of the current study is to examine whether PCE, biological sex, environmental risk, and their interaction predicted EF in early adolescence.

METHODS

135 12-year-old adolescents (40.7% with PCE), who were followed prospectively from birth, attempted up to 8 Tower of Hanoi (ToH) puzzle trials of increasing complexity. The number of correctly completed puzzles served as the main outcome measure. Survival analysis was used to examine predictors of the number of successfully completed trials.

RESULTS

As trial difficulty increased, fewer adolescents were able to solve the TOH puzzle. Adolescents from high risk environments and with either prenatal alcohol or prenatal cannabis exposure completed fewer puzzles (p < .05). In addition, a hypothesized 3-way interaction of PCE x sex x environmental risk was found such that cocaine-exposed males with high environmental risk had the worst performance (p < .01).

CONCLUSIONS

The current findings are consistent with prior research indicating that males with PCE may be at particular risk of poorer functioning and highlight the potential importance of examining adolescent's sex and environmental risk as moderators of PCE effects.

Loss of smell in patients with traumatic brain injury is associated with neuropsychiatric behavioral alterations

OBJECTIVE

We sought to identify and correlate the severity of traumatic brain injuries (TBIs) associated with olfactory dysfunction with cognitive and behavioral profiles.

PARTICIPANTS AND SETTING

Patients with TBI undergoing treatment in a specialized neuro-rehabilitation hospital.

DESIGN

Prospective study.

MAIN MEASURES

Glasgow Coma Scale (GCS) at the time of injury and during posttraumatic amnesia. Motor functions were assessed with the Functional Instrument Measure and Disability Rating Scales. The Wechsler Adult Intelligence test was used for neuropsychologic assessment and the Neuropsychiatric Inventory was used to assess behavioral changes. The Barcelona Smell Test-24 was used to study subjective smell loss.

RESULTS

A total of 111 patients with TBI were enrolled (33 females; mean age 32.86 years); 38.73% exhibited smell loss. Patients with no olfactory impairment (OI) had worse TBIs than those with OI (GCS scores 5.65 and 7.74, respectively); no significant differences in cognitive behaviors, such as attention memory, visuoperception, and visuoconstruction, were observed. However, patients with TBI and olfactory dysfunction showed statistically significant alterations in neuropsychiatric behavioral performances such as feeding when compared with patients with TBI without smell loss.

CONCLUSION

Olfactory dysfunction in patients with a TBI correlates with altered neuropsychiatric behavioral performances such as feeding, sleeping, and motor behavior.

The Association of Lifetime and Deployment-Acquired Traumatic Brain Injury With Postdeployment Binge and Heavy Drinking

OBJECTIVE

To investigate associations of lifetime traumatic brain injury (LT-TBI) prior to an index deployment, and/or deployment-acquired TBI (DA-TBI), with postdeployment binge and heavy drinking.

SETTING

Soldiers from 3 Brigade Combat Teams deployed to Afghanistan in 2012.

PARTICIPANTS

A total of 4645 soldiers who participated in the Army STARRS Pre/Post Deployment Study and completed 4 assessments: T0 (1-2 months predeployment), T1 (upon return to United States), T2 (3 months postdeployment), and T3 (9 months postdeployment).

DESIGN

Prospective, longitudinal study controlling for baseline binge drinking.

MAIN MEASURES

Self-reported past month binge drinking (5+ alcoholic beverages on the same day) and past month heavy drinking (binge drinking at least weekly) at T2 and T3.

RESULTS

In total, 34.3% screened positive for LT-TBI, and 19.2% screened positive for DA-TBI. At T2 only, LT-TBI, but not DA-TBI, was associated with increased odds of binge drinking (adjusted odds ratio [AOR] = 1.39, 95% confidence interval [CI]: 1.20-1.60, P < .001) and heavy drinking (AOR = 1.28, 95% CI: 1.09-1.49, P = .007). Among the subgroup with LT-TBI, also having DA-TBI was associated with increased risk of heavy drinking at T3 (AOR = 1.42, 95% CI: 1.03-1.95, P = .047).

CONCLUSION

Routine screening for LT-TBI may help target efforts to prevent alcohol misuse among military members.

Insular Connectivity Is Associated With Self-Appraisal of Cognitive Function After a Concussion

Concussion is associated with acute cognitive impairments, with declines in processing speed and reaction time being common. In the clinical setting, these issues are identified via symptom assessments and neurocognitive test (NCT) batteries. Practice guidelines recommend integrating both symptoms and NCTs into clinical decision-making, but correlations between these measures are often poor. This suggests that many patients experience difficulties in the self-appraisal of cognitive issues. It is presently unclear what neural mechanisms give rise to appraisal mismatch after a concussion. One promising target is the insula, which regulates aspects of cognition, particularly interoception and self-monitoring. The present study tested the hypothesis that appraisal mismatch is due to altered functional connectivity of the insula to frontal and midline structures, with hypo-connectivity leading to under-reporting of cognitive issues and hyper-connectivity leading to over-reporting. Data were collected from 59 acutely concussed individuals and 136 normative controls, including symptom assessments, NCTs and magnetic resonance imaging (MRI) data. Analysis of resting-state functional MRI supported the hypothesis, identifying insular networks that were associated with appraisal mismatch in concussed athletes that included frontal, sensorimotor, and cingulate connections. Subsequent analysis of diffusion tensor imaging also determined that symptom over-reporting was associated with reduced fractional anisotropy and increased mean diffusivity of posterior white matter. These findings provide new insights into the mechanisms of cognitive appraisal mismatch after a concussion. They are of particular interest given the central role of symptom assessments in the diagnosis and clinical management of concussion.

'Investigating longitudinal associations between parent reported sleep in early childhood and teacher reported executive functioning in school-aged children with autism'

Up to 80% of children with autism spectrum disorder (ASD) experience sleep disturbance. Poor sleep impairs executive functioning (EF), a lifelong difficulty in ASD. Evidence suggests EF difficulties in ASD are exacerbated by poor sleep. We examine whether early childhood sleep disturbances are associated with worsening EF trajectories in school-aged children with ASD. A subsample (n=217) from the Pathways in ASD longitudinal study was analyzed. The Children's Sleep Habits Questionnaire captured sleep duration, onset, and night awakenings before age 5 (Mean=3.5years). Metacognition (MI) and Behavioral Regulation (BRI) indices, on the Teacher Behavior Rating Inventory of Executive Functioning, were used to measure cognitive and affective components of EF respectively at four time-points (7.8-11.8years). We applied latent growth curve models to examine associations between sleep and EF, accounting for relevant covariates, including school-age sleep (Mean=6.7years). Sleep traits had different age-related impacts on behavioral regulation, but not metacognition. Longer sleep onset at 3.5 years was associated with a worsening BRI difficulties slope (b=2.07, p<0.04), but conversely associated with lower BRI difficulties at 7.7 years (b=-4.14, p=0.04). A longer sleep onset at 6.7 years was related to higher BRI difficulties at 7.7 years (b=7.78, p<0.01). Longer sleep duration at 6.7 years was associated with higher BRI difficulties at age 7.7 (b=3.15, p=0.01), but subscale analyses revealed shorter sleep duration at age 6.7 was linked to a worsening inhibition slope (b=-0.60, p=0.01). Sleep onset is a robust early correlate of behavior regulation in children with ASD, whereas sleep duration is a later childhood correlate.

Executive Functions of Swedish Counterterror Intervention Unit Applicants and Police Officer Trainees Evaluated With Design Fluency Test

Executive functions (EF) represent higher order top-down mechanisms regulating information processing. While suboptimal EF have been studied in various patient groups, their impact on successful behavior is still not well described. Previously, it has been suggested that design fluency (DF)-a test including several simultaneous EF components mainly related to fluency, cognitive flexibility, and creativity-predicts successful behavior in a quickly changing environment where fast and dynamic adaptions are required, such as ball sports. We hypothesized that similar behaviors are of importance in the selection process of elite police force applicants. To test this hypothesis, we compared elite police force applicants (n = 45) with a control group of police officer trainees (n = 30). Although both groups were better than the norm, the elite police force applicants had a significantly better performance in DF total correct when adjusting for sex and age [F(1,71) = 18.98, p < 0.001]. To understand how this capacity was altered by stress and tiredness, we re-tested the elite police force applicants several days during an extreme field assessment lasting 10 days. The results suggested that there was a lower than expected improvement in DF total correct and a decline in the DF3-subtest that includes a larger component of cognitive flexibility than the other subtests (DF1 and DF2). Although there was a positive correlation between the baseline session and the re-test in DF3 [r(40) = 0.49, p = 0.001], the applicants having the highest scores in the baseline test also displayed the largest percentage decline in the re-test [r(40) = -0.46, p = 0.003]. In conclusion, our result suggests that higher order EF (HEF) that include cognitive flexibility and creativity are of importance in the application for becoming an elite police officer but relatively compromised in a stressful situation. Moreover, as the decline is different between the individuals, the results suggest that applicants should be tested during baseline conditions and during stressful conditions to describe their cognitive capacity fully.

A Histological and Morphometric Assessment of the Adult and Juvenile Rat Livers after Mild Traumatic Brain Injury

Traumatic brain injury (TBI) is one of the most severe problems of modern medicine that plays a dominant role in morbidity and mortality in economically developed countries. Our experimental study aimed to evaluate the histological and morphological changes occurring in the liver of adult and juvenile mildly traumatized rats (mTBI) in a time-dependent model. The experiment was performed on 70 adult white rats at three months of age and 70 juvenile rats aged 20 days. The mTBI was modelled by the Impact-Acceleration Model-free fall of weight in the parieto-occipital area. For histopathological comparison, the samples were taken on the 1st, 3rd, 5th, 7th, 14th, and 21st days after TBI. In adult rats, dominated changes in the microcirculatory bed in the form of blood stasis in sinusoidal capillaries and veins, RBC sludge, and adherence to the vessel wall with the subsequent appearance of perivascular and focal leukocytic infiltrates. In juvenile rats, changes in the parenchyma in the form of hepatocyte dystrophy prevailed. In both groups, the highest manifestation of the changes was observed on 5–7 days of the study. On 14–21 days, compensatory phenomena prevailed in both groups. Mild TBI causes changes in the liver of both adult and juvenile rats. The morphological pattern and dynamics of liver changes, due to mild TBI, are different in adult and juvenile rats.

Resting-State Network Plasticity Induced by Music Therapy after Traumatic Brain Injury

Traumatic brain injury (TBI) is characterized by a complex pattern of abnormalities in resting-state functional connectivity (rsFC) and network dysfunction, which can potentially be ameliorated by rehabilitation. In our previous randomized controlled trial, we found that a 3-month neurological music therapy intervention enhanced executive function (EF) and increased grey matter volume in the right inferior frontal gyrus (IFG) in patients with moderate-to-severe TBI (N = 40). Extending this study, we performed longitudinal rsFC analyses of resting-state fMRI data using a ROI-to-ROI approach assessing within-network and between-network rsFC in the frontoparietal (FPN), dorsal attention (DAN), default mode (DMN), and salience (SAL) networks, which all have been associated with cognitive impairment after TBI. We also performed a seed-based connectivity analysis between the right IFG and whole-brain rsFC. The results showed that neurological music therapy increased the coupling between the FPN and DAN as well as between these networks and primary sensory networks. By contrast, the DMN was less connected with sensory networks after the intervention. Similarly, there was a shift towards a less connected state within the FPN and SAL networks, which are typically hyperconnected following TBI. Improvements in EF were correlated with rsFC within the FPN and between the DMN and sensorimotor networks. Finally, in the seed-based connectivity analysis, the right IFG showed increased rsFC with the right inferior parietal and left frontoparietal (Rolandic operculum) regions. Together, these results indicate that the rehabilitative effects of neurological music therapy after TBI are underpinned by a pattern of within- and between-network connectivity changes in cognitive networks as well as increased connectivity between frontal and parietal regions associated with music processing.

Effects of neurological music therapy on behavioural and emotional recovery after traumatic brain injury: A randomized controlled cross-over trial

Traumatic brain injury (TBI) causes deficits in executive function (EF), as well as problems in behavioural and emotional self-regulation. Neurological music therapy may aid these aspects of recovery. We performed a cross-over randomized controlled trial where 40 persons with moderate-severe TBI received a 3-month neurological music therapy intervention (2 times/week, 60 min/session), either during the first (AB, n = 20) or second (BA, n = 20) half of a 6-month follow-up period. The evidence from this RCT previously demonstrated that music therapy enhanced general EF and set shifting. In the current study, outcome was assessed with self-report and caregiver-report questionnaires performed at baseline, 3-month, 6-month, and 18-month stages. The results showed that the self-reported Behavioural Regulation Index of the Behaviour Rating Inventory of Executive Function (BRIEF-A) improved more in the AB than BA group from baseline to 3-month stage and the effect was maintained in the 6-month follow-up. No changes in mood or quality of life questionnaires were observed. However, a qualitative content analysis of the feedback revealed that many participants experienced the intervention as helpful in terms of emotional well-being and activity. Our results suggest that music therapy has a positive effect on everyday behavioural regulation skills after TBI.

Use of Medical Cannabis to Treat Traumatic Brain Injury

There is not a single pharmacological agent with demonstrated therapeutic efficacy for traumatic brain injury (TBI). With recent legalization efforts and the growing popularity of medical cannabis, patients with TBI will inevitably consider medical cannabis as a treatment option. Pre-clinical TBI research suggests that cannabinoids have neuroprotective and psychotherapeutic properties. In contrast, recreational cannabis use has consistently shown to have detrimental effects. Our review identified a paucity of high-quality studies examining the beneficial and adverse effects of medical cannabis on TBI, with only a single phase III randomized control trial. However, observational studies demonstrate that TBI patients are using medical and recreational cannabis to treat their symptoms, highlighting inconsistencies between public policy, perception of potential efficacy, and the dearth of empirical evidence. We conclude that randomized controlled trials and prospective studies with appropriate control groups are necessary to fully understand the efficacy and potential adverse effects of medical cannabis for TBI.

Octopus Watch Fosters Family Resilience by Enhancing Occupational Engagement for Children with Spina Bifida and/or Hydrocephalus: Pilot Study

BACKGROUND

Children with spina bifida and/or hydrocephalus (SB&/H) often experience difficulties with activities of daily living (ADLs) due to impaired executive functioning, increasing sedentary behaviours. The HeyJoy Octopus watch, a child-friendly icon-based smartwatch could be used as an enabler to promote purposeful ADLs (i.e., goal-orientated ADLs).

OBJECTIVE

to investigate the effectiveness of the Octopus watch in promoting purposeful ADLs for children living with SB&/H (<8 years).

METHODS

Mixed-methods engaging parents and children in four phases: (1) Administered demographic questionnaire, semi-structured interview, childhood executive functioning inventory (CHEXI) and the Canadian occupational performance measure (COPM); focus group one introducing the study, information pack using smartwatch and photovoice data collection methods. (2) Measured baseline movement for four days with smartwatch without using functions. (3) Measured activity for 16-days while using the smartwatch. (4) Re-administered assessments and conducted a second focus group based on photovoice narratives.

RESULTS

movement data recorded for four participants, three of four showed mean activity increase (36%). N-of-1 analyses found one participant showed clear improvement (p = 0.021, r² = 0.28). Mean inhibition decreased by 16.4%, and mean change in COPM performance and satisfaction scores were 2.1 and 2.4, respectively. The photovoice narrative focus group supports findings evidenced with improved daily routines.

CONCLUSIONS

The Octopus watch is an innovative early intervention that can promote purposeful ADLs, fostering family resilience by enhancing occupational engagement. Further research is required.

Mild traumatic brain injury recovery: a growth curve modelling analysis over 2 years

BACKGROUND

An improved understanding of the trajectory of recovery after mild traumatic brain injury is important to be able to understand individual patient outcomes, for longitudinal patient care and to aid the design of clinical trials.

OBJECTIVE

To explore changes in health, well-being and cognition over the 2 years following mTBI using latent growth curve (LGC) modelling.

METHODS

Sixty-one adults with mTBI presenting to a UK Major Trauma Centre completed comprehensive longitudinal assessment at up to five time points after injury: 2 weeks, 3 months, 6 months, 1 year and 2 years.

RESULTS

Persisting problems were seen with neurological symptoms, cognitive issues and poor quality of life measures including 28% reporting incomplete recovery on the Glasgow Outcome Score Extended at 2 years. Harmful drinking, depression, psychological distress, disability, episodic memory and working memory did not improve significantly over the 2 years following injury. For other measures, including the Rivermead Post-Concussion Symptoms and Quality of Life after Brain Injury (QOLIBRI), LGC analysis revealed significant improvement over time with recovery tending to plateau at 3-6 months.

INTERPRETATION

Significant impairment may persist as late as 2 years after mTBI despite some recovery over time. Longitudinal analyses which make use of all available data indicate that recovery from mTBI occurs over a longer timescale than is commonly believed. These findings point to the need for long-term management of mTBI targeting individuals with persisting impairment.

Behavioral responses following repeated bilateral frontal region closed head impacts and fear conditioning in male and female mice

The frontal lobes are among the most vulnerable sites in traumatic brain injuries. In the current study, a balanced 2 × 2 × 2 design (n = 18 mice/group), female and male C57Bl/6J mice received repeated bilateral frontal concussive brain injury (frCBI) and underwent fear conditioning (FC) to assess how injured mice respond to adverse conditions. Shocks received during FC impacted behavior on all subsequent tests except the tail suspension test. FC resulted in more freezing behavior in all mice that received foot shocks when evaluated in subsequent context and cue tests and induced hypoactivity in the open field (OF) and elevated zero maze (EZM). Mice that sustained frCBI learned the FC association between tone and shock. Injured mice froze less than sham controls during context and cue tests, which could indicate memory impairment, but could also suggest that frCBI resulted in hyperactivity that overrode the rodent's natural freezing response to threat, as injured mice were also more active in the OF and EZM. There were notable sex differences, where female mice exhibited more freezing behavior than male mice during FC context and cue tests. The findings suggest frCBI impaired, but did not eliminate, FC retention and resulted in an overall increase in general activity. The injury was characterized pathologically by increased inflammation (CD11b staining) in cortical regions underlying the injury site and in the optic tracts. The performance of male and female mice after injury suggested the complexity of possible sex differences for neuropsychiatric symptoms.

The subcortical basis of outcome and cognitive impairment in TBI: A longitudinal cohort study

OBJECTIVE

To understand how, biologically, the acute event of traumatic brain injury gives rise to a long-term disease, we address the relationship between evolving cortical and subcortical brain damage and measures of functional outcome and cognitive functioning at 6 months after injury.

METHODS

For this longitudinal analysis, clinical and MRI data were collected in a tertiary neurointensive care setting in a continuous sample of 157 patients surviving moderate to severe traumatic brain injury between 2000 and 2018. For each patient, we collected T1- and T2-weighted MRI data acutely and at the 6-month follow-up, as well as acute measures of injury severity (Glasgow Coma Scale), follow-up measures of functional impairment (Glasgow Outcome Scale-extended), and, in a subset of patients, neuropsychological measures of attention, executive functions, and episodic memory.

RESULTS

In the final cohort of 113 subcortical and 92 cortical datasets that survived (blind) quality control, extensive atrophy was observed over the first 6 months after injury across the brain. However, only atrophy within subcortical regions, particularly in the left thalamus, was associated with functional outcome and neuropsychological measures of attention, executive functions, and episodic memory. Furthermore, when brought together in an analytical model, longitudinal brain measurements could distinguish good from bad outcome with 90% accuracy, whereas acute brain and clinical measurements alone could achieve only 20% accuracy.

CONCLUSION

Despite great injury heterogeneity, secondary thalamic pathology is a measurable minimum common denominator mechanism directly relating biology to clinical measures of outcome and cognitive functioning, potentially linking the acute event and the longer-term disease of traumatic brain injury.