Mild Traumatic Brain Research Articles

Chronic Traumatic Encephalopathy: Is Latency in Symptom Onset Explained by Tau Propagation?

Chronic traumatic encephalopathy (CTE) is a neurodegenerative tauopathy associated with repetitive mild brain trauma. CTE, previously termed "dementia pugilistica," has been identified in American football, ice hockey, baseball, rugby and soccer players, boxers, wrestlers, and military personnel exposed to blast and other traumatic brain injuries. There is often a long latency period between an individual's exposure to repetitive brain trauma and the clinical symptoms of CTE. The pathology of CTE is characterized by a progression from isolated focal perivascular hyperphosphorylated tau lesions in the cerebral cortex to a widespread tauopathy that involves diffuse cortical and medial temporal lobe regions. We hypothesize that the spread of tau from focal perivascular lesions to a widespread tauopathy occurs as a result of intraneuronal and intrasynaptic prion-like protein templating, as well as tau secretion and propagation along glymphatic and cerebrospinal fluid pathways.

Feasibility of Home-Based Attention Retraining On People with Mild and Moderate Traumatic Brain Injury

The aim of the study was to assess the feasibility of a 4-week home based attention retraining of people with mild or moderate traumatic brain injury. Purposive sampling was done to choose seven participants with attention deficit with mild or moderate traumatic brain injury as the sample of study. The Intervention consisted of tasks such as cancellation of letters, cancellation of symbols with distracters and dictation. Training in administering the intervention was given for patients as well as their caregivers. A baseline assessment for the above mentioned parameter and post-test assessment (after 5 weeks) were done on the participants to assess the impact of the intervention. The research design was informal experimental design before and after without control group. The post-test scores showed that the home based attention retraining has a positive impact on the attention of the participants. However, this couldn’t be proved statistically because of its small sample size. The involvement of the caregiver as well as the motivation level of the participant was observed to have significant impact on the participants’ performance along with several others. Home- based attention retraining was found to be effective, further rigorous studies with larger sample size and control group is suggested.

Localized cortical chronic traumatic encephalopathy pathology after single, severe axonal injury in human brain

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with repetitive mild impact traumatic brain injury from contact sports. Recently, a consensus panel defined the pathognomonic lesion for CTE as accumulations of abnormally hyperphosphorylated tau (p-tau) in neurons (neurofibrillary tangles), astrocytes and cell processes distributed around small blood vessels at sulcal depths in irregular patterns within the cortex. The pathophysiological mechanism for this lesion is unknown. Moreover, a subset of CTE cases harbors cortical β-amyloid plaques. In this study, we analyzed postmortem brain tissues from five institutionalized patients with schizophrenia and history of surgical leucotomy with subsequent survival of at least another 40 years. Because leucotomy involves severing axons bilaterally in prefrontal cortex, this surgical procedure represents a human model of single traumatic brain injury with severe axonal damage and no external impact. We examined cortical tissues at the leucotomy site and at both prefrontal cortex rostral and frontal cortex caudal to the leucotomy site. For comparison, we analyzed brain tissues at equivalent neuroanatomical sites from non-leucotomized patients with schizophrenia, matched in age and gender. All five leucotomy cases revealed severe white matter damage with dense astrogliosis at the axotomy site and also neurofibrillary tangles and p-tau immunoreactive neurites in the overlying gray matter. Four cases displayed p-tau immunoreactivity in neurons, astrocytes and cell processes encompassing blood vessels at cortical sulcal depths in irregular patterns, similar to CTE. The three cases with apolipoprotein E ε4 haplotype showed scattered β-amyloid plaques in the overlying gray matter, but not the two cases with apolipoprotein E ε3/3 genotype. Brain tissue samples from prefrontal cortex rostral and frontal cortex caudal to the leucotomy site, and all cortical samples from the non-leucotomized patients, showed minimal p-tau and β-amyloid pathology. These findings suggest that chronic axonal damage contributes to the unique pathology of CTE over time.

Polysomnographic Assessment of Sleep Function and Structure in Adults With Mild Traumatic Brain Injury/Concussion

Polysomnographic Assessment of Sleep Function and Structure in Adults With Mild Traumatic Brain Injury/Concussion

Chronic cerebrovascular abnormalities in a mouse model of repetitive mild traumatic brain injury

Primary objective: To investigate the status of the cerebrovasculature following repetitive mild traumatic brain injury (r-mTBI).Research design: TBI is a risk factor for development of various neurodegenerative disorders. A common feature of neurodegenerative disease is cerebrovascular dysfunction which includes alterations in cerebral blood flow (CBF). TBI can result in transient reductions in CBF, with severe injuries often accompanied by varying degrees of vascular pathology post-mortem. However, at this stage, few studies have investigated the cerebrovasculature at chronic time points following repetitive mild brain trauma.Methods and procedures: r-mTBI was delivered to wild-type mice (12 months old) twice per week for 3 months and tested for spatial memory deficits (Barnes Maze task) at 1 and 6 months post-injury. At 7 months post-injury CBF was assessed via Laser Doppler Imaging and, following euthanasia, the brain was probed for markers of cerebrovascular dysfunction and inflammation.Main outcomes and results: Memory impairment was identified at 1 month post-injury and persisted as late as 6 months post-injury. Furthermore, significant immunopathological insult, reductions in global CBF and down-regulation of cerebrovascular-associated markers were observed.Conclusions: These results demonstrate impaired cognitive behaviour alongside chronic cerebrovascular dysfunction in a mouse model of repetitive mild brain trauma.

Subacute posttraumatic complaints and psychological distress in trauma patients with or without mild traumatic brain injury

ObjectiveTo identify the frequency, nature and profile of complaints for trauma patients with and without mild traumatic brain injury (mTBI), and to assess their relation to anxiety and depression. MethodsA prospective cohort study in a level-one trauma centre was conducted. Mild traumatic brain injury patients and trauma controls were approached for participation. Two weeks after injury, The Head Injury Symptom Checklist (HISC) and the Hospital Anxiety and Depression Scale (HADS) were administered. ResultsTwo-hundred seventy two patients with mTBI and 125 TC patients completed the questionnaires. Differences were demonstrated between the two trauma populations on frequency and nature of reported complaints. Ordinal common factor analysis on the mTBI scores yielded three factors: mental distress, physical discomfort, and sensory disbalance, which were all significantly correlated to anxiety and depression scores. Discriminant analyses identified a subset of complaints which could allocate almost 80% of patients to the correct group. ConclusionsPatients with mTBI showed a different pattern of complaints than orthopaedic control patients. A mental distress factor consisting of both somatic and cognitive complaints proved to be most discriminating and showed high correlations with anxiety and depression.

Correlation between venous blood phase values detected by enhanced gradient echo T2 star weighted angiography sequence and neurological severity scale scores in mild and severe traumatic brain injury models of rabbits

Objective To explore the change of venous blood phase values detected by enhanced gradient echo T2 star weighted angiography (ESWAN) sequence in mild and severe traumatic brain injury (TBI) models of rabbits in diverse phases and investigate their association with neurological severity scale (NSS) scores. Methods Fifty-one New Zealand rabbits, which were randomly divided into control group (n= 3) , mild injured group (n=24) , and severe injured group (n=24) by random digital table method, underwent routine MRI and ESWAN sequence at the time points of baseline, 1 h, 6 h, 12 h, 24 h, 48 h, 72 h, 1 week, and 2 weeks after injury (3 rabbits per subgroup) respectively. Blood phase values in veins of interest were recorded. Observation of behavior characteristics and abnormalities, followed by NSS, was executed post injury, and the correlation between venous blood phase values and NSS scores was statistically analyzed. Two independent-samples t-test was applied to compare venous blood phase values of diverse measured veins in each group separately at every time ponits. One-way ANOVA was used to analyze venous blood phase values varying over time of measured vessels in each injured group. Least significant difference t-test was applied to compare blood phase values within the subgroups with each other at each time point. NSS scores of mild and severe injured groups were compared by two independent-samples t-test. Correlations between venous blood phase values and NSS scores in each vein and group was analyzed with Spearman correlation analysis. Results Blood phase values in veins of interest presented an inclination of descending, which was more obvious in severe injured groups than in the mild. Change of venous blood phase values over time featured continuing reduction in earlier phases which reached to the minimum in 24-48h, and then increased gradually, especially in VMV, VLV, DSS, and MDVB (P<0.05). ICV and DCV also showed similar trend. Values of NSS scores in the two group were (15.5 ± 3.1) and (33.2±6.5) respectively (t=3.543, P=0.001). Blood phase values in most of the measured veins correlated with NSS scores (P<0.05) after 6h post injury, especially significant during 24-72h among all the measured veins (P< 0.05). Higher accuracy and sensitivity were presented in the supratentorial or superficial veins compared with subtentorial or profound veins. Conclusions It is feasible to evaluate oxygen saturation of veins after TBI by measuring venous blood phase values on ESWAN images. The method is effective in the assessment of the degree of injury and clinical status, indicating a favorable application prospect. Key words: Brain injuries; Magnetic rsonance imaging; Models, animal

CLINICONEUROLOGICAL AND NEUROPSYCHOLOGICAL ASPECTS OF ACUTE PERIOD OF MILD CRANIAL BRAIN TRAUMA CAUSED BY SHOCK WAVE

Purpose: to study the clinical, neurological, and psychological status of patients at acute period of mild cranial brain trauma caused by shock wave. Material: patients participated in fighting actions in the East of Ukraine, which were treated in neurological department of Military medical clinical centre of Northern region in 2015. Results: authors have revealed some symptoms of sensory disorders in the form of nonspecific sensomotor hemisyndrome and general analgesia. Conclusions: Mild closed cranial brain trauma, caused by shock wave, in its acute period has more severe course than in civilian traumas. The identified symptoms are the result of complex influence of shock wave on the central nervous system and nonspecific structures of brain that subsequently can lead to the vegetative nervous system’s disorders and impairment of higher cortical (mental) functions, and also to adjustment disorders and social maladjustment.

軽症・中等症頭部外傷への対応

軽症・中等症頭部外傷への対応

Insomnia and self-perceived disability in workers with delayed recovery after mild traumatic brain injury/concussion

Insomnia and self-perceived disability in workers with delayed recovery after mild traumatic brain injury/concussion

Exertion Testing in Youth with Mild Traumatic Brain Injury/Concussion

The decision regarding return to activity (RTA) after mild traumatic brain injuries/concussion is one of the most difficult and controversial areas in concussion management, particularly for youth. This study investigated how youth with postconcussion syndrome (PCS) are affected by exertion and whether standardized exertion testing using the McMaster All-Out Progressive Continuous Cycling Test can contribute to clinical decision making for safe RTA. Fifty-four youth (8.5-18.3 yr) with a previously confirmed concussion participated in the study. Each participant performed exertion testing on a cycle ergometer and completed a Postconcussion Symptom scale at the following time points: before exertion (baseline), 5 and 30 min, and 24 h after exertion. A modified Postconcussion Symptom scale was administered at 2-min intervals during exertion. Participants had a mean ± SD symptom duration of 6.3 ± 6.9 months after the most recent concussive injury, with a median of 4.1 months (range, 0.7-35 months). Sixty-three percent of participants had symptoms during exertion testing. Symptom profile (number and severity) significantly affected perception of exertion at 50% peak mechanical power. During acute assessment of symptoms (30-min after exertion), headache (P = 0.39), nausea (P = 0.63), and dizziness (P = 0.35) did not change. However, both the number and severity of symptoms significantly improved over 24 h, with 56.8% of youth showing improvements. The time from the most recent injury had a significant effect on the symptom score at baseline, 30 min after exertion, and 24 h after exertion. Exertion testing has an important role in the evaluation of symptoms and readiness to RTA, particularly in youth who are slow to recover. Overall, controlled exertion seemed to lesson symptoms for most youth.

Neurodegeneration after mild and repetitive traumatic brain injury: Chronic traumatic encepalopathy -

Neurodegeneration after mild and repetitive traumatic brain injury: Chronic traumatic encepalopathy -

Resonance of human brain under head acceleration.

Although safety standards have reduced fatal head trauma due to single severe head impacts, mild trauma from repeated head exposures may carry risks of long-term chronic changes in the brain's function and structure. To study the physical sensitivities of the brain to mild head impacts, we developed the first dynamic model of the skull-brain based on in vivo MRI data. We showed that the motion of the brain can be described by a rigid-body with constrained kinematics. We further demonstrated that skull-brain dynamics can be approximated by an under-damped system with a low-frequency resonance at around 15 Hz. Furthermore, from our previous field measurements, we found that head motions in a variety of activities, including contact sports, show a primary frequency of less than 20 Hz. This implies that typical head exposures may drive the brain dangerously close to its mechanical resonance and lead to amplified brain-skull relative motions. Our results suggest a possible cause for mild brain trauma, which could occur due to repetitive low-acceleration head oscillations in a variety of recreational and occupational activities.

An Examination of the Word Memory Test as a Measure of Memory

This study examined the utility of the Word Memory Test (WMT) as a measure of verbal episodic memory by comparing select WMT subtests to the California Verbal Learning Test (CVLT) First and Second Editions (CVLT-II) across two samples. Correlations between the WMT and CVLT/CVLT-II subtests were statistically significant in the expected direction. Effect sizes were examined to assess the degree to which the WMT memory subtests and the CVLT First Edition subtests discriminated between groups of people who would be expected to differ from each other in verbal memory abilities. Comparison groups included cases of mild, moderate, and severe traumatic brain injury, mixed neurological patients, healthy adult controls, and patients with possible early dementia. Once invalid data were removed by studying only those who passed performance validity testing, it was found that the effect sizes between these groups were comparable. The WMT, CVLT, and CVLT-II were found to discriminate to about the same degree between people differing from each other in age, intelligence levels, and gender. Based on these data from a total sample of more than 3,000 cases, it is concluded that select WMT subtests are commensurate with the CVLT subtests as measures of memory within primarily disability-seeking samples.

The Validation of the Interactive Metronome: A Pilot Study Prior to Implementation for Post Deployment Service Members

The purpose of this study was to validate the protocols created for the Interactive Metronome TM (IM) used in conjunction with the TRX® System for returning post deployment service members diagnosed with mild traumatic brain and/or Post-Traumatic Stress Disorder. This was done using a pilot population similar in age and physical status as active duty military, but within a college setting. The pre-established protocols were pilot tested on two male and two female participants. The data collected was from the IM Long Form, Nine Hole Peg Test, Canadian Occupational Performance Model and the Test of Everyday Attention. In a comparative analysis of pre- and post- status it was determined that the IM along with TRX® system would potentially benefit returning post deployment service members using this series of treatment interventions.

A CASE REPORT OF NEUROLOGICAL IMPROVEMENT FOLLOWING MILD HEAD TRAUMA IN AN 11 YEAR OLD GIRL USING MULTI-MODAL CONSERVATIVE THERAPIES

Event Abstract Back to Event A CASE REPORT OF NEUROLOGICAL IMPROVEMENT FOLLOWING MILD HEAD TRAUMA IN AN 11 YEAR OLD GIRL USING MULTI-MODAL CONSERVATIVE THERAPIES Gregory F. Ploger1* 1 Carrick Institute for Graduate Studies, United States Background: An athletic 11 year old female lost consciousness after a backward fall. After 14 months, she still suffered intense headaches (3 per week) with nausea, photofobia, diplopia, astenia, difficulty concentrating and reading, and “fogginess”. She showed poor gaze holding, pursuits with decreased gain and multiple intrusions, saccades that were hypermetric to the right, hypometric to the left, with increased latencies and head movements. TrailsA and B were 52 and 90 seconds, respectively. Methods: Specific eye exercises, vestibular rehabilitation, and somatosensory exercises were administered, then checked for efficacy over a 2 hour period using changes in profiles of saccadic position, velocity and latency as parameters. The patient was given exercises to perform at home. Saccades were re-evaluated periodically and exercises modified accordingly. Results: After three months, gaze holding, pursuits and saccades were normalized, the patient was virtually headache-free (1/month) and reported no difficulty in concentrating or reading, nor fogginess, nor light sensitivity. TrailsA and B improved by 54% and 51%, respectively. Saccadic latencies remained slightly above 200 msec, but velocity and position profiles were significantly improved. Conclusion: Specific, multi-modal conservative therapy may be effective in improving neurologic function following mild brain trauma. More research is needed to establish to what extent changes in saccades reflect improved overall central integrity. Conflict of Interest: This author declares that this research was conducted in the absence of any financial relationships that could be construed as a potential conflict of interest. Keywords: Cerebral concussion, Concussion-mild, Rehabilitation, Vestibular Rehabilitation, Saccades, gaze stability, Saccadic eye movements Conference: International Symposium on Clinical Neuroscience: TBI and Neurodegeneration, Orlando, Florida, United States, 10 Dec - 14 Dec, 2015. Presentation Type: Poster Presentation Topic: Case Reports for Poster Presentation Citation: Ploger GF (2015). A CASE REPORT OF NEUROLOGICAL IMPROVEMENT FOLLOWING MILD HEAD TRAUMA IN AN 11 YEAR OLD GIRL USING MULTI-MODAL CONSERVATIVE THERAPIES. Front. Neurol. Conference Abstract: International Symposium on Clinical Neuroscience: TBI and Neurodegeneration. doi: 10.3389/conf.fneur.2015.58.00073 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 11 Oct 2015; Published Online: 02 Nov 2015. * Correspondence: Dr. Gregory F Ploger, Carrick Institute for Graduate Studies, Cape Canaveral, FL, United States, gregory.ploger@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Gregory F Ploger Google Gregory F Ploger Google Scholar Gregory F Ploger PubMed Gregory F Ploger Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Complexin2 modulates working memory-related neural activity in patients with schizophrenia.

The specific contribution of risk or candidate gene variants to the complex phenotype of schizophrenia is largely unknown. Studying the effects of such variants on brain function can provide insight into disease-associated mechanisms on a neural systems level. Previous studies found common variants in the complexin2 (CPLX2) gene to be highly associated with cognitive dysfunction in schizophrenia patients. Similarly, cognitive functioning was found to be impaired in Cplx2 gene-deficient mice if they were subjected to maternal deprivation or mild brain trauma during puberty. Here, we aimed to study seven common CPLX2 single-nucleotide polymorphisms (SNPs) and their neurogenetic risk mechanisms by investigating their relationship to a schizophrenia-related functional neuroimaging intermediate phenotype. We examined functional MRI and genotype data collected from 104 patients with DSM-IV-diagnosed schizophrenia and 122 healthy controls who participated in the Mind Clinical Imaging Consortium study of schizophrenia. Seven SNPs distributed over the whole CPLX2 gene were tested for association with working memory-elicited neural activity in a frontoparietal neural network. Three CPLX2 SNPs were significantly associated with increased neural activity in the dorsolateral prefrontal cortex and intraparietal sulcus in the schizophrenia sample, but showed no association in healthy controls. Since increased working memory-related neural activity in individuals with or at risk for schizophrenia has been interpreted as 'neural inefficiency,' these findings suggest that certain variants of CPLX2 may contribute to impaired brain function in schizophrenia, possibly combined with other deleterious genetic variants, adverse environmental events, or developmental insults.

Spotlight on the August 5 Issue

This highly powered longitudinal study investigated the predictive value of 2 peripheral markers of inflammation for later cognitive decline. The authors examined the association between interleukin-6 (IL-6) and C-reactive protein (CRP) measured in midlife (participants aged 56 years at the start of cognitive testing) and subsequent cognitive decline. Elevated IL-6 but not CRP in midlife predicted cognitive decline. Results suggest that inflammatory markers are associated with cognition in both cross-sectional and longitudinal associations. See p. 486; Editorials, pp. 478 and 480 The authors reported a longitudinal MRI investigation using diffusion tensor imaging in a large cohort of mildly injured patients and assessed the role that diffuse axonal injury plays in acquired cognitive deficits following mild traumatic brain …

Contrast-Enhanced FLAIR (Fluid-Attenuated Inversion Recovery) for Evaluating Mild Traumatic Brain Injury

PurposeTo evaluate whether adding a contrast-enhanced fluid-attenuated inversion recovery (FLAIR) sequence to routine magnetic resonance imaging (MRI) can detect additional abnormalities in the brains of symptomatic patients with mild traumatic brain injury.Materials and MethodsFifty-four patients with persistent symptoms following mild closed head injury were included in our retrospective study (M∶F = 32∶22, mean age: 59.8±16.4, age range: 26–84 years). All MRI examinations were obtained within 14 days after head trauma (mean: 3.2±4.1 days, range: 0.2–14 days). Two neuroradiologists recorded (1) the presence of traumatic brain lesions on MR images with and without contrast-enhanced FLAIR images and (2) the pattern and location of meningeal enhancement depicted on contrast-enhanced FLAIR images. The number of additional traumatic brain lesions diagnosed with contrast-enhanced FLAIR was recorded. Correlations between meningeal enhancement and clinical findings were also evaluated.ResultsTraumatic brain lesions were detected on routine image sequences in 25 patients. Three additional cases of brain abnormality were detected with the contrast-enhanced FLAIR images. Meningeal enhancement was identified on contrast-enhanced FLAIR images in 9 cases while the other routine image sequences showed no findings of traumatic brain injury. Overall, the additional contrast-enhanced FLAIR images revealed more extensive abnormalities than routine imaging in 37 cases (p<0.001). In multivariate logistic regression analysis, subdural hematoma and posttraumatic loss of consciousness showed a significant association with meningeal enhancement on contrast-enhanced FLAIR images, with odds ratios 13.068 (95% confidence interval 2.037 to 83.852), and 15.487 (95% confidence interval 2.545 to 94.228), respectively.ConclusionMeningeal enhancement on contrast-enhanced FLAIR images can help detect traumatic brain lesions as well as additional abnormalities not identified on routine unenhanced MRI. Therefore contrast-enhanced FLAIR MR imaging is recommended when a contrast MR study is indicated in a patient with a symptomatic prior closed mild head injury.

Differential learning and memory performance in OEF/OIF veterans for verbal and visual material.

Memory complaints are particularly salient among veterans who experience combat-related mild traumatic brain injuries and/or trauma exposure, and represent a primary barrier to successful societal reintegration and everyday functioning. Anecdotally within clinical practice, verbal learning and memory performance frequently appears differentially reduced versus visual learning and memory scores. We sought to empirically investigate the robustness of a verbal versus visual learning and memory discrepancy and to explore potential mechanisms for a verbal/visual performance split. Participants consisted of 103 veterans with reported history of mild traumatic brain injuries returning home from U.S. military Operations Enduring Freedom and Iraqi Freedom referred for outpatient neuropsychological evaluation. Findings indicate that visual learning and memory abilities were largely intact while verbal learning and memory performance was significantly reduced in comparison, residing at approximately 1.1 SD below the mean for verbal learning and approximately 1.4 SD below the mean for verbal memory. This difference was not observed in verbal versus visual fluency performance, nor was it associated with estimated premorbid verbal abilities or traumatic brain injury history. In our sample, symptoms of depression, but not posttraumatic stress disorder, were significantly associated with reduced composite verbal learning and memory performance. Verbal learning and memory performance may benefit from targeted treatment of depressive symptomatology. Also, because visual learning and memory functions may remain intact, these might be emphasized when applying neurocognitive rehabilitation interventions to compensate for observed verbal learning and memory difficulties.