Analysis Of Traumatic Brain Injury Research Articles

Federated Convolutional Neural Networks for Predictive Analysis of Traumatic Brain Injury: Advancements in Decentralized Health Monitoring

Federated Convolutional Neural Networks for Predictive Analysis of Traumatic Brain Injury: Advancements in Decentralized Health Monitoring

Abstract 372: Age-Dependent Effect of Trauma Center Transport on Survival Outcomes Among Severe Trauma Patients: Nationwide Observational Study

Introduction: Previous studies showed that the prognosis for severe trauma patients is better after transport to trauma centers compared to non-trauma centers. However, the benefit from transport to trauma centers may differ according to age group. This study aimed to evaluate the age-dependent effect of trauma center transport on survival outcomes among severe trauma patients. Methods: A cross-sectional study using the Korean national emergency medical service (EMS) based on Severe Trauma Registry in 2018-2019 was conducted. EMS-treated trauma patients whose injury severity score was above or equal to 16, and who were not out-of-hospital cardiac arrest or death on arrival were included. Patients were classified into 3 groups: pediatrics (age <19), working age (age 19-65), and elderly (age>65). The primary outcome was in-hospital mortality. Multivariable logistic regression analysis was conducted to evaluate the effect of trauma center transport on outcome after adjusting age, sex, comorbidity, mechanism of injury, Revised Trauma Score, and Injury Severity Score. All analysis was stratified according to the age group, and subgroup analysis for traumatic brain injury was also conducted. Results: Overall, a total of 10,511 patients were included in the study, and the number of patients in each age group was 488 in pediatrics, 6,812 in working age, and 3,211 in elderly, respectively. The adjusted odds ratio (95% confidence interval [CI]) of trauma center transport on in-hospital mortality were 0.76 (95% CI, 0.43-1.32) in pediatrics, 0.78 (95% CI, 0.68-0.90) in working age, 0.71(95% CI, 0.60-0.85) in elderly, respectively. In the subgroup analysis of traumatic brain injury, the benefit from trauma center transport was observed only in elderly group. Conclusion: We found the age-dependent effect of trauma center transport in severe trauma patients. There was no beneficial effect of trauma center transport in pediatric group. Further research is warranted to evaluate and develop the response system for pediatric severe trauma patients in Korea.

Sex-Specific Human, Agent, and Environment-Related Interactions in Traumatic Brain Injury: Utility of The Haddon Matrix

<h3>Research Objectives</h3> To explore sex differences in the Host, the Agent, and the Environment utilizing computational analysis of traumatic brain injury (TBI) events. <h3>Design</h3> The retrospective population-based study utilized province-wide population-based decade-long health administrative data collected through the routine operation of the publicly funded health system in Ontario, Canada. <h3>Setting</h3> We used a previously established cohort of patients discharged between the fiscal years 2007/2008 and 2015/2016 from acute care and from the emergency department (ED) with diagnoses of TBI. <h3>Participants</h3> We drew upon health records of 235,003 unique patients (57% male) with TBI and the same number of reference patients without TBI, who were individually matched based on sex, age, place of residence, and income level, to organize factors associated with the TBI event. We dissected complex and multidimensional TBI event data by exploiting data mining and information visualization methods in male and female patients separately. We adopted concepts of the Haddon Matrix (Human, Agent, Environment) to organize injury event factors and compare TBI events of male and female patients. <h3>Interventions</h3> Not applicable. <h3>Main Outcome Measures</h3> Sex differences in the health status of the Host, the Agent, and the Environment at the TBI event phase. <h3>Results</h3> Based on perceived similarities, the computational technique detected 35 injury event-related factors, allowing observation of a set of definable patterns within the Host, the Agent, and the Environment. We uncovered significant sex-based differences in Host, Agent, and Environment patterns. We found that the Host's health status is of great importance to injury severity, and the Agent and the Environment have implications for external causes of injury. <h3>Conclusions</h3> Study findings support the utility of computational data mining in examining patterns of information within the TBI event. <h3>Author(s) Disclosures</h3> Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health (NIH) under Award Number R21HD089106 and the National Institute Of Neurological Disorders And Stroke of the NIH under Award Number R01NS117921 and partially by Canada Research Chair Programs.

Impact of Frailty Risk on Adverse Outcomes after Traumatic Brain Injury: A Historical Cohort Study.

We evaluated the utility of the Hospital Frailty Risk Score (HFRS) as a predictor of adverse events after hospitalization in a retrospective analysis of traumatic brain injury (TBI). This historical cohort study analyzed the data of patients hospitalized with TBI between April 2014 and August 2020 who were registered in the JMDC database. We used HFRS to classify the patients into the low- (HFRS < 5), intermediate- (HFRS5-15), and high- (HFRS > 15)-frailty risk groups. Outcomes were the length of hospital stay, the number of patients with Barthel Index score ≥ 95 on, Barthel Index gain, and in-hospital death. We used logistic and linear regression analyses to estimate the association between HFRS and outcome in TBI. We included 18,065 patients with TBI (mean age: 71.8 years). Among these patients, 10,139 (56.1%) were in the low-frailty risk group, 7388 (40.9%) were in the intermediate-frailty risk group, and 538 (3.0%) were in the high-frailty risk group. The intermediate- and high-frailty risk groups were characterized by longer hospital stays than the low-frailty risk group (intermediate-frailty risk group: coefficient 1.952, 95%; confidence interval (CI): 1.117−2.786; high-frailty risk group: coefficient 5.770; 95% CI: 3.160−8.379). The intermediate- and high-frailty risk groups were negatively associated with a Barthel Index score ≥ 95 on discharge (intermediate-frailty risk group: odds ratio 0.645; 95% CI: 0.595−0.699; high-frailty risk group: odds ratio 0.221; 95% CI: 0.157−0.311) and Barthel Index gain (intermediate-frailty risk group: coefficient −4.868, 95% CI: −5.599−−3.773; high-frailty risk group: coefficient −19.596, 95% CI: −22.242−−16.714). The intermediate- and high-frailty risk groups were not associated with in-hospital deaths (intermediate-frailty risk group: odds ratio 0.901; 95% CI: 0.766−1.061; high-frailty risk group: odds ratio 0.707; 95% CI: 0.459−1.091). We found that HFRS could predict adverse outcomes during hospitalization in TBI patients.

Topological features dictate the mechanics of the mammalian brains

Understanding brain mechanics is crucial in the study of pathologies involving brain deformations such as tumor, strokes, or in traumatic brain injury. Apart from the intrinsic mechanical properties of the brain tissue, the topology and geometry of the mammalian brains are particularly important for its mechanical response. We use computational methods in combination with geometric models to understand the role of these features. We find that the geometric quantifiers such as the gyrification index play a fundamental role in the overall mechanical response of the brain. We further demonstrate that topological diversity in brain models is more important than differences in mechanical properties: Topological differences modify not only the stresses and strains in the brain but also its spatial distribution. Therefore, computational brain models should always include detailed geometric information to generate accurate mechanical predictions. These results suggest that mammalian brain gyrification acts as a damping system to reduce mechanical damage in large-mass brain mammals. Our results are relevant in several areas of science and engineering related to brain mechanics, including the study of tumor growth, the understanding of brain folding, and the analysis of traumatic brain injuries.

Clinical and epidemiological analysis of severe traumatic brain injury: the role of nutritional support to the injured with a prolonged state of impaired consciousness

Relevance. Patients with prolonged impaired consciousness due to traumatic brain injury are the most difficult category of patients in inpatient medical rehabilitation units. Despite the experience gained in managing this complex category of patients, the problem of nutrition status and trophological insufficiency, as well as practical issues regarding the organization of optimal nutrition at this stage of medical rehabilitation remain unresolved.Intention. To study the role of nutritional support for patients with long-term impaired consciousness on the basis of a clinical and epidemiological analysis of severe traumatic brain injury.Methodology.The data of an epidemiological analysis of traumatic brain injuries and features of ongoing nutritional support in patients with long-term impaired consciousness are presented, based on a study of domestic and foreign publications from 2005 to 2019.Results and Discussion. Timely and adequate nutritional support optimizes the structural-functional and metabolic systems of the body, adaptive reserves interfere with rapidly progressive depletion and chronic catabolic processes, contribute to positive changes in the functional state of the brain, reduce infectious complications, and increase the effectiveness of rehabilitation measures and the rate of recovery of consciousness.Conclusion. The analysis revealed the ambiguity of the interpreted data on clinical recommendations and approaches to the use of nutritional support in patients with long-term impaired consciousness due to traumatic brain injury. Considering the fact that in most cases such patients need continuous long-term comprehensive rehabilitation measures, accompanied by significant energy costs of the body, an essential component of the rehabilitation process, in our opinion, is the inclusion of adequate nutritional support that prevents fast-progressing exhaustion and chronic catabolic processes. In this regard, such an urgent task is to optimize the algorithms of nutritional support in patients with long-term impaired consciousness after a traumatic brain injury, the solution of which will improve the functional state of the brain and, therefore, the rehabilitation prognosis and quality of their life.

Intracranial pressure-based validation and analysis of traumatic brain injury using a new three-dimensional finite element human head model.

Traumatic brain injuries are life-threatening injuries that can lead to long-term incapacitation and death. Over the years, numerous finite element human head models have been developed to understand the injury mechanisms of traumatic brain injuries. Many of these models are erroneous and used ellipsoidal or spherical geometries to represent brain. This work is focused on the development of high-quality, comprehensive three-dimensional finite element human head model with accurate representation of cerebral sulci and gyri structures in order to study traumatic brain injury mechanisms. Present geometry, predicated on magnetic resonance imaging data consist of three rudimentary components, that is, skull, cerebrospinal fluid with the ventricular system, and the soft tissues comprising the cerebrum, cerebellum, and brain stem. The brain is modeled as a hyperviscoelastic material. Meshed model with 10 nodes modified tetrahedral type element (C3D10M) is validated against two cadaver-based impact experiments by comparing the intracranial pressures at different locations of the head. Our results indicate a better agreement with cadaver results, specifically for the case of frontal and parietal intracranial pressure values. Existing literature focuses mostly on intracranial pressure validation, while the effects of von Mises stress on brain injury are not analyzed in detail. In this work, a detailed interpretation of neurological damage resulting from impact injury is performed by analyzing von Mises stress and intracranial pressure distribution across numerous segments of the brain. A reasonably good correlation with experimental data signifies the robustness of the model for predicting injury mechanisms based on clinical predictions of injury tolerance criteria.

Cognitive and Motor Recovery and Predictors of Long-Term Outcome in Patients With Traumatic Brain Injury

ObjectivesTo explore the patterns of cognitive and motor recovery at 4 time points from admission to 9 months after discharge from inpatient rehabilitation (IR) and to investigate the association of therapeutic factors and conditions before and after discharge with long-term outcomes. DesignSecondary analysis of traumatic brain injury (TBI) and practice-based evidence dataset. SettingIR in Ontario, Canada. ParticipantsPatients with TBI consecutively admitted for IR between 2008 and 2011 who had data available from admission to 9 months after discharge (N=85). InterventionsNot applicable. Main Outcome MeasureFIM-Rasch cognitive and motor scores at admission, discharge, 3 months after discharge, and 9 months after discharge. ResultsCognitive and motor recovery showed similar patterns of improvement with recovery up to 3 months but no significant change from 3 to 9 months. Having fewer postdischarge health conditions was associated with better long-term cognitive scores (95% confidence interval, -13.06 to -1.2) and added 9.9% to the explanatory power of the model. More therapy time in complex occupational therapy activities (95% confidence interval, .02 to .09) and fewer postdischarge health conditions (95% confidence interval, -19.5 to -3.8) were significant predictors of better long-term motor function and added 14.3% and 7.2% to the explanatory power of the model, respectively. ConclusionResults of this study inform health care providers about the influence of the timing of IR on cognitive and motor recovery. In addition, it underlines the importance of making patients and families aware of residual health conditions following discharge from IR.

Towards Identification of Correspondence Rules to Relate Traumatic Brain Injury in Different Species.

Traumatic brain injury analysis in humans is exceedingly difficult due to the intrusive methods by which data can be collected; thus, many researchers commonly implement animal surrogates. However, ethical concerns and cost limit the scope of these tests on animal subjects too. Computational models, which provide an alternative method to data collection, are not constrained by these concerns and are able to generate significant amounts of data in relatively short time. This paper shows how the data generated from models of a human and pig head can be used towards developing interspecies correspondence rules for blast overpressure effects. The blast overpressure is simulated using an explosive of known weight and standoff distance and injury is evaluated using criteria in published literature. Results indicate that equivalent blasts in the human and pig produce significantly different injuries, and when equating total injured brain volume, the locations of injury in the brain vary between the species. Charge weight and total injured brain volume are related using a linear regression of the data such that a known injury in the pig or known blast can be used to predict injury or the blast experienced by a human, thus creating a correspondence between the species.

Impact of helmet use in equestrian-related traumatic brain injury: a matched-pairs analysis

Purpose: Traumatic brain injury is an important health concern in equestrian sports. Nevertheless, the use of safety helmets, especially in recreational riding, is reported to be rare. The purpose of this study was to perform the first matched-pairs analysis of traumatic brain injury with regard to the use of helmets.Materials and methods: In a multicenter retrospective database analysis 40 patients (mean age: 35 ± 17.13 years; 34 female & 6 male) were combined in 20 matched pairs based on age group, gender and trauma mechanism. Admission trauma computed tomography was qualitatively analyzed for the presence or absence of fractures or intracranial hemorrhage. Quantitatively, in patients with intracranial hemorrhage dedicated volumetry of the blood volume was performed. Odds ratio and relative risk were calculated for the endpoints fractures and intracranial hemorrhage. Crude risk ratio and lesion volume differences between helmeted and unhelmeted riders were compared.Results: Concerning skull fractures, in this cohort 6 patients (85.7% of all patients with fractures) did not wear a helmet and only one (14.3%) wore a helmet (p = .068).and fractures were considered more complex in the unhelmeted subgroup. Intracranial hemorrhage occurred significantly more often in the unhelmeted subgroup (10 vs. 2; p = .008). Moreover, the total lesion volume with 19.31 ± 23.93ml in the unhelmeted subgroup, presenting with intracranial hemorrhage, was significantly higher than in the control group (0.65 ± 0.35ml; p = .002). Odds ratios were 9 for intracranial hemorrhage (p = .014) and 8.14 for skull fractures without helmet (p = .09). Altogether, the relative risk for intracranial bleeding for unhelmeted riders was 5-fold higher and the relative risk reduction was 96% by wearing a safety helmet.Conclusions: Under consideration of comparable trauma mechanisms, horseback riders that do not wear a safety helmet are at risk to suffer significantly more severe brain injury than helmeted riders. Therefore, safety helmets are recommendable for all horseback riders.

A biomechanical analysis of traumatic brain injury for slips and falls from height

Background Falls are a common cause of morbidity and mortality in society, particularly among the aged and young. There has been research to describe the epidemiology of these types of events, but to date there has been few correlations of clinical brain injury outcomes and metrics used in biomechanical research; parameters often used to help develop protective devices and environments. The purpose of this research was to examine the kinematic characteristics of falls from standing and higher heights in an effort to understand how clinical brain injury is predicted by biomechanical injury metrics. Methods Computer simulations of nine traumatic brain injury events from falling were conducted to determine the biomechanical metrics associated with each injury case. Results Many of the impacts were to the occipital region of the head, as would be expected from backward falls or from slipping from ladders. These falls resulted in low rotational acceleration values and high linear accelerations, suggesting linear acceleration may be an important characteristic of this injury mechanism. In addition, even though each case resulted in severe head injury, the HIC15 (Head Injury Criterion) values did not consistently predict injury when the kinematic output was lower than 300 g. This result suggests that HIC15 may have limited value as a predictor for high energy short duration direct impacts to the head. The results supported a relationship between fall height and duration of loss of consciousness, with the higher fall heights producing longer times of unconsciousness. Conclusion Linear acceleration may be the metric that should be focused on to develop further strategies to protect against severe TBI for fall cases similar to those in this research. In addition, the HIC15 may not be suitable as a predictive metric for TBI and future development of protective devices for the prevention of head injury should take this into account.

Quantitative Image Analysis of Traumatic Brain Injury Induced Aspiration Pneumonia Treatment

Infection of the patient is one of the greatest risks inherent to surgical transplants. While great effort is taken to minimize this risk; variables outside of surgeon control can still result in transference of disease from donor to patient. Such conditions are common in lung transplants from donors having suffered traumatic brain injury (TBI). Autonomic nervous system damage from injury prior to transplant can result in involuntary intake of food into the lungs, developing into aspiration pneumonia. Remaining undetected until complications arise in the recipient. This study evaluated TBI model mice treated with simulated transplant conditions. The control groups included: aspiration pneumonia, aspiration treated with phosphate buffered saline (PBS), TBI without aspiration, TBI with aspiration and no treatment, TBI with PBS, TBI with aspiration treated with PBS. Drug treatment groups of TBI with aspiration pneumonia were dosed with either BB5, or a proprietary complement inhibitor.Mouse lung tissue was removed and fixed in 10% neutral buffered formalin (10% NBF) for 24 hours, processed into a paraffin block, cut via microtome and H&amp;E stained. Slides were then examined and whole slide digital images were created and evaluated using quantitative imaging software. The software utilized for calculating the percentage of inflammatory cellular infiltrates across the groups used Red‐Green‐Blue color algorithms to classify stained tissue slides. Initial analysis with Aperio Imagescope was unable to classify the color difference between similarly stained inflammatory cells and alveoli septa in the lungs. Indica Lab's HALO software was used for the second round of analysis. Both drug treatment groups were determined to have a biologically significant reduction in aspiration pneumonia compared to the control groups in both analysis systems. Indica Labs' HALO software was more specific in differentiating inflammatory cells in this difficult analysis.

Prospective Tracking and Analysis of Traumatic Brain Injury in Veterans and Military Personnel

ObjectiveTo describe the ongoing Clinical Tracking Form (CTF) study of the Defense and Veterans Brain Injury Center (DVBIC). DesignProspective longitudinal study. Data at baseline and postinjury are collected on participants through interview and questionnaire, review of medical records, and periodic follow-ups throughout their lifetime. SettingA regional DVBIC site located at a Veterans Affairs Medical Center. ParticipantsParticipants (N=211; age range, 18–75y) were enrolled between January 1, 2005, and December 31, 2012, at a regional DVBIC site. InterventionNot applicable. Main Outcome MeasuresInjury information, functioning, and psychological health. ResultsSixty percent of 211 participants were identified as having severe traumatic brain injuries (TBIs), 14% moderate TBIs, and 26% mild TBIs. Of these 211 participants, 79% sustained closed head injuries, 15% penetrating head injuries, and 6% were not reported. Comparing the severity of TBI in combat versus stateside situations, most of the mild injuries (71%) occurred in combat locations, while most of the severe injuries (62%) occurred in the United States. Among those injured in combat, blast-related TBIs (82%) greatly outnumbered non–blast-related TBIs, regardless of severity. ConclusionsThe CTF study serves as a significant resource of data to understand the effect and outcomes of TBI in the military population. The lifelong experience of military veterans across the full spectrum of TBI and recovery will be recorded through the CTF, and will translate into more informed clinical decisions and educational efforts to guide future research pathways.

Análise clínica e descritiva de traumatismos cranioencefálicos de um hospital em Uberaba-MG

Análise clínica e descritiva de traumatismos cranioencefálicos de um hospital em Uberaba-MG

Multivariate analysis of traumatic brain injury: development of an assessment score.

Important challenges for the diagnosis and monitoring of mild traumatic brain injury (mTBI) include the development of plasma biomarkers for assessing neurologic injury, monitoring pathogenesis, and predicting vulnerability for the development of untoward neurologic outcomes. While several biomarker proteins have shown promise in this regard, used individually, these candidates lack adequate sensitivity and/or specificity for making a definitive diagnosis or identifying those at risk of subsequent pathology. The objective for this study was to evaluate a panel of six recognized and novel biomarker candidates for the assessment of TBI in adult patients. The biomarkers studied were selected on the basis of their relative brain-specificities and potentials to reflect distinct features of TBI mechanisms including (1) neuronal damage assessed by neuron-specific enolase (NSE) and brain derived neurotrophic factor (BDNF); (2) oxidative stress assessed by peroxiredoxin 6 (PRDX6); (3) glial damage and gliosis assessed by glial fibrillary acidic protein and S100 calcium binding protein beta (S100b); (4) immune activation assessed by monocyte chemoattractant protein 1/chemokine (C–C motif) ligand 2 (MCP1/CCL2); and (5) disruption of the intercellular adhesion apparatus assessed by intercellular adhesion protein-5 (ICAM-5). The combined fold-changes in plasma levels of PRDX6, S100b, MCP1, NSE, and BDNF resulted in the formulation of a TBI assessment score that identified mTBI with a receiver operating characteristic (ROC) area under the curve of 0.97, when compared to healthy controls. This research demonstrates that a profile of biomarker responses can be used to formulate a diagnostic score that is sensitive for the detection of mTBI. Ideally, this multivariate assessment strategy will be refined with additional biomarkers that can effectively assess the spectrum of TBI and identify those at particular risk for developing neuropathologies as consequence of a mTBI event.

Are boys and girls that different? An analysis of traumatic brain injury in children

IntroductionThe Phillips Report on traumatic brain injury (TBI) in Ireland found that injury was more frequent in men and that gender differences were present in childhood. This study determined when...

Intersections of Disability Studies and Critical Trauma Studies: A Provocation

In this essay, we explore possible affinities between disability studies and trauma studies. We suggest that a fruitful engagement between these fields should start with the meanings of trauma and disability in their embodiment. We offer theoretical provocations alongside a comparative cultural analysis of traumatic brain injury and obstetric fistula. Ironically, while many disability studies scholars have worked to dislodge definitions of "abnormal" from the body, a conceptual focus on stigma still keeps the disabled body partially in view. Yet wounds, impairment, and pain are erased, and in many framings, the object of analysis is an individual being, whose now-disabled body is socially constructed, and whose agency is posited as being in struggle and resistance against the normative culture. We suggest that the body itself provides a link between disability studies and critical trauma studies, arguing both for the significance of representations as well a materialist understanding of breach, for a notion of the organic, fleshy body as it is damaged, sometimes profoundly, in its operations of life.Keywords: Disability studies; Trauma studies; Traumatic Brain Injury; Obstetric Fistula; Theory

Analysis of traumatic brain injury due to primary head contact during vehicle-to-pedestrian impact

We developed a 50th-percentile American male pedestrian model including a detailed brain, and the mechanical responses and kinematic biofidelity predicted by this model were validated against the available cadaveric test data. Vehicle-to-pedestrian impact simulations were then performed to investigate a potential mechanism for traumatic brain injury resulting from a lateral blunt impact to the head. Due to inertia of the brain mass, it was found that the average traction force produced in the cervical spinal cord exceeded 50 N in the impact involving a sport utility vehicle and 25 N in the impact involving a sedan, when the striking vehicle was travelling at 40 km/h. This inertial loading may play a key role in a brainstem, or upper-cervical-cord, lesion occurring before head strike. Results of this study suggest that close attention should be paid to pedestrian kinematics during free flight even before the head makes primary contact with the striking vehicle.

Proteomic analysis of traumatic brain injury: the search for biomarkers

Although there are a number of causes of traumatic brain injury (TBI), the armed conflict in Iraq and Afghanistan has brought this disorder to the attention of the global community. A biomarker that would enable army medics to rapidly diagnose the severity of TBI on the battle-field would be a huge asset. Unfortunately, the study of TBI has not historically attracted the proteomic research community’s interest as other disorders have, such as cancer. On the positive side, however, many of the analytical and technological challenges that were overcome in the development of biofluid proteomic methods are now being applied to the study of TBI. In this review, we discuss and highlight select examples of discovery-driven proteomic studies focused on finding effective biomarkers for TBI.

Mechanical Characterization of Brain Tissue in High-Rate Extension

Mechanical properties of brain tissue characterized in high-rate loading regime are indispensable for the analysis of traumatic brain injury (TBI). However, data on such properties are very limited. In this study, we measured transient response of brain tissue subjected to high-rate extension. A series of uniaxial extension tests at strain rates ranging from 0.9 to 25 s-1 and stress relaxation tests following a step-like displacement to different strain levels (15-50%) were conducted in cylindrical specimens obtained from fresh porcine brains. A strong rate sensitivity was found in the brain tissue, i.e., initial elastic modulus was 4.2 ± 1.6, 7.7 ± 4.0, and 18.6 ± 3.6 kPa (mean ± SD) for a strain rate of 0.9, 4.3, and 25 s-1, respectively. In addition, the relaxation function was successfully approximated to be strain-time separable, i.e., material response can be expressed as a product of time-dependent and strain-dependent components as:K(t) = G(t)σe(e), where G(t) is a reduced relaxation function, G(t) = 0.416e-t/0.0096+0.327e-t/0.0138+0.256e-t/1.508, and σe(e) is the peak stress following a step input of e. Results of the present study will improve biofidelity of computational models of a human head and provide useful information for the analysis of TBI under injurious environments with strain rates greater than 10 s-1.