Cumulative Effect of Concussion

Gronwall, Dorothy; Wrightson, Philip

doi:10.1016/s0140-6736(75)90288-3

Cited by 362 publications

(167 citation statements)

References 2 publications

Supporting

Mentioning

161

Contrasting

Order By: Relevance

“…28 Specifically, Gronwall and Wrightson found that individuals with a history of repeated mild TBI took longer to reach normal information-processing speeds after experiencing a mild TBI. 29 Repeated mild TBI is of particular importance for children and adults who participate in collision sports such as football, soccer, ice hockey, and boxing. 30 Recent studies among high school and college athletes show prolonged effects resulting from sports-related concussion, 5,6 with one recent study showing that high school players had more prolonged effects than collegiate athletes.…”

Section: Discussionmentioning

confidence: 99%

Multiple Episodes of Mild Traumatic Brain Injury Result in Impaired Cognitive Performance in Mice

Creeley¹,

Wozniak²,

Bayly³

et al. 2004

Acad Emergency Med

View full text Add to dashboard Cite

Objectives: Results from recent studies on animal models of concussion suggest that multiple, rather than single, episodes of mild traumatic brain injury result in impaired cognitive performance in mice. The objective of the present study was to administer multiple impacts to the heads of mice while directly measuring the force of the impacts to determine how these parameters are related to transient loss of consciousness, cognitive deficits, and potential neuropathologic effects. Methods: Seven-week-old male C57BL/6 mice were randomly assigned to experimental conditions involving three impacts (weight-drop method) to the head to induce mild traumatic brain injury or to sham control procedures. Some impacted (n ¼ 10) and sham control (n ¼ 10) mice were evaluated behaviorally and tested for spatial learning using the Morris water maze (MWM), whereas other impacted (n ¼ 10) and sham control (n ¼ 5) mice were used for histopathologic analysis. Results: The mean (6SD) force of impact was 19 (63.5) N. Impacted mice took longer to regain consciousness compared with sham control mice (p \ 0.0005). Behavioral test results showed that the groups did not differ on activity or sensorimotor tests or during cued trials in the MWM. Impacted mice exhibited impaired spatial learning performance during place trials in the MWM (p \ 0.05). Silver staining revealed a contra-coup type of injury involving ventral brain structures in contact with or in close proximity to the skull. Conclusions: This multiple-impact model, delivered within a specifiable force range, results in transient, reversible loss of consciousness, a contra-coup brain injury, and cognitive impairment. Key words: traumatic brain injury; concussion; memory; cognition; mice. ACADEMIC EMERGENCY MED-ICINE 2004; 11:809-819. It is not clear whether mild traumatic brain injury (TBI) causes demonstrable long-term cognitive impairment in humans. A number of earlier epidemiologic studies suggest that this may be the case, but the use of retrospective designs, lack of appropriate control groups, and an inability to correct for several confounding factors did not allow for a straightforward interpretation of the results. [1][2][3][4] More recently, a number of studies of athletes who have experienced a sports-related concussion suggest that symptomatology and cognitive impairment can last for one week 5 and, in some cases, up to three months. 6 Animal models have been used to study the behavioral and neuropathologic sequelae associated with TBI. [7][8][9][10] In three of these studies, in which slightly different murine models of mild TBI were used, the results suggested that mild single impacts did not produce discernible learning/memory deficits when behavioral testing was conducted more than three days after impact. [8][9][10] In contrast, multiple mild impacts have usually been found to produce significant effects on behavior, but the nature of these changes has been inconsistent across studies. For example, DeFord et al. 10 reported that multiple mild impacts ...

show abstract

Section: Discussionmentioning

confidence: 99%

Multiple Episodes of Mild Traumatic Brain Injury Result in Impaired Cognitive Performance in Mice

Creeley¹,

Wozniak²,

Bayly³

et al. 2004

Acad Emergency Med

View full text Add to dashboard Cite

show abstract

“…Do these lesions relate to neuropsychological function? What Gronwall and Wrightson (1975) demonstrated years ago suggested that concussion may not be as benign as Miller (1961) had implied, but may be very dependent on the cognitive demands placed on a patient. Routine cognitive tasks may be unaffected, whereas more complex functions affected.…”

Section: Pathophysiology Of Concussionmentioning

confidence: 99%

Neuropsychology and clinical neuroscience of persistent post-concussive syndrome

Bigler

2007

J Int Neuropsychol Soc

363

248

View full text Add to dashboard Cite

On the mild end of the acquired brain injury spectrum, the terms concussion and mild traumatic brain injury (mTBI) have been used interchangeably, where persistent post-concussive syndrome (PPCS) has been a label given when symptoms persist for more than three months post-concussion. Whereas a brief history of concussion research is overviewed, the focus of this review is on the current status of PPCS as a clinical entity from the perspective of recent advances in the biomechanical modeling of concussion in human and animal studies, particularly directed at a better understanding of the neuropathology associated with concussion. These studies implicate common regions of injury, including the upper brainstem, base of the frontal lobe, hypothalamic-pituitary axis, medial temporal lobe, fornix, and corpus callosum. Limitations of current neuropsychological techniques for the clinical assessment of memory and executive function are explored and recommendations for improved research designs offered, that may enhance the study of long-term neuropsychological sequelae of concussion. (JINS, 2008, 14, 1-22.)

show abstract

“…12,15,19,20 Given the serious short-and long-term effects following mild traumatic brain injury, the application of appropriate initial management practices is essential. [21][22][23][24][25][26] Numerous guidelines for the management of concussion have been released from specialty groups (including sports medicine, neurology, pediatrics, and family medicine) and from large medical associations. There is a collective agreement across all guidelines that the initial management should include removal from play, physical and cognitive rest, and graduated return to normal activities following medical clearance.…”

Section: Introductionmentioning

confidence: 99%

Canadian pediatric emergency physician knowledge of concussion diagnosis and initial management

Zemek

Eady

Farion

et al. 2015

CJEM

View full text Add to dashboard Cite

Introduction: The diagnosis of concussion is a critical step in the appropriate management of patients following minor head trauma. The authors hypothesized that wide practice variation exists among pediatric emergency medicine physicians in the application of physical and cognitive rest recommendations following an acute concussion. Methods: The authors developed a 35-item questionnaire incorporating case vignettes to examine pediatric emergency physician knowledge of concussion diagnosis, understanding of initial management using return-to-play/school/work guidelines, use of existing concussion protocols, and perceived barriers to protocol use. Using a modified Dillman technique, the authors distributed an online survey to members of Pediatric Emergency Research Canada, a national association of pediatric emergency physicians. Results: Of 176 potential participants, 115 (65%) responded to the questionnaire, 89% (95% confidence interval [CI]: 0.81, 0.93) of whom reported having diagnosed 20 or more concussions annually. Although 90% (95% CI: 0.83, 0.94) of respondents adequately diagnosed concussion, only 64% (95% CI: 0.54, 0.72) correctly applied graduated return-to-play guidelines. Cognitive rest recommendations were also frequently limited: 40% (95% CI: 0.31, 0.49) did not recommend school absence, 30% (95% CI: 0.22, 0.39) did not recommend schoolwork reduction, and 35% (95% CI: 0.27, 0.45) did not recommend limiting screen time. Eighty percent (95% CI: 0.72, 0.87) of respondents reported having used guidelines frequently or always to guide clinical decisions regarding concussion. Conclusion: Despite a proficiency in the diagnosis of concussion, pediatric emergency physicians exhibit wide variation in recommending the graduated return to play and cognitive rest following concussion.

show abstract

Cumulative Effect of Concussion

Cited by 362 publications

References 2 publications

Multiple Episodes of Mild Traumatic Brain Injury Result in Impaired Cognitive Performance in Mice

Multiple Episodes of Mild Traumatic Brain Injury Result in Impaired Cognitive Performance in Mice

Neuropsychology and clinical neuroscience of persistent post-concussive syndrome

Canadian pediatric emergency physician knowledge of concussion diagnosis and initial management

Contact Info

Product

Resources

About