Emotional response to sport concussion compared to ACL injury

Brain Inj Downloaded from informahealthcare.com by University of Toronto on 07/12/11 

For personal use only. 

Brain Injury, April 2010; 24(4): 589–597 

Emotional response to sport concussion compared to ACL injury 

LYNDA M. MAINWARING 1 , MICHAEL HUTCHISON 1 , SEAN M. BISSCHOP 2 , 

PAUL COMPER 2 , & DOUG W. RICHARDS 1 

1 University of Toronto, Faculty of Physical and Health Education, Toronto, ON, Canada and 

2 Toronto Rehabilitation Institute, Toronto, ON, Canada 

(Received 23 February 2009; revised 21 December 2009; accepted 10 January 2010) 

Abstract 

Primary objectives: To ascertain and compare the nature of emotional response of athletes to concussion and to anterior 

cruciate ligament (ACL) injury. 

Research design: Pre-injury, post-injury and longitudinal emotional functioning of athletes with concussion (n ¼ 16), 

athletes with ACL injuries (n ¼ 7) and uninjured athletes (n ¼ 28) were compared in a prospective repeated-measures 

design. 

Methods and procedures: Participants completed the short version of the Profile of Mood States (POMS). ANOVAs and trend 

analysis were used to examine between and within group differences across time on two sub-scales, Total Mood 

Disturbance and Depression. 

Main outcomes and results: Athletes with ACL injury reported higher levels of depression for a longer duration than athletes 

with concussion. Relative to un-injured controls, athletes with concussion reported significant changes in Total Mood 

Disturbance and Depression post-injury, whereas athletes with ACL injuries reported significant changes in Depression 

scores only. Different patterns of post-injury emotional disturbance for the injured groups were observed by trend analyses. 

Conclusions: Concussed athletes do not report as much emotional disturbance as athletes with ACL injuries. Differential 

patterns of emotional disturbance were detected between injured groups. The authors recommended that clinical protocols 

and educational programmes address emotional sequelae associated with sport concussion and ACL injury. 

Keywords: Sport concussion, emotional disturbance, profile of mood states, recovery, ACL injury 

Introduction 

Sports concussion research has typically focused on 

neurocognitive and not on emotional sequelae. 

Clinical evidence suggests a connection between 

cerebral concussion and changes in emotional state. 

Emotional symptoms such as depression and anxiety 

interfere with cognitive processes [1] and may rightly 

bear on short-term return-to-play decisions. Quite 

apart from that, emotional lability and depression, in 

particular, may have enduring and far reaching 

adverse psychological consequences for the athlete. 

Recent research and clinical anecdote suggest that 

the empirical investigation of emotional disturbance 

following concussion is warranted. 

In non-athletic mild brain-injured populations, 

emotional disturbances have been identified immediately 

after injury [2–4] and long after severe brain 

injury [5–8]. Depression is routinely reported after 

traumatic brain injury (TBI), regardless of injury 

severity [9, 10]. Jorge and Robinson [11] identified 

the range of frequencies for depressive disorders 

following TBI as 6% in mild TBI to 77% in more 

severe cases. Despite these findings and clinical 

evidence of an association between emotional 

sequelae and protracted recovery, empirical studies 

are sparse [12]. 

Recent prospective research of concussed athletes 

have revealed acute elevated depression, confusion, 

Correspondence: Dr Lynda Mainwaring, Faculty of Physical Education and Health, University of Toronto, 55 Harbord St. Toronto, ON M5S 2W6, Canada. 

Tel: (416) 946-5134. Fax: (416) 978-4384. E-mail: lynda.mainwaring@utoronto.ca 

ISSN 0269–9052 print/ISSN 1362–301X online ß 2010 Informa Healthcare Ltd. 

DOI: 10.3109/02699051003610508



590 L. Mainwaring et al. 

fatigue, anger, overall mood disturbance and 

reduced vigour following sports concussion 

[13, 14]. Functional magnetic resonance imaging 

(fMRI) studies have shown a reduction in cerebral 

activity in the dorsolateral prefrontal cortex and 

increased neural activation in the anterior cingulate 

and medial orbito frontal cortices of concussed 

athletes with depression [15]. Such findings are 

typically found in patients with major depressive 

disorder [16]. Depression increases the likelihood of 

anger, aggression, the risk of suicide and cognitive 

dysfunction following TBI [17–19]. Depression has 

also been identified as a possible long-term consequence 

of concussion in athletes by a large retrospective 

study. For example, football players with 

histories of previous concussion were found to be 

three times more likely diagnosed with depression 

after retirement [20]. 

The sport psychology literature has not examined 

long-term consequences of sport injury, but has 

clearly established that temporary emotional disturbances 

exist as a consequence of athletic injury. 

Athletes report increased tension, anger, depression, 

reduced vigour and overall emotional disturbance 

following musculoskeletal injuries [21–24]. It is not 

clear, however, if different patterns of emotional 

sequelae are associated with different types of injury 

and no research has examined whether different 

emotional responses are experience by athletes with 

musculoskeletal injury and athletes with cerebral 

concussion. 

The empirical literature on emotional reaction to 

injury in sport is fraught with methodological 

difficulties related to terminology and measurement. 

For example, the terms mood, emotion and affect 

are often used interchangeably when distinct meanings 

associated with each of these constructs are used 

in the theoretical literature. It is beyond the scope of 

this paper to examine these shortcomings. For the 

purpose of this paper, emotional disturbance refers 

to changes in the characteristic way a person 

interprets and expresses his/her emotions or feelings. 

The purpose of this prospective study was to 

examine and compare emotional disturbance and 

depression following sports concussion and musculoskeletal 

injury relative to un-injured controls. 

Because much of the research on emotional response 

to athletic injury has focused on anterior cruciate 

ligament (ACL) injuries and revealed that athletes 

experiences negative emotions following ACL injury 

[25–29], athletes with ACL injuries were recruited as 

an injury control group. Three hypotheses were 

examined: The first, with the aim of ruling out 

pre-morbid emotional dysfunction, stated that there 

would be no differences in baseline scores of 

emotional functioning between groups of injured 

athletes and a control group of un-injured athletes; 

the second stated that emotional disturbance, as 

measured by changes in Total Mood Disturbance 

and Depression Scales of the Profile of Mood States 

(POMS) [30], would be evident post-injury for both 

injured groups; and the third examined whether 

emotional disturbance of athletes with cerebral 

concussion varied from that of athletes with ACL 

injuries. Such research aims to enhance understanding 

of the nature of emotional sequelae of sport 

concussion and shed light on whether those sequelae 

are a result of athletic injury experience in general or 

concussion specifically. 

Method 

Participants 

Three groups of University of Toronto undergraduate 

student-athletes participated: (1) Concussed 

varsity athletes (CONC: M ¼ 12, F ¼ 4), (2) athletes 

with confirmed anterior cruciate ligament injuries 

(ACL: M ¼ 1, F ¼ 6) and (3) Un-injured athletes 

(CTL: M ¼ 8, F ¼ 20). Athletes from nine varsity 

sports teams (basketball, field hockey, football, 

hockey, lacrosse, mountain biking, rugby, soccer 

and volleyball) completed mandatory baseline testing. 

If injured, and they met the inclusion/exclusion 

criteria and they volunteered for the study the 

athletes were assigned as appropriate to either the 

concussed or ACL group. The inclusion criteria for 

the ACL group specified that the injury had to meet 

diagnostic criteria for either suspect or confirmed 

ACL injury by a physician. All athletes approached 

with ACL injuries agreed to volunteer in the study; 

however, in some cases (n ¼ 2) the injury was not 

detected or reported within the time-frame necessary 

for participation in the research and so the athletes 

were not tested. The non-injured athletes were 

volunteers from a pool of students who were 

involved in sports other than collision sports and 

completed the baseline and serial test batteries. 

Written informed consent was completed at the first 

testing time and included a request for permission to 

contact the athlete in the event s/he sustained a 

concussion or ACL injury at any game or practice 

throughout the athlete’s inter-university sport career. 

Consenting athletes who subsequently sustained 

cerebral concussion or ACL-injury were contacted 

by a research coordinator, completed a second 

informed consent and were scheduled for a series 

of repeated assessments to monitor recovery if they 

wished to volunteer for the research. 

Design and procedure 

The research protocol was approved by the 

Ethics Review Office of the University of Toronto.



The quasi-experimental design was a prospective 

mixed cohort design with repeated measures collected 

by two independent and mutually-blinded 

teams: (1) McIntosh Sports Medicine Clinic physicians 

and therapists who identified and cared for 

injured athletes and (2) Toronto Rehabilitation 

Institute and University of Toronto psychologists 

and psychometrists. The clinicians were blinded to 

neuropsychological test results so that return-to-play 

decisions were not influenced. Similarly, the 

researchers were not provided with the medical 

record data to provide objectivity in test administration 

and data collection. The sport medicine personnel 

were only informed of the results of the 

neuropsychological testing when a concussed athlete’s 

neuropsychological tests showed abnormal 

scores (determined by a neuropsychologist) and the 

athlete’s history of concussion suggested the athlete 

may be at risk if returned to play prematurely. 

Baseline emotional states for all student-athletes 

participating in contact or collision sports were 

measured during a 60-minute pre-season medical 

and neuropsychological assessment. All athletes 

were assessed during the competitive season, 

August through March. Participants in the noninjured 

control group completed serial tests during a 

similar assessment schedule from January to March. 

Concussions were identified by a physician, 

Certified Athletic Therapist or student therapist 

present at the sideline during either a practice or 

game, who applied specific assessment/diagnosis 

guidelines determined by the sports medicine director. 

Concussion was diagnosed based on the following 

criteria developed by the research team: 

(1) Observed or reported acceleration/deceleration 

of the head; (2) Any observable alteration in mental 

status; (3) Observable signs such as confusion, 

vacant stare, poor coordination, difficulty concentrating, 

poor balance; and/or (4) Any self-reported 

symptoms such as headache, loss of consciousness, 

nausea, balance problems or difficulty reading 

or concentrating. After emergency was ruled out, 

a brief sideline mental status exam was administered 

to document post-concussive behaviour and 

symptoms. Positive neurologic signs or unusual 

cognitive performance led to removal from competition 

and scheduling of serial post-injury 

assessments. 

When possible, athletes were scheduled for 

post-injury assessments on days 1 (date of injury), 

4, 8, 15, 22 and 29. Team travel and student-athlete 

schedules often delayed the first post-injury time. As 

a consequence, the two groups of injured athletes 

completed their first post-injury assessments at 

significantly different time points during recovery 

[F(1, 20) ¼ 39.0, p < 0.05, 2 p ¼ 0.66]. Athletes in the 

concussed group completed Time 2 assessments an 

Emotional response to sport concussion 591 

average of 3.6 days (SD ¼ 2.2, Median ¼ 3 days, 

Range 1–9) post-injury. The athletes with ACL 

injuries were seen an average of 11 days (SD ¼ 3.3, 

Median ¼ 11 days, Range 6–16) post-injury, largely 

due to injury-related mobility issues and delayed 

referral times. Because of the differences in 

post-injury testing days between groups, the data 

are presented by reference to the median days 

post-injury as well as by assessment time for each 

group. A matched cohort control group drawn from 

the contact/collision sports was deliberately avoided. 

Exposing a sub-set of such uninjured cohort athletes 

to serial assessment would have jeopardized any 

subsequent clinical neuropsychological assessment 

and forced the exclusion of these athletes from 

participation in the research should they have 

sustained concussion [31]. 

Measures 

Demographics. All participants completed a demographic 

questionnaire that assessed background 

information including age, sex, height, weight and 

previous concussion history (up to a maximum of 

five previous concussions). 

Emotional disturbance. Pre- and post-injury emotional 

responses were assessed with a short version of 

the Profile of Mood States (POMS) [30], which was 

chosen for its brief administration time and its use in 

sport. This version of the POMS consisted of 40 

adjectives (e.g. restless, discouraged) organized into 

seven sub-scales (1) Tension, (2) Depression, (3) 

Anger, (4) Vigour, (5) Fatigue, (6) Confusion and 

(7) Self-esteem. Participants rated each adjective on 

a 5-point Likert scale from 0 (not at all) to 4 

(extremely) according to how they feel ‘right now’. 

Total Mood Disturbance was calculated by subtracting 

positive mood scores (vigour and 

self-esteem) from the sum of negative mood scores 

then adding a constant of 100 [30]. These 

sub-scales have been previously assessed for reliability 

and validity, demonstrating Cronbach’s alphas 

ranging from 0.664–0.954 with a mean of 

0.798 [30]. 

Statistical analysis 

POMS sub-scale reliabilities were examined with 

Cronbach’s alpha coefficients [32]. Demographics 

and physical characteristics were compared across 

groups using univariate analysis of variance 

(ANOVA) and Bonferroni-adjusted pairwise comparisons. 

Non-parametric Kruskal-Wallis tests were 

used for univariate ANOVAs when the data violated 

the parametric assumption of homogeneity of




variances, as identified by Levene’s test for 

homogeneity. 

A one-way ANOVA for group and planned 

pairwise group comparisons at Time 1 were conducted 

to rule out pre-morbid dysfunction and test 

Hypothesis 1. To assess emotional dysfunction 

following injury, hypothesis 2, change scores for 

Total Mood and Depression between baseline and 

the first post-injury assessment were examined 

across the three groups with a one-way ANOVA 

with subsequent planned pairwise comparisons. 

Bonferroni-adjustments were used to control for 

Type I error inflation typically associated with 

multiple comparisons. 

To identify group differences in longitudinal 

emotional profiles (Hypothesis 3) a 3 (group) 4 

(time) repeated measures ANOVA (RM-ANOVA) 

was performed for each POMS sub-scale. Significant 

Group Time interactions were examined with 

polynomial trend analysis. Estimates of effect size 

are reported as partial eta-squared ( 2 p ), which can be 

thought of as the proportion of variance in the 

dependent variable that is explained by differences 

among the groups regardless of group size. For the 

RM-ANOVAs Mauchly’s test of sphericity was used 

to identify violations in the assumption of sphericity 

(homogeneity of variances for repeated factors). 

Where violations in sphericity were identified, 

Greenhouse-Geisser corrections were made to the 

F-statistic. 

Results 

Descriptive statistics 

Reliabilities for each sub-scale of the POMS 

short-form were calculated with Cronbach alpha 

coefficients [32]. All alphas exceeded the recommended 

0.70 [33] except for Self-Esteem. 

The average age across the groups was 21.2 years 

(SD ¼ 2.94; Range 17.5–37.0) with no differences 

between groups [F(2, 48) ¼ 0.80, p ¼ 0.46, 

2 

p ¼ 0.03]. There were significant differences in 

2 height [F(2, 48) ¼ 6.75, p < 0.01, p ¼ 0.22] and 

2 weight [F(2, 48) ¼ 9.04, p < 0.01, p ¼ 0.27] among 

the groups, with the Concussed group being 

significantly taller (4.2; p ¼ 0.02, 95% CI ¼ 1.4, 

7.1) and heavier (32 lbs; p < 0.01, 95% CI ¼ 13.0, 

50.7) than the control group. The concussed athletes 

were an average of 28 pounds heavier than the 

athletes with ACL injuries. Concussed athletes were 

removed from play for an average of 25 days and 

returned to play 10 days after the fourth assessment 

time, which was day 14 post-injury. Athletes 

with ACL injuries failed to report a single prior 

concussion, contributing to a significant Levene’s 

test (homogeneity of variance) [Levene’s statistic 

(2, 48) ¼ 6.75, p < 0.01]. The ensuing nonparametric 

Kruskal-Wallis test was significant 

[ 2 2 (2, 48) ¼ 10.9, p < 0.01] and indicated differences 

in the average number of prior concussions reported 

by each group. The concussed group had the highest 

number of mean previous concussions (1.4, 

SD ¼ 1.3) followed by the uninjured group (1.00, 

SD ¼ 1.00) and the athletes with ACL injuries (0). 

Baseline assessments. A one-way ANOVA revealed 

that injured groups did not differ from uninjured 

healthy controls in baseline assessment on any of the 

sub-scales of the POMS and, thus, Hypothesis 1 was 

supported. Table I shows POMS means and standard 

deviations for each group at each assessment 

time for the main outcome measures, Total Mood 

and Depression. Homogeneity of variance was 

demonstrated for each sub-scale. 

First post-injury assessment. A one-way ANOVA by 

group on change scores between pre-injury and the 

first post-injury assessment revealed significant 

differences for Total Mood Disturbance 

[F(2, 48) ¼ 3.369, p < 0.04] and Depression 

[F(2, 48) ¼ 6.866, p < 0.002]. Tukey HSD tests 

determined that the Concussed group differed 

from the uninjured control (p ¼ 0.03) for Total 

Mood Disturbance and also for Depression 

(p ¼ 0.03). The ACL group was significantly different 

from the uninjured control group on Depression 

(p ¼ 0.005). Although concussed athletes endorsed 

almost three times more Depression at the first 

post-injury assessment (Time 2) than they did prior 

to injury at baseline, athletes with ACL injuries 

Table I. Profile of mood state depression and total mood 

disturbance scores for three groups (CON, ACL and CTL) at 

each of four test sessions. 

CONC (n ¼ 16) ACL (n ¼ 7) CTL (n ¼ 28) 

Session M SD M SD M SD 

Depression 

1 1.31 2.55 0.71 0.95 1.54 3.13 

2 3.75 4.55 5.00 4.40 1.54 2.41 

3 1.69 2.63 2.71 2.56 0.86 1.69 

4 0.63 1.78 0.86 1.22 1.32 2.23 

Total* 

1 97.81 18.89 105.43 15.55 102.21 15.19 

2 116.69 22.39 114.71 14.12 106.36 13.38 

3 108.44 17.17 110.86 18.18 100.89 14.52 

4 100.69 12.29 104.57 12.51 105.61 14.04 

*Total ¼ (tension þ depression þ anger þ fatigue þ confusion) þ 

(vigour þ esteem) þ 100. 

1 ¼ baseline test; 2 ¼ first post-injury assessment (4 days); 3 ¼ 7 

days post-injury; 4 ¼ 14 days post-injury.



reported over seven times more Depression after 

injury than at baseline (see Table I). 

Longitudinal emotional functioning 

Total mood disturbance. A 3 (group) 4 (time) 

RM-ANOVA detected a significant interaction for 

Total Mood Disturbance scores [F(6, 144) ¼ 2.99, 

2 p < 0.01, p ¼ 0.11] with a significant simple main 

effect for the concussed group [F(3, 45) ¼ 6.20, 

2 

p < 0.01, ¼ 0.29]. Polynomial trend analyses 

revealed a significant quadratic trend for the 

concussed group [F(1, 15) ¼ 11.72, p < 0.01, 

2 

p ¼ 0.44] (see Figure 1). Again, homogeneity of 

variance was present for all assessment times except 

Time 2, in which concussed athletes showed a 

strikingly large variability relative to athletes with 

ACL injury. 

Depression. A3 4 RM-ANOVA detected a significant 

Group Time interaction [F(6, 144) ¼ 4.53, 

2 p < 0.01, p ¼ 0.16] for Depression scores and a 

significant simple main effect for time for the 

concussed athletes [F(3, 45) ¼ 4.90, p < 0.01, 

2 

p ¼ 0.25] (see Figure 2). Polynomial trend analyses 

revealed a significant quadratic trend [F(1,48) ¼ 

2 6.98, p < 0.02, p ¼ 0.32] and near significant cubic 

trend for depression (p ¼ 0.056). For the athletes 

with ACL injuries there was also a significant simple 

main effect of time for depression [F(3, 18) ¼ 6.46, 

2 p < 0.01, p ¼ 0.52] which followed a quadratic 

2 trend [F(1, 6) ¼ 11.3, p < 0.02, p ¼ 0.65]. 


Homogeneity of variance was noted at all times 

except Time 2, when the injured athlete groups 

showed marked within-group variability relative to 

uninjured controls. 

No simple main effects were significant for the 

control group (CTL) for any sub-scale. 

Discussion 

Consistent with other research, results of this study 

suggest response to athletic injury is not a result of 

pre-morbid emotional dysfunction [34, 35]. This 

study supported the first hypothesis and ruled out 

pre-injury emotional disturbances in athletes with 

concussion and those with ACL injuries. 

The second hypothesis that emotional functioning 

would deteriorate post-injury for both injured groups 

was partially accepted in that both groups reported 

significant increases in depression scores post-injury 

compared with the un-injured group. Concussed 

athletes reported significant changes in overall emotional 

disturbance post-injury compared with the 

un-injured athletes, but not when compared to the 

athletes with ACL injuries. These findings support 

the suspected causal link between athletic injury and 

subsequent emotional distress [22, 25, 29, 36–40], 

but indicate that there are different patterns of 

emotional disturbance associated with different 

injuries. Athletes with ACL injuries reported over 

seven times more depression 11 days post-injury 

than at baseline. In contrast, 4 days post-injury 

Figure 1. Profile of POMS total mood disturbance scores for each group over time—using group median post-injury testing dates.




Figure 2. Profile of POMS depression ratings for each group over time—using group median post-injury testing dates. 

concussed athletes showed elevated depression 

scores three times greater than scores at baseline, 

but the elevations resolved 1 week after injury 

Statistical differences in patterns of recovery 

between injured groups and the un-injured controls 

(Hypothesis 3) were not supported by analysis of 

variance. Detectable differences between groups 

may have been concealed by the variability in the 

data and small sample sizes. In order to detect 

statistically significant between-group post-injury 

differences in emotions, if they are to be found, 

very large samples or more sensitive measures are 

needed. Low incidence and reporting of ACL injury 

and incomplete post-injury serial tests were limiting 

factors to increased sample sizes in this study. It is 

difficult to recruit athletes with ACL injuries for 

serial neuropsychological and emotional testing 

because of the nature of the injury and the physical 

treatment required. Also, there is little incentive for 

these athletes to devote hours of their time to 

repeated and seemingly irrelevant neuropsychological 

testing. Systematic patterns of disturbance in 

total mood disturbance and depression, however, 

were revealed in the two injured groups by polynomial 

trend analysis. No systematic differences in 

patterns of response over time were observed in the 

uninjured control group. Polynomial analyses 

showed more prolonged total disturbance and 

depression in the ACL group, whereas the concussed 

group displayed acute brief (1-week) elevated total 

disturbance and depression scores post-injury. The 

more prolonged and intense overall disturbance and 

depression in the ACL group may have been 

due to the injury severity, mobility limitations 

and greater rehabilitation involvement (e.g. MRI, 

surgery etc.). 

Other research [13] found depression scores for 

athletes with minor musculoskeletal injuries (ankle, 

wrist and shoulder strains and sprains) resolved over 

2-weeks post-injury, whereas elevated depression 

scores for concussed athletes returned to baseline in 

just over 1-week post-injury. Those findings, along 

with the results from this study, suggest that the 

nature and quality of emotional disturbance and 

perhaps the causal mechanism for concussion is 

different from that of musculoskeletal injuries. 

In this study changes in Total Mood Disturbance 

was also shown post-injury for the concussed 

athletes but not for the athletes with ACL injury. 

Prior research has demonstrated significant, albeit 

temporary, overall emotional disturbance following 

ACL injury [25, 27, 28]. The non-significant 

findings for the ACL group were probably a result 

of the small sample and variability within the sample 

and the inability to test the athletes 4 days 

post-injury. Although these findings are consistent 

with findings that TMD scores were not elevated in 

athletes with minor musculoskeletal injuries [13], 

they are inconsistent with the graphic representation 

(Figure 1), which illustrates post-ACL-injury elevation 

in TMD that returns to baseline 23 days 

post-injury, later than that of the concussed athletes. 

It is recommended that future studies take a closer 

look at post-injury differences in overall emotional



disturbance of athletes with concussion and those 

with musculoskeletal injuries. 

Overall emotional disturbance and depression 

seen in the first week post-concussion in the study 

mirrors the neurocognitive changes identified in 

many other concussion studies [41–48]. These 

transient changes in cognitive and emotional functioning 

seem to reflect athletes’ feelings of being ‘off’ 

or in a ‘fog’ [49] and it is speculated that they 

resonate with the transient neurochemical cascade 

[50–52] and physiologic disturbances [15] associated 

with brain trauma. Silver et al. [53] suggested 

that early post-traumatic depression was more likely 

related to a ‘host-injury interaction’ (p. 657) than 

later post-traumatic depression. 

Some authors have argued that emotional disturbance 

following injury is related to removal from 

competition rather than the injury itself [36]. 

Therefore, return-to-play dates were examined. 

Emotional changes abated prior to the athlete’s 

return to play, which was on average 25 days 

post-injury for the concussed group: Total Mood 

Disturbance scores returned to baseline levels 14 

days post-concussion and depression scores returned 

to baseline by the 7th day post-concussion. This 

finding suggests that removal from play is not the 

underlying factor that triggers depression or emotional 

disturbance in concussed athletes. 

The elevated overall emotional disturbance and 

depression scores post-concussion could also represent 

withdrawal from the endogenous opiates associated 

with feelings of well-being. The daily routines 

of athletes involve intense training, and it is possible 

that the short abrupt disruption in training associated 

with concussion disturbs neurochemistry. 

There is evidence that aerobic exercise increases 

endogenous opiates and feelings of well-being 

[54–57]. Athletes who are unable to train because 

of injury may experience an absence of such 

neurochemical boosts as emotional disturbance in 

association with the neurochemical cascade identified 

with cerebral concussion [50–52]. These ideas 

need to be examined in future research. 

Physical differences were seen between groups. 

The concussed group was physically heavier than the 

ACL group and taller and heavier than the uninjured 

control group. These physical differences were likely 

the result of a disproportionate number of females in 

the uninjured comparison group and the ACL 

group. In addition, the athletes with ACL injuries 

did not report any history of concussion, whereas, 

consistent with previous research [58–60], the 

concussed group reported a significantly different 

number (1.4) of previous concussions. There were 

no sex differences in emotional response to injury, 

but this could have been an artifact of insufficient 

power to detect differences. Ideally, groups would be 


matched on sex and other variables such as time 

intervals between testing sessions for all injury 

sub-groups. The authors recognize these as limitations 

to this study. 

In summary, over a 3-week period of assessment, 

both concussed and ACL-injured groups had emotional 

disturbance that declined as athletes recovered. 

Depression was more prolonged and intense 

for the athletes with ACL injuries, whereas concussed 

athletes reported elevated depression as well 

as overall emotional disturbance that resolved within 

1-week post-injury. 

Assessing emotional response to concussion has 

many methodological challenges, such as inconsistencies 

in injury reporting, the logistics of injury 

reporting mechanisms, sensitivity to the varied 

interests of coaches, athletes and medical personnel 

and the appropriateness of sensitive and brief measures. 

Well-articulated protocols for injury reporting, 

sound communication patterns and computerized 

measures of emotion [61] are recommended for 

future studies. 

These findings need to be replicated and the 

methods refined to make any definitive statements 

about the nuanced emotional differences after concussion 

and ACL injury or musculoskeletal injury in 

general. The variability in individual response to 

injury in both injured groups reinforces the assertion 

that individuals need to be treated relative to their 

own pre-injury and post-injury performance on any 

assessment [41, 43]. It also points to the importance 

of interpreting an individual’s data in terms of 

clinical significance and not merely statistical 

significance. 

In conclusion, it is believed that it is important to 

assess and study emotional functioning following 

concussion and to compare it to the response 

associated with musculoskeletal injury in order to 

discern which responses are associated with brain 

injury and which are a result of the psychosocial– 

behavioural consequences of the injury experience 

overall. Assessment of post-injury emotional functioning 

could help to inform return-to-play decisions 

so that athletes do not return-to-play with emotional 

disturbance, which might create a risk for further 

injuries. Often, athletes will not report emotional 

disturbance because they do not realize that such 

symptoms may be related to injury and because 

attitudes that reflect a play despite injury mentality 

associated with the culture of risk in sport [62] often 

influence under-reporting and denial of symptoms 

and injuries. In addition, monitoring post-traumatic 

emotional disturbances, in particular depression, in 

both concussed athletes and athletes with ACL 

injuries can potentially prevent emotional deterioration 

and facilitate early intervention.




It is recommended that future research on concussion 

in sport expands beyond the typical neurocognitive 

test battery to include the following: (1) An 

examination of short- and long-term emotional 

reactions post-injury, (2) Risk factors for depressive 

reaction following concussion, (3) Enhanced and 

automated measures of emotion, which include a 

broader range of emotions and more sensitive and 

specific tests, and (4) Examination of injured 

sub-group comparisons (minor musculoskeletal injuries, 

for example). Finally, it is recommended that 

concussion management protocols include 

post-injury emotional testing and monitoring in the 

interest of early comprehensive intervention and 

successful outcome; and that educational programmes 

acknowledge and emphasize emotional 

symptoms as sequelae of concussion. Emotional 

symptoms post-concussion need to be assessed 

clinically and empirically [63]. 

Declaration of interest: The authors report 

no conflicts of interest. The authors alone are 

responsible for the content and writing of the paper. 

References 

1. Bechara A, Damasio H, Damasio AR, Lee GP. Different 

contributions of the human amygdala and ventromedial 

prefrontal cortex to decision-making. The Journal of 

Neuroscience 1999;19:5473–5481. 

2. Paniak C, Reynolds S, Toller-Lobe G, Melnyk A, Nagy J, 

Schmidt D. A longitudinal study of the relationship between 

financial compensation and symptoms after treated mild 

traumatic brain injury. Journal of Clinical and Experimental 

Neuropsychology 2002;24:187–193. 

3. Dikmen S, McLean A, Temkin N. Neuropsychological and 

psychosocial consequences of minor head injury. Journal of 

Neurology, Neurosurgery and Psychiatry 1986;49: 

1227–1232. 

4. Levin HS, Mattis S, Ruff RM, Eisenberg HM, Marshall LF, 

Tabaddor K, et al. Neurobehavioral outcome following 

minor head injury: A three-center study. Journal of 

Neurosurgy 1987;66:234–243. 

5. Malia K, Powell G, Torode S. Personality and psychosocial 

function after brain injury. Brain Injury 1995;9:697–712. 

6. Bornstein RA, Miller HB, van Schoor JT. 

Neuropsychological deficit and emotional disturbance in 

head-injured patients. Journal of Neurosurgery 1989;70: 

509–513. 

7. Gasquoine PG. Postconcussion symptoms. Neuropsychology 

Review 1997;7:77–85. 

8. Brooks DN, McKinlay W. Personality and behavioural 

change after severe blunt head injury—a relative’s view. 

Journal of Neurology, Neurosurgery and Psychiatry 1983;46: 

336–344. 

9. Kreutzer JS, Seel RT, Gourley E. The prevalence and 

symptom rates of depression after traumatic brain injury: A 

comprehensive examination. Brain Injury 2001;15:563–576. 

10. Lyketsos CG, Lopez O, Jones B, Fitzpatrick AL, Breitner J, 

DeKosky S. Prevalence of neuropsychiatric symptoms in 

dementia and mild cognitive imipairment: Results from the 

cardiovascular health study. JAMA 2002;288:1475–1483. 

11. Jorge R, Robinson R. Mood disorders following traumatic 

brain injury. NeuroRehabiliation 2002;17:11–324. 

12. Johnston KM, McCrory P, Mohtadi NG, Meeuwisse W. 

Evidence-based review of sport-related concussion: Clinical 

science. Clinical Journal of Sport Medicine 2001;11: 

150–159. 

13. Hutchison M, Mainwaring L, Comper P, Richards DW, 

Bisschop S. Differential emotional responses of varsity 

athletes to concussion and musculoskeletal injuries. Clinical 

Journal of Sport Medicine 2009;19:13–19. 

14. Mainwaring LM, Bisschop SM, Green R, Antoniazzi M, 

Comper P, Kristman V, et al. Emotional reaction of varsity 

athletes to sport-related concussion. Journal of Sport and 

Exercise Psychology 2004;26:119–135. 

15. Chen J-K, Johnston KM, Petrides M. Neural substrates of 

symptoms of depression following concussion in male 

athletes with persisting postconcussion symptoms. Archives 

of General Psychiatry 2008;65:81–89. 

16. Liotti M, Mayberg HS, Brannan SK, McGinnis S, Jerabek P, 

Fox PT. Differential limbic-cortical correlates of sadness and 

anxiety in healthy subjects: Implications for affective disorders. 

Biological Psychiatry 2000;48:30–42. 

17. Fann JR, Katon WJ, Uomoto JM, Esselman PC. Psychiatric 

disorders and functional disability in outpatients with traumatic 

brain injuries. American Journal of Psychiatry 

1995;152:1493–1499. 

18. Hibbard MR, Uysal S, Kepler K, Bogdany J, Silver J. Axis I 

psychopathology in inidividuals with traumatic brain injury. 

Journal of Head Trauma Rehabilitation 1998;13:24–39. 

19. Rapoport MJ, McCullagh S, Shammi P, Feinstein A. 

Cognitive impairment associated with major depression 

following mild and moderate traumatic brain injury. Journal 

of Neuropsychiatry and Clinical Neuroscience 2005;17: 

61–65. 

20. Guskiewicz KM, Marshall SW, Bailes J, McCrea M, 

Harding HP, Matthews A, et al. Recurrent concussion and 

risk of depression in retired professional football players. 

Medicine and Science in Sports and Exercise 2007;39: 

903–909. 

21. Leddy MH, Lamber MJ, Ogles BM. Psychological 

consequences of athletic injury among high-level competitors. 

Research Quarterly for Exercise and Sport 1994;65: 

347–354. 

22. Smith AM, Stuart MJ, Wiese-Bjornstal DM, Milliner EK, 

O’Fallon WM, Crowson CS. Competitive athletes: Pre-injury 

and postinjury mood state and self-esteem. Mayo Clinic 

Proceedings 1993;68:939–947. 

23. Roh J, Newcomer RR, Perna FM, Etzel EF. Depressive 

mood states among college athletes: Pre- and post-injury. 

Journal of Applied Sport Psychology 1998;10(Suppl):S54. 

24. Miller WN. Athletic injury: Mood disturbances and hardiness 

of intercollegiate athletes. Journal of Applied Sport 

Psychology 1998;10(Suppl):S127–S128. 

25. Brewer BW, Van Raalte JL, Cornelius AE, Petitpas AJ, 

Sklar JH, Pohlman MH. Psychological factors, rehabilitation 

adherence and rehabilitation outcome after anterior cruciate 

ligament reconstruction. Rehabilitation Psychology 2000;45: 

20–37. 

26. Brewer BW, Linder DE, Phelps CM. Situational correlates of 

emotional adjustment to athletic injury. Clinical Journal of 

Sport Medicine 1995;5:241–245. 

27. Daly JM, Brewer BW, Van Raalte JL, Petitpas AJ, Sklar JH. 

Cognitive appraisal, emotional adjustment, and adherence to 

rehabilitation following knee surgery. Journal of Sport 

Rehabilitation 1995;4:23–30. 

28. Mainwaring LM. Restoration of self: A model for the 

psychological response of athletes to severe knee injuries. 

Canadian Journal of Rehabilitation 1999;12:145–156.



29. Morrey MA, Stuart MJ, Smith AM, Wiese-Bjornstal DM. A 

longitudinal examination of athletes’ emotional and cognitive 

responses to anterior cruciate ligament injury. Clinical 

Journal of Sport Medicine 1999;9:63–69. 

30. Grove J, Prapavessis H. Preliminary evidence for the reliability 

and validity of an abbreviated Profile of Mood States. 

International Journal of Sport Psychology 1992;23:93–109. 

31. Hinton-Bayre AD, Geffen GM, Geffen LB, McFarland KA, 

Friis P. Concussion in contact sports: Reliable change indices 

of impairment and recovery. Journal of Clinical and 

Experimental Neuropsychology 1999;21:70–86. 

32. Cronbach LJ, Meehl PE. Construct validity in psychological 

tests. Psychological Bulletin 1955;52:281–302. 

33. Nunnely J. Psychometric theory. 2nd ed. New York: 

McGraw Hill; 1978. 

34. Leddy MH, Lambert MJ, Ogles BM. Psychological consequences 

of athletic injury among high-level competitors. 

Research Quarterly for Exercise and Sport 1994;65:347–354. 

35. Smith AM, Stuart MJ, Wiese-Bjornstal DM, Milliner EK, 

O’Fallon WM, Crowson CS. Competitive athletes: Pre-injury 

and postinjury mood state and self-esteem. Mayo Clinic 

Proceedings 1993;68:939–947. 

36. Chan CS, Grossman HY. Psychological effects of running 

loss on consistent runners. Perceptual and Motor Skills 

1988;66:875–883. 

37. Chute N. Psychological responses and adjustments to sport 

injuries by varsity athletes. Master’s Thesis. Kingston, 

Canada: Queen’s University; 1997. 

38. McDonald SA, Hardy DJ. Affective response patterns of the 

injured athlete: An exploratory analysis. The Sport 

Psychologist 1990;4:261–274. 

39. Smith AM, Scott SG, O’Fallon WM, Young ML. Emotional 

responses of athletes to injury. Mayo Clinic Proceedings 

1990;65:38–50. 

40. Pearson L, Jones G. Emotional effects of sports injuries: 

Implications for physiotherapists. Physiotherapy 1992;78: 

762–770. 

41. Echemendia RJ, Putukian M, Mackin RS, Julian L, Shoss N. 

Neuropsychological test performance prior to and following 

sports-related mild traumatic brain injury. Clinical Journal of 

Sport Medicine 2001;11:23–31. 

42. Lovell MR, Collins MW, Iverson GL, Field M, Maroon JC, 

Cantu R, et al. Recovery from mild concussion in high school 

athletes. Journal of Neurosurgery 2003;98:296–301. 

43. Lovell MR, Collins MW, Iverson GL, Johnston KM, 

Bradley JP. Grade 1 or ‘ding’ concussions in high school 

athletes. American Journal of Sports Medicine 2004;32: 

47–54. 

44. Macciocchi SN, Barth JT, Alves W, Rimel RW, Jane JA. 

Neuropsychological functioning and recovery after mild head 

injury in collegiate athletes. Neurosurgery 1996;39:510–514. 

45. McCrea M, Guskiewicz KM, Marshall SW, Barr W, 

Randolph C, Cantu RC, et al. Acute effects and recovery 

time following concussion in collegiate football players: The 

NCAA Concussion Study. JAMA 2003;290:2556–2563. 

46. McCrea M, Kelly JP, Randolph C, Cisler R, Berger L. 

Immediate neurocognitive effects of concussion. 

Neurosurgery 2002;50:1032–1040, discussion 1040–1042. 

47. Pellman EJ, Lovell MR, Viano DC, Casson IR, Tucker AM. 

Concussion in professional football: Neuropsychological 


testing—part 6. Neurosurgery 2004;55:1290–1303, discussion 

1303–1305. 

48. Bleiberg J, Cernich AN, Cameron K, Sun W, Peck K, 

Ecklund PJ, et al. Duration of cognitive impairment after 

sports concussion. Neurosurgery 2004;54:1073–1078, discussion 

1078–1080. 

49. Iverson GL, Gaetz M, Lovell MR, Collins MW. Relation 

between subjective fogginess and neuropsychological testing 

following concussion. Journal of the International 

Neuropsychological Society 2004;10:904–906. 

50. Giza CC, Hovda DA. The neurometabolic cascade of 

concussion. Journal of Athletic Training 2001;36:228–235. 

51. Hovda DA, Becker DP, Katayama Y. Secondary injury and 

acidosis. Journal of Neurotrauma 1992;9(Suppl 1):S47–S60. 

52. Hovda DA, Prins M, Becker DP, Lee S, Bergsneider M, 

Martin NA. Neurobiology of concussion. In: Bailes JE, Lovell 

MR, Maroon JC, editors. Sports related concussion. St. 

Louis: Quality Medical Publishing; 1999. pp 12–51. 

53. Silver J, McAllister T, Arciniegas D. Depression and cognitive 

complaints following mild traumatic brain injury. The 

American Journal of Psychiatry 2009;166:653–661. 

54. Hoffmann P. Physical activity and mental health. In: Morgan 

WP, editor. Physical activity and mental health. Series in 

health psychology and behavioural medicine. Philadelphia, 

PA: Taylor & Francis; 1997. pp 163–177. 

55. Kraemer WJ, Dziados JE, Marchitelli LJ, Gordon SE, 

Harman EA, Mello R, et al. Effects of different 

heavy-resistance exercise protocols on plasma beta-endorphin 

concentrations. Journal of Applied Physiology 1993;74: 

450–459. 

56. Schwarz L, Kindermann W. Beta-endorphin, adrenocorticotropic 

hormone, cortisol and catecholamines during aerobic 

and anaerobic exercise. European Journal of Applied 

Physiology and Occupational Physiology 1990;61:165–171. 

57. Schwarz L, Kindermann W. Changes in beta-endorphin 

levels in response to aerobic and anaerobic exercise. Sports 

Medicine 1992;13:25–36. 

58. Guskiewicz KM, McCrea M, Marshall SW, Cantu RC, 

Randolph C, Barr W, et al. Cumulative effects associated 

with recurrent concussion in collegiate football players: The 

NCAA Concussion Study. JAMA: The Journal of the 

American Medical Association 2003;290:2549–2555. 

59. Kristman VL, Tator CH, Kreiger N, Richards D, 

Mainwaring L, Jaglal S, et al. Does the apolipoprotein 

epsilon 4 allele predispose varsity athletes to concussion? A 

prospective cohort study. Clinical Journal of Sport Medicine 

2008;18:322–328. 

60. Iverson GL, Gaetz M, Lovell MR, Collins MW. Cumulative 

effects of concussion in amateur athletes. Brain Injury 

2004;18:433–443. 

61. Reeves DL, Winter KP, Bleiberg J, Kane RL. ANAM 

genogram: Historical perspectives, description, and current 

endeavors. Archives of Clinical Neuropsychology 

2007;22(Suppl 1):S15–S37. 

62. Nixon H. A social network analysis of influences on athletes 

to play with pain and injuries. Journal of Sport and Social 

Issues 1992;16:127–135. 

63. Driver S, Ede A. Impact of physical activity on mood after 

TBI. Brain Injury 2009;23:203–212.

Emotional response to sport concussion compared to ACL injury

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?