Back in the Game: Study Links Negative Mood Disturbances to Sports Concussions

Researchers from the Toronto Rehabilitation Institute (Toronto Rehab) and the University of Toronto (U of T) have documented for the first time that negative mood disturbances such as depression and confusion can be a direct result of concussions caused by sports-related head injuries.

The study, which appeared in the March issue of the Journal of Sport & Exercise Psychology, found a causal link between sports concussion and subsequent emotional distress by charting the course of emotional recovery of concussed athletes. The researchers found that concussed athletes were not emotionally different from their teammates before an injury, but were more depressed and confused than uninjured peers after sustaining a concussion.

“This research is an exciting first step in our exploration of how mood interacts with cognitive deficits that often accompany concussion,” says Sean Bisschop, the project’s research coordinator and psychometrist in Toronto Rehab’s Neurology Service. “These findings let people know that emotional changes are common after concussion and that they should report mood changes to their clinician, just like any other symptom of concussion.”

According to Lynda Mainwaring, a psychologist and associate professor in U of T’s Faculty of Physical Education and Health, there has been little research into the emotional impact of concussions and subsequent recovery. The study will help clinicians determine when patients have completely recovered from a concussion and are able to resume athletic activities.

Researchers at Toronto Rehab and the University of Toronto note that the data they have generated with otherwise healthy concussed athletes who are motivated to return to play, could serve as a benchmark of emotional recovery for anyone who sustains a concussion not only athletes.

About 20-25% of athletes involved in high-risk sports may experience one or more concussions of varying severity each year. Athletes who return to high-risk activities too soon after a concussion are thought to be at greater risk of a second, potentially more dangerous injury.

The study also found that the depression, confusion and total mood disturbances that resulted from the concussion usually disappeared within three weeks. There were different rates of decrease for each emotion- depression resolved in approximately seven days while confusion and total mood disturbance took seventeen to twenty-one days. Post-injury mood disturbances did not appear to be a result of the injured athlete’s pre-injury emotional state.

Three groups were studied: concussed athletes, uninjured teammates of the concussed athletes and healthy, physically active undergraduate students. Baseline mood state for athletes (members of U of T Varsity sports teams) was measured during a pre-season medical and neurological assessment. Those athletes who suffered a concussion during the season were then repeatedly reassessed in the weeks after injury.

The U of T/Toronto Rehab Varsity Athlete Concussion Program is just one study in Toronto Rehab’s interprofessional neuro rehabilitation research effort. One collaborative project associated with the Concussion Program includes helping researchers in the US test sophisticated software called ANAM (Automated Neuropsychological Assessment Metrics), which can be used to assess an individual’s cognitive functioning. The software was developed to assess changes in mental functioning of U.S Air Force fighter pilots, astronauts on the space shuttle, submariners and infantry related to adverse or harsh environmental conditions.

“Eventually, a program like ANAM could be a significant piece of Internet-based clinical assessments being developed at Toronto Rehab. This way, a patient in Northern Ontario who doesn’t have easy access to a neuropsychologist could complete a clinical assessment that they might not otherwise receive,” says Bisschop.

Concussion, or mild traumatic brain injury (MTBI), can be caused by a sudden jolt to the brain that can lead to an alteration of consciousness that does not necessarily cause someone to lose consciousness. Physical symptoms of concussion include blurred vision, headache, dizziness and loss of coordination.

For more information about Toronto Rehab, please visit our Web site at