Causes

Some experts believe persistent post-concussive symptoms are caused by structural damage to the brain or disruption of the messaging system within the nerves, caused by the impact that caused the concussion.

Others believe persistent post-concussive symptoms are related to psychological factors. The most common symptoms — headache, dizziness and sleep problems — are similar to those often experienced by people diagnosed with depression, anxiety or post-traumatic stress disorder.

In many cases, both physical damage of brain trauma and emotional reactions to these effects play a role in the development of symptoms.

However, some research shows that certain factors are more common in people who develop persistent post-concussive symptoms compared with those who don't. These factors include a history of depression, anxiety, post-traumatic stress disorder, significant life stressors, a poor social support system and lack of coping skills.

More research is still needed to better understand how and why persistent post-concussive symptoms happen after some injuries and not others.