Mild traumatic brain injury (mTBI), commonly known as concussion, is the most common type of traumatic brain injury. Along with impaired cognitive function, mTBI causes an array of symptoms, including headaches, fatigue, depression, anxiety, and irritability, referred to as post-concussion syndrome (PCS). The time it takes for symptoms to resolve in the majority of individuals is thought to be approximately three months; however, some individuals continue to experience symptoms beyond that time period. Those with persistent symptoms are said to experience persistent post-concussion syndrome.
A widely cited figure suggests that only 15 percent of individuals experiencing a first-time concussion will go on to experience long-term cognitive impairment. A recently published research article suggests that this number is likely a gross underestimation.