Individuals sustaining mild traumatic brain injuries often report a constellation of physical, cognitive, and emotional/behavioral symptoms referred to as post concussion symptoms (PCS). The most commonly reported post concussion symptoms are headache, dizziness, decreased concentration, memory problems, irritability, fatigue, visual disturbances, sensitivity to noise, judgment problems, depression, and anxiety. Although these PCS often resolve within one month, in some individuals PCS can persist from months to years following injury and may even be permanent and cause disability. When this cluster of PCS is persistent in nature, it is often called the post concussion syndrome or persistent PCS. Both physiological and psychological etiologies have been suggested as causes for persistent post concussion symptoms and this has led to much controversy and debate in the literature. Most investigators now believe that a variety of pre-morbid, injury-related, and post-morbid neuropathological and psychological factors contribute to the development and continuation of these symptoms in those sustaining mild traumatic brain injury (MTBI).

Ryan LM, Warden DL. Post concussion syndrome. Int Rev Psychiatry. 2003 Nov;15(4):310-6. doi: 10.1080/09540260310001606692. PMID: 15276952.