See comment in PubMed Commons belowJ Int Neuropsychol Soc. 2002 Jan;8(1):37-47.Perception of illness: nonspecificity of postconcussion syndrome symptom expectation.Gunstad J1, Suhr JA.Author information1Department of Psychology, Ohio University, Athens 45701, USA.AbstractA growing number of studies show postconcussion syndrome (PCS) symptom report is influenced by factors other than head injury, s