Symptoms following mild head injury: expectation as aetiology.

TLDR

The study used a symptom checklist to have healthy participants report current symptoms, then imagine a mild head injury and endorse expected six‑month symptoms, and compared these expectations with actual symptoms reported by patients with head injuries. Participants’ imagined concussion symptoms formed a coherent cluster matching patients’ postconcussion syndrome, and symptom expectations explained as much variance as actual head injury, indicating a potential etiological role.

Abstract

An affective, somatic, and memory check-list of symptoms was administered to subjects who had no personal experience or knowledge of head injury. Subjects indicated their current experiences of symptoms, then imagined having sustained a mild head injury in a motor vehicle accident, and endorsed symptoms they expected to experience six months after the injury. The checklist of symptoms was also administered to a group of patients with head injuries for comparison. Imaginary concussion reliably showed expectations in controls of a coherent cluster of symptoms virtually identical to the postconcussion syndrome reported by patients with head trauma. Patients consistently underestimated the premorbid prevalence of these symptoms compared with the base rate in controls. Symptom expectations appear to share as much variance with postconcussion syndrome as head injury itself. An aetiological role is suggested.