Hypnosis for acquired brain injury: Four patient cases and five testable predictions

Recent studies have found large treatment effects of hypnotic suggestion on cognitive impairment following acquired brain injury. However, little is known about the underlying mechanisms of these effects. A general framework is presented in which (1) a substantial part of cognitive brain-injury sequelae can be attributed to negative self-expectancies, and (2) hypnosis is a powerful way to manipulate negative self-expectancies. Four cases exemplify and add to this framework. First, mental imagery of brain recovery can be effective even if it does not correspond to the "real" physical brain injury. Second, some patients do not subjectively experience improvement despite large objective improvements. Third, some patients inhibit positive treatment effects in contexts where this is incentivized, e.g., when they are evaluated for monetary compensation during an ongoing litigation. Fourth, pre-injury autobiographical memories may be an important precondition for positive treatment effects. We conclude with five testable predictions, which can further optimize hypnosis for acquired brain injury.