Patients with bipolar disorder show a selective deficit in the episodic simulation of future events

A substantial body of evidence suggests that autobiographical recollection and simulation of future happenings activate a shared neural network. Many of the neural regions implicated in this network are affected in patients with bipolar disorder (BD), showing altered metabolic functioning and/or structural volume abnormalities. Studies of autobiographical recall in BD reveal overgeneralization, where autobiographical memory comprises primarily factual or repeated information as opposed to details specific in time and in place and definitive of re-experiencing. To date, no study has examined whether these deficits extend to future event simulation. We examined the ability of patients with BD and controls to imagine positive, negative and neutral future events using a modified version of the Autobiographical Interview (Levine, Svoboda, Hay, Winocur, & Moscovitch, 2002) that allowed for separation of episodic and non-episodic details. Patients were selectively impaired in imagining future positive, negative, and neutral episodic details; simulation of non-episodic details was equivalent across groups.