The role of the hippocampus and prefrontal cortex in imagining the future: Insights from studies of patients with focal brain lesions

This article focuses on the neural and cognitive component processes that support the ability to imagine the future (episodic future thinking), which has recently been assumed to rely on the reconstructive nature of the episodic memory system. Functional neuroimaging studies have demonstrated the presence of a common core network, which underlies autobiographical remembering and future thinking. This network includes many regions traditionally associated with memory, such as the hippocampus and areas in the prefrontal cortex. However, inconsistent findings have emerged from recent studies of episodic future thinking in patients with amnesia and hippocampal damage, suggesting that imagining the future may not be entirely dependent on this structure. The existing evidence for impairments in future thinking in patients with prefrontal damage is at best either indirect, coming from studies of impaired planning and decision-making, or rest on a few case reports. Thus, the precise role of the hippocampus and prefrontal cortex in future thinking remains an open question. In this review, I consider findings from studies of patients with focal brain lesions with respect to current theoretical accounts for different component processes supporting the ability to envision the future and discuss the discrepant results within the literature.