Deficits in past remembering extend to future imagining in a case of developmental amnesia

Patient and neuroimaging studies report that the ability to remember past personal experiences and the ability to envision future personal experiences are interconnected. Loss of episodic memory is typically accompanied by loss of future imagining, and engaging in either activity recruits common brain areas. The relationship between episodic memory and future imagining is also suggested by their co-emergence in ontogenetic development. However, it is unknown whether a failure of one ability to emerge in early development precludes the development of the other ability. To investigate this possibility, we tested H.C., a young woman with amnesia of developmental origin associated with bilateral hippocampal loss, and demographically matched controls on an adapted version of the Autobiographical Interview using Galton-Crovitz cueing. In response to cue words, participants described both past personal events and imagined future personal events that occurred, or could occur, in near and distant time periods. Results indicated a parallel pattern of impairment for both past and future event generation in H.C., such that her narratives of both types of events were similarly deficient. These results indicate that mental time travel can be compromised in hippocampal amnesia, whether acquired in early or later life, possibly as a result of a deficit in reassembling and binding together details of stored information from earlier episodes.