title: Medial Temporal Lobe Contributions to Episodic Future Thinking: Scene Construction or Future Projection?
abstract: Previous research has shown that the medial temporal lobes (MTL) are more strongly engaged when individuals think about the future than about the present, leading to the suggestion that future projection drives MTL engagement. However, future thinking tasks often involve scene processing, leaving open the alternative possibility that scene-construction demands, rather than future projection, are responsible for the MTL differences observed in prior work. This study explores this alternative account. Using functional magnetic resonance imaging, we directly contrasted MTL activity in 1) high scene-construction and low scene-construction imagination conditions matched in future thinking demands and 2) future-oriented and present-oriented imagination conditions matched in scene-construction demands. Consistent with the alternative account, the MTL was more active for the high versus low scene-construction condition. By contrast, MTL differences were not observed when comparing the future versus present conditions. Moreover, the magnitude of MTL activation was associated with the extent to which participants imagined a scene but was not associated with the extent to which participants thought about the future. These findings help disambiguate which component processes of imagination specifically involve the MTL.
authors.affiliation: Memory Disorders Research Center, VA Boston Healthcare System, Boston, MA 02130, USA.|Neuroimaging Research for Veterans Center (NeRVe), VA Boston Healthcare System, Boston, MA 02130, USA.|Department of Psychiatry, Boston University School of Medicine, Boston, MA 02118, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Palombo
authors.affiliation: Memory Disorders Research Center, VA Boston Healthcare System, Boston, MA 02130, USA.|Neuroimaging Research for Veterans Center (NeRVe), VA Boston Healthcare System, Boston, MA 02130, USA.|Department of Psychiatry, Boston University School of Medicine, Boston, MA 02118, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Hayes
authors.affiliation: Memory Disorders Research Center, VA Boston Healthcare System, Boston, MA 02130, USA.|Neuroimaging Research for Veterans Center (NeRVe), VA Boston Healthcare System, Boston, MA 02130, USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Peterson
authors.affiliation: Memory Disorders Research Center, VA Boston Healthcare System, Boston, MA 02130, USA.|Department of Psychiatry, Boston University School of Medicine, Boston, MA 02118, USA.|Department of Psychology, Wellesley College, Wellesley, MA 02481, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Keane
authors.affiliation: Memory Disorders Research Center, VA Boston Healthcare System, Boston, MA 02130, USA.|Neuroimaging Research for Veterans Center (NeRVe), VA Boston Healthcare System, Boston, MA 02130, USA.|Department of Psychiatry, Boston University School of Medicine, Boston, MA 02118, USA.
authors.forename: M
authors.initials: M
authors.lastname: Verfaellie
mesh_terms: D000293:Adolescent; D005260:Female; D005544:Forecasting; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010775:Photic Stimulation / Q000379:methods*; D011897:Random Allocation; D011930:Reaction Time / Q000502:physiology*; D013702:Temporal Lobe / Q000000981:diagnostic imaging* / Q000502:physiology*; D013850:Thinking / Q000502:physiology*; D055815:Young Adult
keywords: future thinking; hippocampus; imagination; medial temporal lobes; scene construction