title: Memory and reward systems coproduce 'nostalgic' experiences in the brain.
abstract: People sometimes experience an emotional state known as 'nostalgia', which involves experiencing predominantly positive emotions while remembering autobiographical events. Nostalgia is thought to play an important role in psychological resilience. Previous neuroimaging studies have shown involvement of memory and reward systems in such experiences. However, it remains unclear how these two systems are collaboratively involved with nostalgia experiences. Here, we conducted a functional magnetic resonance imaging study of healthy females to investigate the relationship between memory-reward co-activation and nostalgia, using childhood-related visual stimuli. Moreover, we examined the factors constituting nostalgia and their neural correlates. We confirmed the presence of nostalgia-related activity in both memory and reward systems, including the hippocampus (HPC), substantia nigra/ventral tegmental area (SN/VTA), and ventral striatum (VS). We also found significant HPC-VS co-activation, with its strength correlating with individual 'nostalgia tendencies'. Factor analyses showed that two dimensions underlie nostalgia: emotional and personal significance and chronological remoteness, with the former correlating with caudal SN/VTA and left anterior HPC activity, and the latter correlating with rostral SN/VTA activity. These findings demonstrate the cooperative activity of memory and reward systems, where each system has a specific role in the construction of the factors that underlie the experience of nostalgia.
authors.affiliation: Department of Frontier Health Science, Division of Human Health Sciences, Graduate School of Tokyo Metropolitan University, Tokyo, Japan, Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan, Division of Medical Neuroimage Analysis, Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan, and.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Oba
authors.affiliation: Department of Frontier Health Science, Division of Human Health Sciences, Graduate School of Tokyo Metropolitan University, Tokyo, Japan.
authors.forename: Madoka
authors.initials: M
authors.lastname: Noriuchi
authors.affiliation: Department of Frontier Health Science, Division of Human Health Sciences, Graduate School of Tokyo Metropolitan University, Tokyo, Japan, Department of Physical Therapy, Faculty of Medical Sciences, Teikyo University of Science, Uenohara, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Atomi
authors.affiliation: Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan.
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Moriguchi
authors.affiliation: Department of Frontier Health Science, Division of Human Health Sciences, Graduate School of Tokyo Metropolitan University, Tokyo, Japan, ykikuchi@tmu.ac.jp.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kikuchi
mesh_terms: D004644:Emotions / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D064368:Healthy Volunteers; D006624:Hippocampus / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008568:Memory / Q000502:physiology*; D061212:Memory, Episodic; D009434:Neural Pathways / Q000502:physiology; D010775:Photic Stimulation; D012201:Reward; D013378:Substantia Nigra / Q000502:physiology; D066328:Ventral Striatum / Q000502:physiology; D017557:Ventral Tegmental Area / Q000502:physiology; D055815:Young Adult
keywords: autobiographical memory; fMRI; nostalgia; resilience; reward