title: Human aging alters the neural computation and representation of space.
abstract: The hippocampus and striatum are core neural circuits involved in spatial learning and memory. Although both neural systems support spatial navigation, experimental and theoretical evidence indicate that they play different roles. In particular, whereas hippocampal place cells generate allocentric neural representations of space that are sensitive to geometric information, striatum-dependent learning is influenced by local landmarks. How human aging affects these different neural representations, however, is still not well understood. In this paper, we combined virtual reality, computational modeling, and neuroimaging to investigate the effects of age upon the neural computation and representation of space in humans. We manipulated the geometry and local landmarks of a virtual environment and examined the effects on memory performance and brain activity during spatial learning. In younger adults, both behavior and brain activity in the medial-temporal lobe were consistent with predictions of a computational model of hippocampus-dependent boundary processing. In contrast, older adults' behavior and medial-temporal lobe activity were primarily influenced by local cue information, and spatial learning was more associated with activity in the caudate nucleus rather than the hippocampus. Together these results point to altered spatial representations and information processing in the hippocampal-striatal circuitry with advancing adult age, which may contribute to spatial learning and memory deficits associated with normal and pathological aging.
authors.affiliation: Max Planck Institute for Human Development, Center for Lifespan Psychology, 14195 Berlin, Germany; Princeton University, Princeton Neuroscience Institute, Princeton, NJ 08544, USA; Humboldt-Universität zu Berlin, Department of Psychology, 10099 Berlin, Germany. Electronic address: nschuck@princeton.edu.
authors.forename: Nicolas W
authors.initials: NW
authors.lastname: Schuck
authors.affiliation: Radboud University, Donders Institute for Brain, Cognition and Behaviour, 6525 Nijmegen, The Netherlands.
authors.forename: Christian F
authors.initials: CF
authors.lastname: Doeller
authors.affiliation: University of Michigan, Department of Psychology, Ann Arbor, MI 48109, USA.
authors.forename: Thad A
authors.initials: TA
authors.lastname: Polk
authors.affiliation: Max Planck Institute for Human Development, Center for Lifespan Psychology, 14195 Berlin, Germany.
authors.forename: Ulman
authors.initials: U
authors.lastname: Lindenberger
authors.affiliation: Max Planck Institute for Human Development, Center for Lifespan Psychology, 14195 Berlin, Germany; TU Dresden, Department of Psychology, Chair of Lifespan Developmental Neuroscience, 01062 Dresden, Germany.
authors.forename: Shu-Chen
authors.initials: SC
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D001921:Brain / Q000502:physiology*; D002421:Caudate Nucleus / Q000502:physiology; D006624:Hippocampus / Q000502:physiology; D006801:Humans; D008297:Male; D008959:Models, Neurological; D013028:Space Perception / Q000502:physiology*; D065853:Spatial Learning / Q000502:physiology*; D065852:Spatial Memory / Q000502:physiology*; D065854:Spatial Navigation / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology; D014584:User-Computer Interface
keywords: Aging; Hippocampus; Memory; Place cells; Spatial navigation; Striatum