title: Neural encoding of large-scale three-dimensional space-properties and constraints.
abstract: How the brain represents represent large-scale, navigable space has been the topic of intensive investigation for several decades, resulting in the discovery that neurons in a complex network of cortical and subcortical brain regions co-operatively encode distance, direction, place, movement etc. using a variety of different sensory inputs. However, such studies have mainly been conducted in simple laboratory settings in which animals explore small, two-dimensional (i.e., flat) arenas. The real world, by contrast, is complex and three dimensional with hills, valleys, tunnels, branches, and-for species that can swim or fly-large volumetric spaces. Adding an additional dimension to space adds coding challenges, a primary reason for which is that several basic geometric properties are different in three dimensions. This article will explore the consequences of these challenges for the establishment of a functional three-dimensional metric map of space, one of which is that the brains of some species might have evolved to reduce the dimensionality of the representational space and thus sidestep some of these problems.
authors.affiliation: Institute of Behavioural Neuroscience, Research Department of Experimental Psychology, Division of Psychology and Language Sciences, University College London , London, UK.
authors.forename: Kate J
authors.initials: KJ
authors.lastname: Jeffery
authors.affiliation: Institute of Behavioural Neuroscience, Research Department of Experimental Psychology, Division of Psychology and Language Sciences, University College London , London, UK.
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Wilson
authors.affiliation: Institute of Behavioural Neuroscience, Research Department of Experimental Psychology, Division of Psychology and Language Sciences, University College London , London, UK.
authors.forename: Giulio
authors.initials: G
authors.lastname: Casali
authors.affiliation: Clinical and Experimental Epilepsy, Institute of Neurology, Faculty of Brain Sciences, University College London , London, UK.
authors.forename: Robin M
authors.initials: RM
authors.lastname: Hayman
keywords: dimensions; grid cells; head direction cells; navigation; place cells; spatial cognition; theoretical model