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142 nips-2001-Orientational and Geometric Determinants of Place and Head-direction

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Author: Neil Burgess, Tom Hartley

Abstract: We present a model of the firing of place and head-direction cells in rat hippocampus. The model can predict the response of individual cells and populations to parametric manipulations of both geometric (e.g. O'Keefe & Burgess, 1996) and orientational (Fenton et aI., 2000a) cues, extending a previous geometric model (Hartley et al., 2000). It provides a functional description of how these cells' spatial responses are derived from the rat's environment and makes easily testable quantitative predictions. Consideration of the phenomenon of remapping (Muller & Kubie, 1987; Bostock et aI., 1991) indicates that the model may also be consistent with nonparametric changes in firing, and provides constraints for its future development. 1

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Summary: the most important sentenses genereted by tfidf model

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1 Orientational and geometric determinants place and head- Neil Burgess & Tom Hartley Institute of Cognitive Neuroscience & Department of Anatomy, UCL 17 Queen Square, London WCIN 3AR, UK n. [sent-1, score-0.349]

2 uk Abstract We present a model of the firing of place and head-direction cells in rat hippocampus. [sent-8, score-1.014]

3 The model can predict the response of individual cells and populations to parametric manipulations of both geometric (e. [sent-9, score-0.538]

4 O'Keefe & Burgess, 1996) and orientational (Fenton et aI. [sent-11, score-0.288]

5 , 2000a) cues, extending a previous geometric model (Hartley et al. [sent-12, score-0.313]

6 It provides a functional description of how these cells' spatial responses are derived from the rat's environment and makes easily testable quantitative predictions. [sent-14, score-0.449]

7 Consideration of the phenomenon of remapping (Muller & Kubie, 1987; Bostock et aI. [sent-15, score-0.177]

8 , 1991) indicates that the model may also be consistent with nonparametric changes in firing, and provides constraints for its future development. [sent-16, score-0.142]

9 1 Introduction 'Place cells' recorded in the hippocampus of freely moving rats encode the rat's current location (O'Keefe & Dostrovsky, 1971; Wilson & McNaughton, 1993). [sent-17, score-0.354]

10 In open environments a place cell will fire whenever the rat enters a specific portion of the environment (the 'place field'), independent of the rat's orientation (Muller et aI. [sent-18, score-1.679]

11 This location-specific firing appears to be present on the rat's first visit to an environment (e. [sent-20, score-0.412]

12 Hill, 1978), and does not depend on the presence of local cues such as odors on the floor or walls. [sent-22, score-0.309]

13 The complementary pattern of firing has also been found in related brain areas: 'head-direction cells' that fire whenever the rat faces in a particular direction independent of its location (Taube et aI. [sent-23, score-1.288]

14 Experiments involving consistent rotation of cues at or beyond the edge of the environment (referred to as 'distal' cues) produce rotation of the entire place (O'Keefe & Speakman, 1987; Muller et aI. [sent-25, score-1.133]

15 Rotating cues within the environment does not produce this effect (Cressant et aI. [sent-28, score-0.625]

16 Here we suggest a predicitive model of the mechanisms underlying these spatial responses. [sent-30, score-0.082]

17 2 Geometric influences given consistent orientation Given a stable directional reference (e. [sent-31, score-0.395]

18 stable distal cues across trials), fields are determined by inputs tuned to detect extended obstacles or boundaries at particular bearings. [sent-33, score-0.859]

19 That is, they respond whenever a boundary or obstacle occurs at a given distance along a given allocentric direction, independent of the rat's orientation. [sent-34, score-0.409]

20 These inputs are referred to below as putative 'boundary vector cells' (BVCs). [sent-35, score-0.205]

21 The functional form of these inputs has been estimated by recording from the same place cell in several environments of differing geometry within the same set of distal orientation cu~s (O'Keefe & Burgess, 1996; Hartley et al. [sent-36, score-1.039]

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