Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Gamma oscillatory firing reveals distinct populations of pyramidal cells in the CA1 region of the hippocampus

Senior, Timothy J., Huxter, John R., Allen, Kevin, O'Neill, Joseph and Csicsvari, Jozsef 2008. Gamma oscillatory firing reveals distinct populations of pyramidal cells in the CA1 region of the hippocampus. Journal of Neuroscience 28 (9) , pp. 2274-2286. 10.1523/JNEUROSCI.4669-07.2008

[img]
Preview
PDF - Published Version
Download (1MB) | Preview

Abstract

Hippocampal place cells that fire together within the same cycle of theta oscillations represent the sequence of positions (movement trajectory) that a rat traverses on a linear track. Furthermore, it has been suggested that the encoding of these and other types of temporal memory sequences is organized by gamma oscillations nested within theta oscillations. Here, we examined whether gamma-related firing of place cells permits such discrete temporal coding. We found that gamma-modulated CA1 pyramidal cells separated into two classes on the basis of gamma firing phases during waking theta periods. These groups also differed in terms of their spike waveforms, firing rates, and burst firing tendency. During gamma oscillations one group's firing became restricted to theta phases associated with the highest gamma power. Consequently, on the linear track, cells in this group often failed to fire early in theta-phase precession (as the rat entered the place field) if gamma oscillations were present. The second group fired throughout the theta cycle during gamma oscillations, and maintained gamma-modulated firing at different stages of theta-phase precession. Our results suggest that the two different pyramidal cell classes may support different types of population codes within a theta cycle: one in which spike sequences representing movement trajectories occur across subsequent gamma cycles nested within each theta cycle, and another in which firing in synchronized gamma discharges without temporal sequences encode a representation of location. We propose that gamma oscillations during theta-phase precession organize the mnemonic recall of population patterns representing places and movement paths.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Psychology
Publisher: Society for Neuroscience
ISSN: 0270-6474
Date of First Compliant Deposit: 31 January 2018
Date of Acceptance: 4 January 2008
Last Modified: 07 Feb 2018 16:35
URI: http://orca.cf.ac.uk/id/eprint/108634

Citation Data

Cited 102 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics