Theta phase precession of grid and place cell firing in open environments

Jeewajee, A.; Barry, C.; Douchamps, V.; Manson, D.; Lever, C.; Burgess, N.

Abstract

Place and grid cells in the rodent hippocampal formation tend to fire spikes at successively earlier phases relative to the local field potential theta rhythm as the animal runs through the cell's firing field on a linear track. However, this ‘phase precession’ effect is less well characterized during foraging in two-dimensional open field environments. Here, we mapped runs through the firing fields onto a unit circle to pool data from multiple runs. We asked which of seven behavioural and physiological variables show the best circular–linear correlation with the theta phase of spikes from place cells in hippocampal area CA1 and from grid cells from superficial layers of medial entorhinal cortex. The best correlate was the distance to the firing field peak projected onto the animal's current running direction. This was significantly stronger than other correlates, such as instantaneous firing rate and time-in-field, but similar in strength to correlates with other measures of distance travelled through the firing field. Phase precession was stronger in place cells than grid cells overall, and robust phase precession was seen in traversals through firing field peripheries (although somewhat less than in traversals through the centre), consistent with phase coding of displacement along the current direction. This type of phase coding, of place field distance ahead of or behind the animal, may be useful for allowing calculation of goal directions during navigation.

Citation

Jeewajee, A., Barry, C., Douchamps, V., Manson, D., Lever, C., & Burgess, N. (2014). Theta phase precession of grid and place cell firing in open environments. Philosophical Transactions of the Royal Society B: Biological Sciences, 369(1635), Article 20120532. https://doi.org/10.1098/rstb.2012.0532

• Journal Article Type: Article
• Acceptance Date: Dec 20, 2013
• Online Publication Date: Feb 5, 2014
• Publication Date: Feb 5, 2014
• Deposit Date: Jan 18, 2017
• Publicly Available Date: Jan 19, 2017
• Journal: Philosophical Transactions of the Royal Society B: Biological Sciences
• Print ISSN: 0962-8436
• Electronic ISSN: 1471-2970
• Publisher: The Royal Society
• Peer Reviewed: Peer Reviewed
• Volume: 369
• Issue: 1635
• Article Number: 20120532
• DOI: https://doi.org/10.1098/rstb.2012.0532
• Public URL: https://durham-repository.worktribe.com/output/1388386