Hippocampal place cells can encode multiple trial-dependent features through rate remapping Journal Article

Author(s): Allen, Kevin; Rawlins, J Nick; Bannerman, David M; Csicsvári, József
Article Title: Hippocampal place cells can encode multiple trial-dependent features through rate remapping
Affiliation IST Austria
Abstract: The activity of hippocampal pyramidal cells reflects both the current position of the animal and information related to its current behavior. Here we investigated whether single hippocampal neurons can encode several independent features defining trials during a memory task. We also tested whether task-related information is represented by partial remapping of the place cell population or, instead, via firing rate modulation of spatially stable place cells. To address these two questions, the activity of hippocampal neurons was recorded in rats performing a conditional discrimination task on a modified T-maze in which the identity of a food reward guided behavior. When the rat was on the central arm of the maze, the firing rate of pyramidal cells changed depending on two independent factors: (1) the identity of the food reward given to the animal and (2) the previous location of the animal on the maze. Importantly, some pyramidal cells encoded information relative to both factors. This trial-type specific and retrospective coding did not interfere with the spatial representation of the maze: hippocampal cells had stable place fields and their theta-phase precession profiles were unaltered during the task, indicating that trial-related information was encoded via rate remapping. During error trials, encoding of both trial-related information and spatial location was impaired. Finally, we found that pyramidal cells also encode trial-related information via rate remapping during the continuous version of the rewarded alternation task without delays. These results suggest that hippocampal neurons can encode several task-related cognitive aspects via rate remapping.
Journal Title: Journal of Neuroscience
Volume: 32
Issue 42
ISSN: 1529-2401
Publisher: Society for Neuroscience  
Date Published: 2012-10-17
Start Page: 14752
End Page: 14766
DOI: 10.1523/JNEUROSCI.6175-11.2012
Notes: J.C. was supported by a MRC Intramural Programme Grant (U138197111) and a European Research Council Starter Grant (281511). K.A. held a Wellcome Trust PhD studentship and a Humboldt Research Fellowship for Postdoctoral Researchers. D.M.B. was supported by Wellcome Trust Senior Fellowships (074385 and 087736).
Open access: yes (repository)