DOI: 10.5061/dryad.jdfn2z3dj
title: Theta dominates cross-frequency coupling in hippocampal-medial entorhinal circuit during awake-behavior in rats

description: Hippocampal theta and gamma rhythms are hypothesized to play a role in the
 physiology of higher cognition. Prior research has reported that an offset
 in theta cycles between the entorhinal cortex, CA3, and CA1 regions
 promotes independence of population activity across the hippocampus. In
 line with this idea, it has recently been observed that CA1 pyramidal
 cells can establish and maintain coordinated place cell activity
 intrinsically, with minimal reliance on afferent input. Counter to these
 observations is the contemporary hypothesis that CA1 neuron activity is
 driven by a gamma oscillation arising from the medial entorhinal cortex
 (MEC) that relays information by providing precisely timed synchrony
 between MEC and CA1. Reinvestigating this in rats during appetitive track
 running, we found that theta is the dominant frequency of cross-frequency
 coupling between the MEC and hippocampus, with hippocampal gamma largely
 independent of entorhinal gamma.
description: # Theta dominates cross-frequency coupling in hippocampal-medial
 entorhinal circuit during awake-behavior in rats Dataset DOI:
 [10.5061/dryad.jdfn2z3dj](10.5061/dryad.jdfn2z3dj) ## Description of the
 data and file structure Containing Matlab codes to generate Fig1. D and
 supplementary fig 5 in the manuscript. Run
 "coherence_evomodel.m" to get Fig1. D Run
 "cohvartest.m" to get supplementary fig 5 There are 8 animals
 [r695,r730,r779,r782,r889,r1096,r1224,r1225] The LFP files are named as
 r#animalnumberLFP.mat It's a structure called EEG with EEG.Axis{1} as
 timestamps and EEG.Data being LFP recordings. In EEG.Data, rows are time
 stamps and columns are channels. The position files are named as
 r#animalnumberPos.mat It's a structure called Pos with Pos.Axis{1}
 being timestamps. In Pos.Data, rows are timestamps and columns 1 & 2
 are X and Y coordinates. Channel information for each animal can be found
 in ChannelInfo_HPCMEC.xlsx, which include channels in HPC and MEC, as well
 as HPC layer information confirmed by ripple CSD analysis. In the table,
 rows are individual animals, columns are channels numbers in corresponding
 MEC and hippocampal layers. The preprocessed data are named as
 r#animalnumber_prep.mat. It is a matlab structure names "EEG"
 with length equals to number of LFP segments. For each LFP segment, it has
 the length of around 1 second. EEG(i) is the ith LFP segments and it has
 following fields: EEG(i).Data should be a 2048*64(or 128) matrix with row
 being time steps and columns being channels. Some animals have 64 channels
 and some have 128 channels. The mapping between channel number of brain
 stratum information can be found in ChannelInfo_HPCMEC.xlsx.
 EEG(i).Axis{1} should be a 1*2048 vector which contains the time stamps.
 EEG(i).Axis{2} should be a 1*64(or 128) vector which just contain channel
 numbers (should just be 1 to 64 or 1 to 128). EEG(i).Name just tell you
 dimension 1 is time, and dimension 2 is channel number (not important).
 EEG(i).Frequency is the sampling frequency, somehow we use 2000, should
 not cause big issue. EEG(i).Period is the inverse of sampling frequency.
 EEG(i).V should be a 2048*1 vector being the interpolated velocity of the
 animal at each LFP time stamp. EEG(i).Vmean and EEG(i).Vstd gives the mean
 and STD value of velocity in this LFP segments. We may exclude recording
 in sleep box from these preprocessed LFP. r1224_EEG_Fragment*_*0946.fig is
 a figure example of preprocessed LFP segments across all the channels from
 rat1224. It can be directly loaded into Matlab. ## Version changes
 **03-Apr-2025:** Added raw LFP and position recoding of 7 more animals,
 including the preprocessed LFP data for all the animals.
 Added  ChannelInfo_HPCMEC.xlsx describing layer information across
 channels. Added one example plot of preprocessed LFP across channel for
 rat 1224.