DOI: 10.5281/zenodo.10460297
title: Cholinergic modulation of rearing in rats performing a spatial memory task

description: Scripts, raw and processed data, and figures from: Cassity, Choi, et al., (2024) Cholinergic modulation of rearing in rats performing a spatial memory task European Journal of Neuroscience. Published abstract is pasted below for ease of reference regarding the substance of this work.

 

 

Contents:

** NOTE ** Shortcut: If you are only looking for the raw behavioral tracking data, it can found in data tables stored in: results/*rearDat*.mat files. (e.g., rump_pos & nose_pos).

 

Overview:

·      figs.zip: figure images and data tables for all results shown in figures

 

·      scripts.zip: all custom matlab scripts used to perform analyses and generate figures

 

·      Results.zip: data collection logs and matlab *.mat files containing intermediate results and statistical results

 

File naming conventions:

            Inclusion of ‘halo’ indicates data from a rat transfected with halorhodopsin

            Inclusion of ‘rptr’ indicates data from a rat transfected with reporter only

            Inclusion of ‘real’ indicates that they received real laser stimulation (laser powered on)

                        note: ‘real’ is also called ‘stim’ in some scripts

            Inclusion of ‘sham’ indicates that no laser stimulation was given (laser was powered off)

                        note: ‘sham’ is also called ‘ctrl’ in some scripts

            Inclusion of ‘diff’ indicates the difference between the key conditions (e.g., sham vs real)

 

Data structure conventions:

            Most data structures include data for the ‘stim arms’ and ‘non-stim arms’ for a given rat / session / etc. and thus come in pairs of columns. The respective scripts that create each saved output will indicate what each column represents.

 

Details:

·      Figs

o   Subfolders for each figure or set of figures containing relevant *png/*ps files used in assembling composite figure images.

o   *.mat file in each respective subfolder containing the raw plotted data. Each point on a figure corresponds to one point in these files.

·      Scripts

o   The scripts titled ‘LoadProcessedBehaviorDataAcrossRats. . ..m’ perform the analysis from beginning to end. All other scripts should be called at some point or another while going through these.

o   There are four subfolders:

§  figureGeneration: the scripts used to ready the data and plot the results for each figure of the manuscript.

§  labelingCode: reference information used to parse or otherwise make sense of the data stored elsewhere.

§  analyses: the main substantive processing code

§  utils: supporting code

·      Results

o   *rearDat*.mat files contain the most raw forms of data including the raw DeepLabCut output for nose and rump, as well as intermediate forms of the data including logs of when the rats were rearing or in one arm (ROI) versus another of the maze, and details about the trial (which arms were set to trigger the laser (stimArms) versus not (nonStimArms)).

o   *Data.mat files contain the aggregated results such as time spent rearing, numbers of rears, dwell time etc. for each session for each rat.

o   stats*.mat files contain the results of performing statistical comparisons over the aggregated results.

Abstract:

Spatial memory encoding depends in part on cholinergic modulation. How acetylcholine supports spatial memory encoding is not well understood. Prior studies indicate that acetylcholine release is correlated with exploration, including epochs of rearing onto hind legs. Here, to test whether elevated cholinergic tone increases the probability of rearing, we tracked rearing frequency and duration while optogenetically modulating the activity of choline acetyltransferase containing (i.e., acetylcholine producing) neurons of the medial septum in rats performing a spatial working memory task (n = 17 rats). The cholinergic neurons were optogenetically inhibited using halorhodopsin for the duration that rats occupied two of the four open arms during the study phase of an 8-arm radial arm maze win-shift task. Comparing rats’ behavior in the two arm types showed that rearing frequency was not changed but the average duration of rearing epochs became significantly longer. This effect on rearing was observed during optogenetic inhibition but not during sham inhibition or in rats that received infusions of a fluorescent reporter virus (i.e., without halorhodopsin; n = 6 rats). Optogenetic inhibition of cholinergic neurons during the pre-trial waiting phase had no significant effect on rearing, indicating a context-specificity of the observed effects. These results are significant in that they indicate that cholinergic neuron activity in the medial septum is correlated with rearing not because it motivates an exploratory state but because it contributes to the processing of information acquired while rearing.