MOD - A Machine-learning optimal detection method.

These functions show the essential steps of using MOD for detecting EPSP/EPSCs as described in [1] and applied in [2].

In order to run this demo, the following software packages are needed:

Copyright © 2016-2022 Alois Schlögl, IST Austria

Downloads: https://pub.ist.ac.at/~schloegl/software/mod/mod-2.0.tar.xz https://pub.ist.ac.at/~schloegl/software/mod/mod-2.0.zip

The source code is also available as part of Biosig [3], in subdirectory …/t340_MachineLearningOptimalDetection/

References:

[1] Zhang X, Schlögl A, Vandael D, Jonas P, MOD: A novel machine-learning optimal-filtering method for accurate and efficient detection of subthreshold synaptic events in vivo. Journal of Neuroscience Methods, 2021. https://doi.org/10.1016/j.jneumeth.2021.109125

[2] Xiaomin Zhang, Alois Schlögl, Peter Jonas Selective Routing of Spatial Information Flow from Input to Output in Hippocampal Granule Cells, Neuron, 2020. https://doi.org/10.1016/j.neuron.2020.07.006 http://www.sciencedirect.com/science/article/pii/S0896627320305237

[3] Biosig - an Free and Ppen source software library for biomedical signal processing http://biosig.sourceforge.net/index.html

[4] The NaN-toolbox: A statistics and machine learning toolbox for Octave and Matlab® for data with and w/o MISSING VALUES encoded as NaN's. https://pub.ist.ac.at/~schloegl/matlab/NaN/

[5] SigViewer (v0.5.1 or v0.65+) https://github.com/cbrnr/sigviewer/commit/f62f8d9d16db8c5c89c0fc12563b20bf4ad2ab7f (Nov 18, 2020) or later. Binaries for windows are available here: https://pub.ist.ac.at/~schloegl/software/sigviewer/sigviewer-0.6.4-win64.exe

[6] https://pub.ist.ac.at/~schloegl/software/mod/

Content:

% demo - applying the method to the example data available from
%    https://pub.ist.ac.at/~schloegl/software/mod/
% results will be written into output/*
demo_mod.m
% An extended version with LOOM-based cross-validation, and two scorings 
%   is shown in 
demo_modx.m

% this is the core function for obtaining the parameters of 
    % from the MOD method  (filter coefficients, threshold, and delay)
mod_optimal_detection_filter.m

% storing the results in a GDF file for visualization with sigviewer
minidet2gdf.m

FAQ

How to apply it to your own data

This depends whether you want to build a detector for each cell, or whether you want to build a general classifier.

Cell-based classifier:

Check out demo_mod.m and address these items:

1) you need your raw data, and your scorings and adapt loading the data (lines 67-87) Please note, the scorings consists of two periods (one segment in the beginning, the other from the end) And you need to tell which periods are scored, when constructing the scoring trace lines 124-136.

2) In case you want to apply blanking of AP's, you need to detect them and replace them with NaN's (line 88-90, 115-123)

3) if you want to downsample your data, you can check the lines 92-114,

4) If you want to apply cross-validation, you should enable lines 140 - 194

That should do it. The main data processing of training the detection method happens in lines 199-213, the remainder storing the results, and in case you still have some HF noise in the raw detection trace, you might want to smooth it before doing the event detection.

General classifier:

Check out demo_modx.m and address these items:

1) loading of data, where is your data located, how to load it.
define the grouping information, this is useful for the cross-validation later

2) get the scorings, identify which parts of the data is scored

3) proprocessing, detection artifacts, AP etc. and remove (blank) those.

4) run training and testing procedure on the scored data, use Leave-one-out-method for cross-validation.

5) Build the general classifier from all scored data.

Is the output in the text file simply the event timings?

Yes, the event timing can be found in multiple outputs.

Changes

2022-03-02: - demomodx added - shows the use of leave-one-out-method for crossvalidation - add 6 data sets, with 2 scorings each - use accovfmex to speed up training step

2021-06-21: improve documentation

2021-03-12: first release: