Analysis code for detection of candidate spike-ripple events.
This MATLAB repository contains the data analysis method developed in:
C. J. Chu et al, "A semi-automated method for rapid detection of ripple events on interictal voltage discharges in the scalp electroencephalogram", Journal of Neuroscience Methods, Volume 277, 1 February 2017, Pages 46–55.
The analysis code is located in the file: spike_ripple_detector.m. This function accepts two inputs which specify the data (i.e., a single channel of EEG) and a time axis in units of seconds. A third optional input may also be included to specify the envelope threshold (default value is 0.85). This function returns two outputs. The first output is a structure, in which each entry contains the features of a candidate spike-ripple event. The second output returns additional diagnostics. This output may then be used as input to visualize and classify the candidate spike ripple events in the file: spike_ripple_visualizer.m
For example:
data = EEG; %where "EEG" corresponds to voltage data recorded from one scalp electrode.
Fs = 1000; %the sampling frequency in Hz.
t = (1:length(EEG))/Fs; %corresponding time axis.
[res,diagnostics] = spike_ripple_detector(EEG,t); %Call the function, and return the candidate spike-ripple events.
[expert_classify] = spike_ripple_visualizer(EEG,t,res,diagnostics) % Visualize and classify the candidate spike-ripple events.