March 14, 2018 Software Open Access

COCOHA Matlab Toolbox

Wong, Daniel D.E.; Hjortkjær, Jens; Ceolini, Enea; Cheveigné, Alain de

The COCOHA Matlab Toolbox is a coding framework internally shared within the COCOHA project. It was written to standardize MATLAB data storage and decoding analysis for the project. The data structure is based loosely on FieldTrip’s, but allows for the storage of multiple data sources (e.g. audio/EEG) and provides flexibility in defining dimensions (e.g. channel, time, frequency, rate, scale, etc). Moreover, function calls that modify the contents of the data structure will append their user-defined parameters to the data.cfg cell array. This allows for traceability of results.

The functions in the toolbox allow for external functions to operate on the data structure in a robust and standardized way.

The MATLAB components are designed for offline prototyping of decoding strategies. On the other hand, realtime processing is primarily implemented with OpenViBE Python scripts. OpenViBE is used as it provides drift correction, and its support for object-oriented programming allows better modularity.

The toolbox is not designed to replace FieldTrip for more traditional M/EEG analyses, but rather as a means to supplement such analyses with a support for decoding models. As such FieldTrip import capability is provided (and export capability is still pending).