mne.decoding.compute_ems

mne.decoding.compute_ems(epochs, conditions=None, picks=None, n_jobs=1, cv=None, verbose=None)[source]

Compute event-matched spatial filter on epochs.

This version of EMS [1] operates on the entire time course. No time window needs to be specified. The result is a spatial filter at each time point and a corresponding time course. Intuitively, the result gives the similarity between the filter at each time point and the data vector (sensors) at that time point.

Parameters
epochsinstance of mne.Epochs

The epochs.

conditionslist of str | None, default None

If a list of strings, strings must match the epochs.event_id’s key as well as the number of conditions supported by the objective_function. If None keys in epochs.event_id are used.

picksstr | list | slice | None

Channels to include. Slices and lists of integers will be interpreted as channel indices. In lists, channel type strings (e.g., ['meg', 'eeg']) will pick channels of those types, channel name strings (e.g., ['MEG0111', 'MEG2623'] will pick the given channels. Can also be the string values “all” to pick all channels, or “data” to pick data channels. None (default) will pick good data channels.

n_jobsint

The number of jobs to run in parallel (default 1). Requires the joblib package.

cvcross-validation object | str | None, default LeaveOneOut

The cross-validation scheme.

verbosebool, str, int, or None

If not None, override default verbose level (see mne.verbose() and Logging documentation for more).

Returns
surrogate_trialsndarray, shape (n_trials // 2, n_times)

The trial surrogates.

mean_spatial_filterndarray, shape (n_channels, n_times)

The set of spatial filters.

conditionsndarray, shape (n_classes,)

The conditions used. Values correspond to original event ids.

References

1

Aaron Schurger, Sebastien Marti, and Stanislas Dehaene, “Reducing multi-sensor data to a single time course that reveals experimental effects”, BMC Neuroscience 2013, 14:122

Examples using mne.decoding.compute_ems