Note
This page is a reference documentation. It only explains the function signature, and not how to use it. Please refer to the user guide for the big picture.
nilearn.glm.first_level.compute_regressor#
- nilearn.glm.first_level.compute_regressor(exp_condition, hrf_model, frame_times, con_id='cond', oversampling=50, fir_delays=None, min_onset=- 24)[source]#
This is the main function to convolve regressors with hrf model
- Parameters
- exp_conditionarray-like of shape (3, n_events)
yields description of events for this condition as a (onsets, durations, amplitudes) triplet
- hrf_model
str, function, list of functions, or None This parameter defines the HRF model to be used. It can be a string if you are passing the name of a model implemented in Nilearn. Valid names are:
‘spm’: This is the HRF model used in SPM. See
nilearn.glm.first_level.spm_hrf.‘spm + derivative’: SPM model plus its time derivative. This gives 2 regressors. See
nilearn.glm.first_level.spm_hrf, andnilearn.glm.first_level.spm_time_derivative.‘spm + derivative + dispersion’: Idem, plus dispersion derivative. This gives 3 regressors. See
nilearn.glm.first_level.spm_hrf,nilearn.glm.first_level.spm_time_derivative, andnilearn.glm.first_level.spm_dispersion_derivative.‘glover’: This corresponds to the Glover HRF. See
nilearn.glm.first_level.glover_hrf.‘glover + derivative’: The Glover HRF + time derivative. This gives 2 regressors. See
nilearn.glm.first_level.glover_hrf, andnilearn.glm.first_level.glover_time_derivative.‘glover + derivative + dispersion’: Idem, plus dispersion derivative. This gives 3 regressors. See
nilearn.glm.first_level.glover_hrf,nilearn.glm.first_level.glover_time_derivative, andnilearn.glm.first_level.glover_dispersion_derivative.‘fir’: Finite impulse response basis. This is a set of delayed dirac models.
It can also be a custom model. In this case, a function should be provided for each regressor. Each function should behave as the other models implemented within Nilearn. That is, it should take both t_r and oversampling as inputs and return a sample numpy array of appropriate shape.
Note
It is expected that spm standard and glover models would not yield large differences in most cases.
Note
In case of glover and spm models, the derived regressors are orthogonalized wrt the main one.
- frame_timesarray of shape (n_scans)
the desired sampling times
- con_idstring, optional, default is ‘cond’.
Identifier of the condition
- oversamplingint, optional
Oversampling factor to perform the convolution. Default=50.
- fir_delays[int] 1D-array-like, optional
Delays (in scans) used in case of a finite impulse response model.
- min_onsetfloat, optional
Minimal onset relative to frame_times[0] (in seconds) events that start before frame_times[0] + min_onset are not considered. Default=-24.
- Returns
- computed_regressorsarray of shape(n_scans, n_reg)
Computed regressors sampled at frame times.
- reg_nameslist of strings
Corresponding regressor names.
