Convert an eeg_data
or eeg_epochs
object to using Current
Source Densities. This command uses a spherical spline algorithm (Perrin et
al., 1989) to compute scalp surface Laplacian/current source density
estimates of scalp potentials, a reference-free measure of electrical
activity that emphasises more local spatial features
compute_csd(data, ...) # S3 method for default compute_csd(data, ...) # S3 method for eeg_data compute_csd(data, m = 4, smoothing = 1e-05, scaling = 1, ...) # S3 method for eeg_epochs compute_csd(data, m = 4, smoothing = 1e-05, scaling = 1, ...)
data |
|
---|---|
... | Other parameters |
m | smoothing constraint (higher = more rigid splines) |
smoothing | lambda constant. Added to the Defaults to 1e-05 |
scaling | Default scaling (1) is uV / m^2. Note that this depends on the units of the electrode co-ordinates. |
default
: Default method to detect unknown classes.
eeg_data
: Transform eeg_data to CSD
eeg_epochs
: Transform eeg_data to CSD
[1] Perrin, F., Pernier, J., Bertrand, O., Echallier, J.F. (1989). Spherical splines for scalp potential and current density mapping. Electroencephalography and Clinical Neurophysiology, 72(2), 184-187. PMID: 2464490 [2] Kayser, J., Tenke, C.E. (2006). Principal components analysis of Laplacian waveforms as a generic method for identifying ERP generator patterns: I. Evaluation with auditory oddball tasks. Clinical Neurophysiology, 117(2), 348-368. [3] Kayser, J., Tenke, C.E. (2015). Issues and considerations for using the scalp surface Laplacian in EEG/ERP research: A tutorial review. International Journal of Psycholphysiology, 97(3), 189-209