Computes the Phase Locking Value between all EEG channel pairs within a
specified frequency band. Each channel is bandpass filtered, instantaneous
phase is extracted via the Hilbert transform, and PLV is computed as the
mean resultant length of the phase difference distribution.
Usage
eegPLV(x, band = c(8, 13), assay_name = NULL)
Arguments
- x
A PhysioExperiment object with EEG data (2D: time x channels).
- band
Numeric vector of length 2 specifying the frequency band in Hz
for bandpass filtering before phase extraction (default: c(8, 13)
for alpha band).
- assay_name
Name of the input assay. If NULL, the default
assay is used.
Value
A data.frame with columns:
- channel1
Character or integer identifier of the first channel.
- channel2
Character or integer identifier of the second channel.
- plv
Numeric PLV value in [0, 1].
Details
$$PLV = |1/N \sum_{t=1}^{N} exp(i(\phi_x(t) - \phi_y(t)))|$$
References
Lachaux, J. P., et al. (1999). Measuring phase synchrony in brain signals.
Human Brain Mapping, 8(4), 194-208.
Examples
if (FALSE) { # \dontrun{
pe <- make_eeg(n_time = 5000, n_channels = 4, sr = 500)
plv_df <- eegPLV(pe, band = c(8, 13))
head(plv_df)
} # }