What is the phase locking value?

Specifically, the phase locking value (PLV) is a measure of the phase synchrony between two time-series, which has been previously applied to resting state connectivity analysis in MEG (Ghuman et al., 2011). Here we employ PLV as a measure of frequency-specific relationships between cortical regions.

What is phase locking in EEG?

This can be anything, even a particular signature in the EEG signal, such as the phase of a slower oscillation. For example, you could extract epochs of gamma-band filtered data locked to the phase of theta oscillation or amplitude of delta oscillations; then compute PLV time course relative to these.

What is phase locking in the auditory system?

In the auditory system, phase locking refers to the fact that the probability of neuronal action potentials (spikes) varies as a function of the phase of low-frequency tones, low-frequency components of broadband sounds, or low-frequency fluctuations of the envelope (for review, see Joris et al., 2004; Heil and …

What does Hilbert transform do?

The Hilbert transform is a technique used to obtain the minimum-phase response from a spectral analysis. When performing a conventional FFT, any signal energy occurring after time t = 0 will produce a linear delay component in the phase of the FFT.

How is the phase locking value ( PLV ) used?

Phase Locking Value. Phase Locking Value (PLV) is a statistic that can be used to investigate task-induced changes in long range synchronization of neural activity from EEG data. This method is introduced in Lachaux et al., (1999). I have implemented the computation of this statistic in MATLAB and you can download it from the link below.

When to use phase locking value in EEG?

Recent Posts. Phase Locking Value (PLV) is a statistic that can be used to investigate task-induced changes in long range synchronization of neural activity from EEG data. This method is introduced in Lachaux et al., (1999).

What is the value of π In PLV metric?

A value of π indicates the peak of a crest and a –π indicates the bottom of a trough. PLV metric. Remember that there is a phase time course φ for every EEG electrode. Now consider the phase time courses of two electrodes. The difference between these two time courses (Δφ) quantifies locking between the phases of these two electrodes.

When was phase locking introduced in MATLAB Central?

This method is introduced in Lachaux et al., (1999) Human Brain Mapping. A visual summary of the method is shown in the ‘Screenshot’ file. Note that the baseline normalization procedure shown in the figure is not yet implemented in the script.