Phase Locking Value (PLV) is a statistic that can be used to investigate task-induced changes in long range synchronization of neural activity. 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.
This particular implementation of estimating the PLV uses the Hilbert transform instead of wavelets.
To learn more, please read my blog entry - http://praneethnamburi.wordpress.com/2011/08/10/plv/
Kindly let me know if you have any comments/suggestions!