PLV：这里举两点说明，如上图所示 两个红点 电极

PLI:Phase lag index

PLI is much less affected by the influence of common sources (volume conduction) and active reference electrodes.

PLI=|sign(P1-P2)|

0 代表 没有相位差或者相位差为0

1 代表代表相位差稳定

A PLI of zero indicates either no coupling or coupling with a phase difference centered around 0 mod π. A PLI of 1 indicates perfect phase locking at a value of Φ different from 0 mod π. The stronger this nonzero phase locking, the larger will PLI be. Note that PLI does no longer indicate which of the two signals is leading in phase. Whenever needed, however, this information can be easily recovered, for instance, by omitting the absolute value in the expression above.

PLI越大，说明的 phase locking 越大