Coherence ( bottom graph image ) shows phase synchronization of left and right brain wave. In case left and right brain wave phase is synchronize then 100 % coherence, in case over 90 degree phase difference then 0 % coherence.

After version IBVA V4.9.0 application shows this phase difference more clearly than before.

Also new V4.9.5.3 application can show coherence that eliminate left first sampling, right first sampling calculation.

graph 1, 2 and 3 shows how looks like difference in coherence.

1: hiyori ( my girlfriend )

left : continuously alpha ( 6.051 micro V, 9.844 Hz ) 

right : continuously alpha ( 4.931 micro V, 11.719 Hz )  and theta (5Hz)

also can see continuously alpha coherence ( 11Hz )

comment: brain power is low however can see continuously alpha coherence line.

also right brain has two line alpha and theta is interesting.

2: Jeremy ( my friend & UFO abductee )

left : continuously alpha ( 15.657 micro V, 9.844 Hz ) 

right : continuously alpha ( 11.018 micro V, 10.312 Hz )

also can see coherence in different location

comment: nice alpha mediation at his AP.

3: masahiro in the Crop Circle

left : continuously delta and low power continuously alpha ( 12.783 micro V, 2.812 Hz ) 

right : continuously alpha ( 4.7 micro V, 10.781 Hz )

can see continuously alpha coherence and beta coherence