PMS and EEG study was conducted on 6  women with PMS. The results showed that when the woman were premenstrual, their EEGs were showing slower delta activity and slower P300 evoked responses than when they were in the middle of their cycle. Slow brainwave activity is the reason for appearing PMS as a disorder.

Brainwave Frequency vs. Cerebral Blood Flow

Photic stimulation is used for effectively treating slow brainwave disorders, also beta frequency neurofeedback is used for successfully treating these disorders. Even though these treatments are speeding up the brainwaves, they seem to be of secondary importance. Cerebral blood flow increases and neuronal activity increases have greater significance.