Many clinical studies of biological signals reveal correlation between the effect of estrogen, progesterone and brain signals captured in the form of Alpha, Beta, Theta and Delta by Electro Encephalography (EEG) recordings. It is known that there is significant and sustained changes in the levels of sex hormones that may have profound effect on brain functioning leading to changes in mood, memory and learning in women. The theta oscillations are involved with the memory encoding processes and anxiety; the alpha oscillations are associated with memory processing, whereas beta and delta pertain to attention. The release of the estrogen and progesterone hormones is divided into three phases that is premenstrual, menstrual and postmenstrual states. The frequency patterns of the brain signal and hormones are reported to be correlated. We have reviewed the use of EEG recordings in interpreting the variations in estrogen and progesterone level with the purpose of highlighting the area for further research. This technique can also be applied to study other biological signals, their frequencies and relative phases.

doi : 10.5214/ans.0972.7531.2009.160209

Competing interests: None.     Source of Funding: None

Received Date: 11 April 2009     Revised Date: 01 May 2009     Accepted Date: 12 May 2009