Theta Rhythm
true
Brain waves characterized by a frequency of 4-7 Hz, usually observed in the temporal lobes when the individual is awake, but relaxed and sleepy.
https://www.ncbi.nlm.nih.gov/pubmed/3064627
http://www.case.edu/EpSO.owl#ThetaActivity
https://emedicine.medscape.com/article/1139332-overview#a1
Brain Waves