theta rhythm: the normal brainwave in the encephalogram of a person who is awake but relaxed and drowsy; occurs with low frequency and low amplitude
brainwave: (neurophysiology) rapid fluctuations of voltage between parts of the cerebral cortex that are detectable with an electroencephalograph
devil's tongue: foul-smelling somewhat fleshy tropical plant of southeastern Asia cultivated for its edible corms or in the greenhouse for its large leaves and showy dark red spathe surrounding a large spadix