These can be circadian or musical
Brighter ... Other factors such as music and properly timed 
administration of the... [DOC] [TLE] Neuroscience of rhythm - Wikipedia [PAR] The neuroscience of rhythm refers to the various forms of rhythm generated by 
the central ... A great deal of these are dependent upon a certain rhythm, such as 
sleep, heart rate, ... Circadian literally translates to "about a day" in Latin.