Humming: A Vocal Standard with a Diurnal Variation

Science  10 Nov 1961:
Vol. 134, Issue 3489, pp. 1519-1520
DOI: 10.1126/science.134.3489.1519


The process of humming can be used as a basal vocal measurement which can be repeatedly obtained with an accuracy comparable to that of other physiological variables. Studies have shown a diurnal fluctuation of the hum frequency. Data were collected by employing automatic telephone-answering equipment.