The case where monks, who had mysteriously fallen ill, are cured by reinstating their daily chanting schedule.
The story is related by the famous Christian (Episcopalian) author Rev. Doctor (PhD) Cynthia Bourgeault:
"Interestingly, this personal experience is confirmed in a now classic story told by Alfred Tomatis, the famous French eye and nose specialists (The Conscious Ear: My Life of Transformation through Listening (Tarrytown, NY: Tarrytown/Station Hill, 1992)). In a monastery in southern France some forty years ago, he was called in for a consultation because the monks had mysteriously fallen ill. Almost every kind of remedy had been tried--medication, diet, more exercise or less exercise, rest--but the malaise still lingered. Finally, searching more deeply for a cause, Tomatis discovered that not long before, the abbot had joined the modern trend of scrapping the Gregorian chant and diminishing the length of time the monks spent in chanting the Divine Office. Tomatis called for the chant to be restored, and almost instantly, the monks started to revive. It turned out that their beautiful Romanesque chapel was actually a perfectly tuned reverberating bowl, allowing the monks to receive energy--actual physical sustenance--directly from the vibrations of the chant. Removing it had left them malnourished."
Excerpted from Cynthia Bourgeault, Chanting the Psalms: A Practical Guide with Instructional CD (Boston: New Seeds Books, 2006, p.30).