Classicly

Primitive Psycho-Therapy and Quackery is written by Robert Means Lawrence. Author's preface follows:

Certain historic modes of healing, including the use of medical amulets and charms, which have been regarded from early times as magical remedies, belong properly to the domain of Psychical Medicine. For the therapeutic virtues of medical amulets are not inherent in these objects, but are due to the influence exerted by them upon the imaginative faculties of the individuals who employ them.