In the Classification of Headache developed by the select committee of the National Institutes of Health in 1962, the following definitions are given1:
VASCULAR HEADACHES OF THE MIGRAINE TYPE
These consist of recurrent attacks of headache, widely varied in intensity, frequency, and duration. The attacks are commonly unilateral in onset, are usually associated with anorexia and sometimes nausea and vomiting, in some are preceded by or associated with conspicuous sensory, motor, and mood disturbances; they are often familial.Evidence supports the view that cranial arterial distention and dilatation are importantly implicated in the painful phase, but cause no permanent changes in the involved vessel. The following are particular varieties of headache, each sharing some but not necessarily all the previously mentioned features: "Classic" migraine, is a vascular headache with sharply defined, transient visual or other sensory and/or motor prodromes. "Common" migraine, is a vascular headache without striking prodromes and