The authors describe five patients to demonstrate the polymorphous determinants of certain factors in headache—factors intermediate between the genetic causes and the overt syndrome. The function of the head in the birth canal conditions the engram for future anxieties, such as castration anxiety. In the latency period the rarity of headaches is explained as resulting from the child's acceptance of castration (celibacy), and also from its need for active sublimations in this period. In premenstrual headaches the greatest intensity occurs when the displacement fails and the menstrual discharge has to be accepted; relief of the pain follows this acceptance.