The continuous nature of headache susceptibility

The present paper outlines a conceptual framework for understanding headache susceptibility from a psychobiological or severity perspective. The term psychobiological is intended to convey the notion that a patient's susceptibility to headache, as well as the pain experienced during headache episodes, is a continuous and multifacted condition involving cognitive, behavioral and physiological events. The term severity refers primarily to the notion that headache susceptibility and the symptoms experienced during headache attacks represent progressive conditions and that differences among headache sufferers can be understood in quantitative rather than qualitative terms. The key component of the severity model is the psychobiological predisposition which is described as a dynamic entity that is responsible for the increasing severity and chronicity of the headache sufferer's condition. This component is especially crucial for understanding headache attacks in the chronic patient which often seem to occur in the absence of specific psychological and/or physical events. Data supporting the severity approach are reviewed and the significance of these data for understanding the processes controlling chronic headache are discussed.