ABSTRACT
By definition, pain is a noxious sensation that evokes perceptions of dysphoria and illness. The linkage of sensory phenomena with cognitive processes is important to the strong avoidant motor reflexes, autonomic events, and emotional responses that are co-terminal with both the pain experience and its expectation (Cazzullo & Gala, 1987). The scientific perspective has evolved to characterize pain as a heterogeneous entity that may be classified by temporal (i.e., acute, chronic), mechanistic (i.e., nociceptive, inflammatory, neuropathic), and phenomenologic (i.e., eudynia, maldynia) factors. Far from being mutually exclusive, these classifications are both overlapping and interactive and can be useful when elucidating the qualitative, quantitative, and pathologic variables that contribute to a particular clinical pain syndrome (Woolf & Max, 2001). The neural substrates that are involved in processing noxious input contribute to both the sensation and cognitive–emotional phenomena of pain.
