Role of the Higher Central Nervous System in Nociceptive Pain

The term perception, when applied to pain, refers to the awareness of a noxious sensation, appreciation of negative emotions, interpretation, and attribution of meaning to the experience. While patients are surprisingly uniform in their perception of pain, they differ greatly in their reaction to it. Attention and cognition, along with cultural, emotional, and motivational differences, will alter or modulate the patient’s response to pain.

Attention is largely under conscious control. The patient experiencing pain has a choice: attend to the noxious sensations or attend to signals that can exclude pain perception from conscious awareness. For example, most hypnotic procedures involve the redirection of attention away from pain; breathing exercises use attentional control to suppress the pain of natural childbirth; and music used during dental procedures requires that the patient concentrate on the music.

Cognition involves memory, discrimination, and judgment, i.e., matching the present situation against past experiences and attributing meaning to the current problem. Cognition differs from patient-to-patient and even within the same patient at different times if the thought processes associated with the experience are different. Ultimately, patients will respond to pain congruent with their cultural heritage and its social consequences.