Rationale and methods for assessment of pain-depressed behavior in preclinical assays of pain and analgesia.

Pain-depressed behavior can be defined as any behavior that decreases in rate, frequency, duration, or intensity in response to a putative pain state. Common examples include pain-related decreases in feeding, locomotion and expression of positively reinforced operant behavior. In humans, depression of behavior is often accompanied by a comorbid depression… (More)