How separate are the sensory, emotional, and motivational dimensions of pain? A multidimensional scaling analysis.
To map the structure of the space generated by verbal descriptors of pain, 41 male college students made pairwise similarity judgments to all possible pairings of 16 words that describe experiences commonly associated with noxious electrical stimulation. Individual Differences Scaling (INDSCAL) yielded four dimensions (D) in the group stimulus space: D-1, Intense to Moderate Experiences, contained two attributes: Strong Sensations and Strong Emotions; D-2, Moderate to Weak Experiences, exhibited two attributes: Moderate Sensations and Moderate Emotions; D-3, Motivational State, possessed two attributes: Pain and Arousal Level; D-4, Sensory Qualities, exhibited two attributes: Pain and Somatosensory Qualities. The interpretation of the dimensions was supported by Preference Mapping (PREFMAP) and by correlations between subject weights and (a) psychological tests and (b) responses to noxious electrical stimuli.


CONCLUSIONS
semantically, the pain attribute or component of the total pain-suffering experience pervades emotional, motivational and somatosensory attributes. Pain is not an independent dimension. This means that a score on a pain rating scale is not a pure measure of the patient's pain, but is heavily influenced in unknown ways by the patient's emotional and motivational state.
Clark
W C
WC
Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA. clarkcr@pi.cpmc.columbia.edu
Janal
M N
MN
Hoben
E K
EK
Carroll
J D
JD
D000293:Adolescent; D000328:Adult; D004644:Emotions / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009042:Motivation; D010146:Pain / Q000503:physiopathology* / Q000523:psychology*; D010147:Pain Measurement; D011581:Psychological Tests; D015203:Reproducibility of Results