Psychology of Pain 299additional knowledge has been gathered since the original for-
mulation, speci“c points of posited mechanisms have been
disputed and have required revision and reformulation. Over-
all, however, the GCT has proved remarkably resilient and
”exible in the face of accumulating scienti“c data and chal-
lenges. It still provides a powerful summary of the phenomena
observed in the spinal cord and brain, and this model has the
capacity to explain many of the most mysterious and puzzling
problems encountered in the clinic. The GCT has had enor-
mous heuristic value in stimulating further research in the
basic science of pain mechanisms. The GCT can also be cred-
ited as a source of inspiration for diverse clinical applications
to control or manage pain, including neurophysiologically
based procedures (for example, neural stimulation techniques,
from peripheral nerves and collateral processes in the dorsal
columns of the spinal cord), pharmacological advances, be-
havioral treatments, and those interventions targeting modi“-
cation of attentional and perceptual processes involved in the
pain experience. After the GCT was “rst described in 1965, no
one could try to explain pain exclusively in terms of peripheral
factors.
A number of authors have extended the GCT to integrate
more detailed psychological contributions has lead to the pre-
sentation of biopsychosocial or biobehavioral models of pain
(e.g., Turk 1996; Turk & Flor, 1999). These conceptual mod-
els emphasize the important contributions, mediating, and
modulation role of a range of cognitive, affective, and behav-
ioral variables. Before describing these models, it is impor-
tant to focus on the psychology of pain.
PSYCHOLOGY OF PAIN
For the person experiencing pain, particularly chronic pain,
there is a continuing quest for relief that remains elusive and
leads to feelings of frustration, anxiety, demoralization, and
depression, compromising the quality of all aspects of their
lives. People with chronic pain confront not only the stress of
pain but also a cascade of ongoing problems (e.g., “nancial,
familial). Moreover, the experience of •medical limboŽ (i.e.,
the presence of a painful condition that eludes diagnosis and
that carries the implication of either psychiatric causation or
malingering on the one hand, or an undiagnosed potentially
disabling condition on the other) is itself the source of signif-
icant stress and can initiate psychological distress.
Biomedical factors, in the majority of cases, appear to
instigate the initial report of pain. Over time, however, psy-
chosocial and behavioral factors may serve to maintain and
exacerbate the level of pain, in”uence adjustment, and con-
tribute to excessive disability. Following from this view, pain
that persists over time should not be viewed as solely physi-
cal or solely psychological; the experience of pain is main-
tained by an interdependent set of biomedical, psychosocial,
and behavioral factors.
Consider the following scenario: A person with chronic
pain becomes inactive, leading to preoccupation with his or
her body and pain, and these cognitive-attentional changes
increase the likelihood of amplifying and distorting pain
symptoms. This person may then perceive himself or herself
as disabled. At the same time, due to fear, the pain sufferer
limits his or her opportunities to build ”exibility, endurance,
and strength without the risk of pain or injury. To the pain
sufferer, hurt is viewed as synonymous with harm. Thus, if an
activity produces an increase in pain, the sufferer terminates
the activity and avoids similar activities in the future.
Chronic pain sufferers often develop negative expectations
about their own ability to exert any control over their pain.
The negative expectations lead to feelings of frustration and
demoralization when uncontrollablepain interferes with par-
ticipation in physical and social activities.
Pain sufferers frequently terminate active efforts to man-
age pain and, instead, turn to passive coping strategies such
as inactivity, medication, or alcohol to reduce emotional
distress and pain. They also absolve themselves of personal
responsibility for managing their pain and, instead, rely on
family and health care providers. The thinking of chronic
pain patients has been shown to contribute to the exacerba-
tion, attenuation, and maintenance of pain, pain behaviors,
affective distress, adjustment to chronic pain, health care
seeking, and response to treatment (e.g., Council, Ahern,
Follick, & Cline, 1988; Flor & Turk, 1988).
In the case of chronic pain, health care providers need to
consider not only the physical basis of pain but also patients•
moods, fears, expectancies, coping resources, coping efforts,
and response of signi“cant others, including themselves.
Regardless of whether there is an identi“able physical basis
for the reported pain, psychosocial and behavioral factors in-
teract to in”uence the nature, severity, and persistence of pain
and disability. In particular, behavioral, emotional, and cog-
nitive variables should be addressed. We have already de-
scribed the important role of environmental contingencies of
reinforcement in chronic pain (e.g., Fordyce, 1976). We now
turn to the range of affective and cognitive factors that play
an equally important role.Affective FactorsPain is ultimately a subjective, private experience, but it is in-
variably described in terms of sensory and affective proper-
ties. As de“ned by the International Association for the Study