Handbook of Psychology

Unidimensional Conceptualizations of Chronic Pain 295

Assessment based on the psychogenic perspective is di-
rected toward identifying the personality factors or psy-
chopathological tendencies that instigate and maintain the
reported pain. Traditional psychological measures such as the
Minnesota Multiphasic Personality Inventory (MMPI) and
the Symptom Checklist-90 (SCL90) are commonly used to
evaluate chronic pain patients (Piotrowski, 1997). High
scores in these instruments are considered to support the no-
tion of psychogenic pain. It is assumed that reports of pain
will cease once the psychological problems are managed.
Treatment is geared toward helping the patient gain insight
into the underlying maladaptive, predisposing psychological
factors (e.g., Beutler, Engle, Oro•-Beutler, Daldrup, &
Meredith 1986; Grzesiak, Ury, & Dworkin, 1996).
Although the psychogenic pain notion is ubiquitous, em-
pirical evidence supporting it is scarce. A substantial number
of chronic pain patients do not exhibit signi“cant psy-
chopathology. Moreover, studies suggest that in the majority
of cases the emotional distress observed in these patients
occurs in response to persistence of pain and not as a causal
agent (e.g., Okifuji, Turk, & Sherman, 2000; Rudy, Kerns, &
Turk, 1988) and may resolve once pain is adequately treated
(Wallis, Lord, & Bogduk, 1997). Not surprisingly, insight-
oriented therapy has not been shown to be effective in reduc-
ing symptoms for the majority of patients with chronic pain.
There are, however, some patients for whom such insight is
essential before they are able to engage successfully in reha-
bilitation (Grzesiak et al., 1996).

Secondary-Gain Model of Chronic Pain

The secondary-gain model is an alternative to the psy-
chogenic model. From this perspective, reports of pain in the
absence of or in excess of physical pathology are attributed
to the desire of the patient to obtain some bene“t such as
attention, time off from undesirable activities, or “nancial
compensation„ secondary gains.In contrast to the psy-
chogenic model, in the secondary-gain view, the assumption
is that the patient is consciouslyattempting to acquire a de-
sirable outcome. Simply put, the report of pain in the absence
of a pathological process is regarded as fraudulent (Bayer,
1984).
Assessment of patients from the secondary-gain model fo-
cuses on identifying discrepancies between what patients say
they are capable of doing and what they actually can do or
from facial expressions that deviate from norm-based expec-
tations (Craig, Hyde, & Patrick, 1991). A high degree of dis-
crepancy between what patients say about their pain and
physical capacity and performance on more objective assess-
ment of physical functioning and facial expressions are

believed to be evidence that patients are exaggerating or fab-

ricating their symptoms to obtain a desired outcome. Thus,

repeated performance of functional capacity testing that iden-

ti“es discrepancies (sometimes referred to as the index of

congruence) in performance has been used to label patients

as symptom magni“ers at best or malingerers at worst. Sur-

veillance is also used, again seeking discrepancies between

the patient•s reports of activity and objective performance.

Thus, a patient who states that he cannot lift weights over

10 pounds might and who refuses to attempt to lift during a

functional capacity evaluation might be observed or even

videotaped lifting groceries out of his car. The ability to lift

the bags of groceries is taken as evidence that the patient is

capable of lifting. Thus, the report of the inability to lift, in

light of the lifting of groceries, is viewed as proof of dissim-

ulation. Inconsistency in reported ability and actual perfor-

mance fails to consider the limited ability of people to

accurately estimate the capacity and the refusal to perform

associated with fear of injury, reinjury, or exacerbation of

pain (e.g., Lenthem, Slade, Troup, & Bentley, 1983; Vlaeyen,

Kole-Snijders, Boeren, & van Eek, 1995).

The treatment of pain from the secondary-gain perspec-

tive is simple, denial of disability payments. The assumption

being that denial of disability will lead inevitably to prompt

resolution of the reported symptoms. Although this view is

prevalent, especially among third-party payers, there is little

evidence of dramatic cure of pain following denial of

disability.

Behavioral Conceptualizations

Pain is an unavoidable part of human life. No learning is re-

quired to activate nociceptive receptors. However, pain is a

potent and salient experience for all sentient organisms (ani-

mals including humans). Beyond mere re”exive actions, all

must learn to avoid, modify, or cope with noxious stimula-

tion. There are three major principles of behavioral learning

that help us understand acquisition of adaptive as well as dys-

functional behaviors associated with pain.

Classical (Respondent) Conditioning

In his classic experiment, Pavlov found that a dog could be

taught, or conditioned,to salivate at the sound of a bell by

pairing the sound with food presented to a hungry dog. Sali-

vation of dogs in response to food is natural; however, by pre-

ceding the feeding with the sound of a bell, Pavlov•s dogs

learned to associate the sound of the bell with an imminent

feeding. Once this association was learned, or conditioned,

the dogs were found to salivate at the mere sound of a bell