Disclaimers / Creds. The Role of Conditioning in Chronic Pain. Behaviorism in Pain Medicine

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1 Disclaimers / Creds The Role of Conditioning in Chronic Pain Edward C. Covington, M.D. Neurological Center for Pain Conflicts of interest I receive no income from behavioral psychologists Training Not a psychologist Many behaviorists in my training Systematic desensitization Biofeedback training Aversion therapy for smoking Pain rehabilitation program modeled on Fordyce Experience Directed a ± behaviorally based pain rehabilitation program 30+ yrs Behavioral Methods for Chronic Pain and Illness W. E. Fordyce (1976) Behaviorism in Pain Medicine A new paradigm for treating pain, other chronic medical problems Spawned operant approaches to chronic pain Exercise and adaptive behaviors reinforced Pain behaviors extinguished Seminal ideas Quota system for increasing activity Solicitous behavior as reinforcement for chronic pain Fear of movement as a barrier to improvement Behaviors associated with pain may not be intrinsic to the stimulus of pain, but may be a response to environmental reinforcers. Fordyce WE, Behavioral methods for chronic pain and illness Types of Conditioning Classical Does the name Pavlov ring a bell? Operant Skinnerian Classical Conditioning Ivan Pavlov Russian gastric physiologist Nobel Prize for digestive system research While studying digestion in dogs noted they would salivate when an assistant entered the room Discovered classical conditioning: A learning process that occurs through associations between novel and naturally occurring stimuli. Unconditioned stimulus: smell, sight of food Unconditioned response: salivation Conditioned stimulus: bell Conditioned response: salivation Extinction Repetitive ringing of bell with no associated food weakens the association and the autonomic response abates 1

2 Relevance to pain Classical Conditioning Pavlov shocked dogs paws Elicited barking and efforts to escape Shocks repeatedly paired with feeding (hungry animals) After time, the shocks elicited only salivation NO signs of discomfort IP Pavlov. 1927; Conditioned Reflexes: An Investigation of the Physiological Activity of the Cerebral Cortex. Boosting Placebo responses Colloca L et al. Pain 2008;139(2): Nocebo responses Allergic to room air Colloca L et al. Pain 2008;136: Reciprocal Inhibition Reciprocal Inhibition A response is inhibited by the occurrence of a different, incompatible response When a response antagonistic to anxiety can be elicited in the presence of anxiety-evoking stimuli, and in consequence inhibits the anxiety, the bond between these stimuli and the anxiety is weakened Reciprocal inhibition Therapy based on the inhibition of one response by conditioning an incompatible response Relaxation training paired with images of feared situation Example Cats shocked in a small cage Developed extreme aversion to it Anxiety was resistant to extinction Animals were fed in a slightly similar cage Then increasingly similar cages Ultimately feeding animals in original cage All anxiety extinguished. Integrative Psychological and Behavioral Science 1968; 3(4): Clinical Use for Pain Can Pain Be a Conditioned Response? Pavlov applied these principles to women in labor He combined education about what to expect with breathing and relaxation techniques, including gently stroking the belly. His method became the official system of obstetrical pain prevention in the USSR in Lamaze brought these ideas back from the Soviet Union Classical conditioning elicits both placebo and nocebo responses L. Colloca et al. Pain 2008;136: Keltner et al. J Neurosci 2006;26: Sound of dentist s drill? Sound has been associated with pain Strategies that mask the sound reduce pain 2

3 Drug Tolerance Conditioned Withdrawal Cues present at the time of drug taking become associated with drug effects. Drugs elicit compensatory (homeostatic) responses Compensatory responses come to be elicited by drug-paired cues. If cues are presented without the drug, the unopposed compensatory responses are evident as withdrawal Siegel S, Baptista MA, Kim JA, Exp Clin Psychopharmacol. 2000;8(3): Recovering addicts, walking through the neighborhood in which they previously bought heroin, experience piloerection, diaphoresis. Conditioned Craving A rush of craving may occur in part because the body anticipates and compensates for drug effects. A small amount of alcohol can trigger the body to prepare for a large amount When that large amount does not come, withdrawal symptoms such as nausea and fever occur. Shepard Siegel, Experimental Clinical Psychopharm 2004;12(2):3-11 Operant Conditioning PET image superimposed on MRI Cocaine users vs controls Neutral stimuli e.g., leather punch, paint brush Cocaine related stimuli e.g. drug paraphernalia Arrows indicate areas of significantly increased activity in cocaine group COCAINE USER CONTROL Neutral Cues Cocaine Cues Also called instrumental or Skinnerian conditioning Described by BF Skinner Listed as the most influential psychologist of the 20th century. Review of General Psychology, June, 2002: Contended that internal thoughts and motivations ought not be used to explain behavior. Instead, we should study only external, observable causes of behavior. Operant: any "active behavior that operates upon the environment to generate consequences" (1953). Grant S et al. PNAS 1996:93: Skinner Box Often He Used Pigeons Pellet dispenser Speaker Signal lights Lever Dispenser tube Food cup Electric grid To shock generator 3

4 Operant Conditioning the Essence Behavior consequences Subsequent behavior is a function of those consequences Behavior rewarded is behavior repeated Behaviors not reinforced are "extinguished" It has to be that way Changes often occur without awareness of subject or person who reinforces Enabling Operant Conditioning Reinforcers, by definition, increase the frequency of a behavior Positive reinforcement A reward increases the frequency of a behavior Cocaine Negative reinforcement Reducing aversive situation increases the frequency of a behavior Aspirin Shutting off pager Punishment An aversive consequence reduces the frequency of a behavior Extinction Absent reinforcement, a behavior diminishes in frequency Corollary If a behavior persists, it is being reinforced Operant Conditioning Positive reinforcement You work for the carrot Pain behavior increased by IR opioid Negative reinforcement You work to eliminate the stick LBP on going to recliner Punishment You slow down in the area where you got a speeding ticket (And speed up after) Which is more effective? Who works better The person pursuing a goal, or the person trying to avoid punishment Choosing Reinforcers You don t get far training dogs with spinach Premack Principle More probable behaviors will reinforce less probable behaviors. Premack, 1959, 1963 Example: Time in the recliner is likely to reinforce a regressed chronic pain patient Time in the gym is likely to reinforce the patient with anorexia nervosa Shaping Successive approximation An operant conditioning method for creating an entirely new behavior The organism is rewarded for each small advancement in the right direction Once one appropriate behavior is made and rewarded, the organism is not reinforced again until they make a further advancement, then another and another until the organism is only rewarded once the entire behavior is performed Much egregious behavior Began as a small transgression that was reinforced Reinforcement Schedules Continuous Reinforcement The behavior is reinforced every time it occurs. Rapid learning Extinguishes rapidly Bar Pressing Rapid learning, bar pressing Bar pressed, rewarded Steady, stable responding TIME Dispensing turned off Extinction 4

5 Reinforcement Schedules Intermittent Random Interval Reinforcement Intermittent Reinforcement The response is only reinforced part of the time. Learned behaviors are acquired more slowly The response is more resistant to extinction Fixed-ratio Response is reinforced after a specified number of responses Produces a high, steady rate of responding Break point reflects desirability of reward Hungry animal may press 10 times for 1 food pellet Some will press 800 times per injection of cocaine Variable-ratio Response is reinforced after an unpredictable number of responses. Creates a high steady rate of responding. Reward delivered unpredictably Slow learning Most resistant to extinction Bar Pressing Bar pressed, rewarded Slow learning Steady, stable responding TIME Dispensing turned off Extinction Intermittent Random Interval Reinforcement Superstitious Pigeons I don t know why this patient keeps calling all the time What do you do when he calls? Most of the time I talk him out of it. Occasionally I give him Dilaudid. Skinner rewarded pigeons every 15 sec Bizarre behaviors developed Some walked in circles One repeatedly stuck his head into the upper corner of the cage One tossed his head as if lifting a bar with it. The animals tended to repeat the behavior that had preceded the (unrelated) reward. Rain dances? If it doesn t rain, you must ve done it wrong. Operant Conditioning Key Points Often unknown to trainer or trainee Covert reinforcement of word associations Takes time, repetition Single reinforcers have less effect May explain why the role of behaviorism in chronic > acute pain Timing of Reinforcement: The Donut Principle Proximity of consequence is often more powerful (in modifying behavior) than magnitude of consequence Donuts, Buddie s Carpets, credit cards, whiskey Patients do things that make them miserable Timing is everything Recumbency Immediate pain Delayed energy, deconditioning, demineralization 5

6 Behaviorism and CNMP Fordyce hypothesis: pain behaviors are increased by reinforcers Clinical Evidence Test: reinforce only incompatible behaviors Results: debilitated patients exercised, relinquished canes, conversed re non pain related topics Application: Soon there were hundreds of PMPs, ± modeled on Fordyce s program The rapid response of severe dysfunction to environmental contingencies indirect evidence that pain behavior, dysfunction had been maintained by the environment > internal stimuli Reinforcement and Disability Post cardiotomy employment predicted by education, income, work satisfaction, energy > job exertion Rheumatoid arthritis social, work factors may effect disability > disease factors Strokes professional, managerial are most likely to return to work Most costly industrial claims undemanding and repetitive jobs, not high risk ones Prospective study of 3,020 aircraft workers, job dissatisfaction predicted back disability. Bigos SJ, et al, Spine 16, 1991 Gain / Reinforcement and Illness Review Verbal reinforcement increases performance in LBP patients Pain ratings after reinforcing well talk With repeated identical pain stimuli, intensity reports vary with feedback Studies consistently show: spouse solicitousness α pain behavior Response to behavioral programs supports the role of reinforcement But combined treatments confound interpretation Fishbain D et al: Clinical Journal of Pain, 1995 Predictors of LBP Onset 1,412 pain-free employees x 12 mo Primary care records monitored Odds of LBP Dissatisfied with work doubled Perceive income as inadequacy odds ratio 3.6 Social class IV/V odds ratio 4.8 Papageorgiou AC, et al Spine 1997 Quebec Task Force on Whiplash-Associated Disorders In BC and Saskatchewan, provinces with single-payer motor vehicle insurance, 68% and 85% of the claims paid for MVA injuries are for whiplash vs. 20% for Quebec. Explanation? No-fault system in Quebec vs tort system in Saskatchewan Spitzer W0, et al. Spine

7 Whiplash in Lithuania 202 victims, 1-3 years after rear end MVA Headache, poor concentration = controls Subjects and controls had = neck pain, associated with family history, age... 31recalled acute pain 22 recalled pain < 1 wk 2/31 recalled pain > 1 mo 0 reported persistent symptoms attributed to MVA Schrader H et al, Lancet, 1996 Whiplash in US 2/3 of all bodily injury claims Insurance Research Council Difference litigation? Criticisms: Inadequate sample size Only 31 recalled acute symptoms 95% confidence limit of a prevalence estimate of 0/31 is 10% Not very different from other countries Medicolegal attribution ignored known and unknown cultural variables Lord SM, McDonald GJ: Pain Medicine Journal Club Journal, 1997 Reinforcement Promotes Pain Behavior and Pain Perception? Patients with low back pain Known to have a solicitous spouse Noxious electrical stimulation given Reported pain intensity, measured cingulate activation by EEG The presence of the solicitous spouse increased pain intensity > doubled cingulate activation Unintended Consequences If spousal attention to pain behavior increases pain perception What is the effect if pain behavior is frequently followed by a spouse bringing oxycodone? Flor H: The functional organization of the brain in chronic pain. In Sandkahler, B. Bromm and G.F. Gebhart (Eds.) Progress in Brain Research, Vol. 129; 2000 Gain as an Impediment to Recovery Positive reinforcement Drugs, dependence, dollars Avoidance of aversive condition Imminent layoffs Intolerable work environment Abuse Exposure as inept, illiterate Disability income + insurance vs. New job without benefits Stressful job Unemployment Gain as a Prognostic Sign Meta-analysis: compensation α pain 136 comparisons: 3,802 patients 3,849 controls Pain clinic type patients Compensated patients: reduced medical / surgical treatment efficacy less education more pain Illness severity did not appear to explain, though not entirely ruled out. Rohling ML, et al: Health Psychology,

8 Gains and Losses Is the Operant Conditioning Model Still Relevant? Security Nurture Safety Stress reduction Drugs Money Gains Pride Camaraderie Identity Money Future Hope Losses There are still many behaviorally based rehabilitation programs in the US Even though many may no longer use the language, they do talk of rewarding healthy behavior, not rewarding sick-role behavior, and teaching families to do the same Their outcomes are far better than any other treatment for chronic pain Interpretation weakened by multiplicity of interventions You can t not do it Every interaction with another has the potential to reinforce or punish behavior Operant Strategies for Rehabilitation Putting It Into Practice Consistent reinforcement of well behaviors Often counter-intuitive we tend to focus attention on the person doing poorly Avoid reinforcing illness behavior Moans, gasps, etc. Reward small successes, not great efforts Distinguish help from enabling Promotes functional restoration, distraction from pain, mood normalization, quality of life Target behaviors How to Start Analyze the causes and antecedents of the behaviors and barriers to new behavior Set concrete goals Use clear reinforcement Feedback Train Families / Staff Help can be toxic Enabling Patient tends to regress Help Patient tends to progress Ignore maladaptive behaviors not maladaptive people 8

9 Significant Others Roles Friend Playmate Companion Lover Not nurse Generalization Training is useless unless the behavior is carried over in to the real world. Token economies To facilitate generalization Teach self-control techniques Change the environment Optimize naturally occurring reinforcement Family, friends and co-workers will modify behavior. If the environment does not continue to reinforce wellness It will extinguish Optimize Naturally Occurring Reinforcement Rest Attention Money Fun Companionship Sex As much as possible, contingent on wellness behavior Philosophical Questions Does operant conditioning change judgment? If every rx for Valium elicits praise and gratitude, and every refusal takes longer and elicits the opposite Does it change my opinion of the indications for Valium? Private practice psychiatry Endogenous depression vs marital discord 4.5 x compensation, no effort, hassle Meta-analysis What do we do when the extant contingences fail to reinforce operant conditioning treatment and instead reinforce interventions? Was Freud an Inadvertent Behaviorist? Pain Behavior All his patients talked about sex and their mothers Mine don t Why? A function of Internal drive External contingencies Neither is easily quantifiable 9

10 The Question of Gain How are we to understand the complaints and other pain behaviors of our patients? A response to suffering? A quest for reward? Dilemma Pain assessment is necessary to determine diagnosis to select treatment to rate impairment / disability Pain is not demonstrable on exam visible on imaging reflected in chemistries Behavior is the only way we have to assess it Pain Behavior Suffering Pain The Problem We must assess the organic state of the patient with respect to pain Our primary guide is behavior Nociception Behavior can be unreliable John Loeser Pain is Just What the Patient Says It Is Politically useful Clinically appropriate at times, especially Acute pain Cancer pain Scientifically tenable ONLY in the absence of incentives to minimize or exaggerate Pain complaints, like other behaviors, are modified by environmental contingencies Countertransference (a term no real behaviorist would use) We are trained to extend ourselves for those who are suffering Suspicion the person is exaggerating for gain Resentment that the patient has it easy Feeling victimized by the patient I m paying his rent. Clinician s response Betrayal Rage 10

11 Combatting Negative Countertransference Ask yourself Would the patient have desired to be in this situation when he grew up? Would I trade life circumstances with him? What is his quality of life? His future? Is he happy? Steer between enabling and rejection Fordyce Legacy Led to hundreds of behaviorally based pain rehabilitation programs Most of which were extinguished Because they weren t reinforced The ultimate confirmation Fordyce Legacy Less pessimistically It s become part of the fabric of what we do Based on conversations with clinicians in pain rehabilitation programs Most train staff / families to reinforce wellness behavior Most try not to attend too much to pain behavior Most never mention the words Operant Skinner Fordyce Fordyce Legacy Existing programs Cleveland Clinic Chronic Pain Rehabilitation Program Heavily behaviorally based Lots of talk about ignoring sick role behaviors, rewarding the converse Mayo Clinic It s the foundation of our program We use that language with all the students. Dr Cynthia Townsend RIC Systematic desensitization is part of treatment Families taught to reward healthy behavior Non-psychologists may think less in operant terms Dr Karen Feldman Conclusion We re still doing it; we re being reinforced Maybe its random intermittent reinforcement and we just can t stop 11