Stéphanie Volders

Fear reduction in patients with chronic pain: a learning theory perspective.

Acute pain informs the individual that there is an imminent threat of body damage, and is associated with the urge to escape and avoid. Fear learning takes place when neutral stimuli receive the propensity to predict the occurrence of pain, and when defensive responses are initiated in anticipation of potential threats to the integrity of the body. Fear-avoidance models have been put forward featuring the role of individual differences in catastrophic interpretations of pain in the modulation of learning and avoidance. Based on extensive literature on fear reduction in anxiety disorders; cognitive–behavioral treatments have been developed and applied to patients with chronic pain reporting substantial pain-related fear. In this article, we discuss mechanisms underlying the acquisition, the assessment and extinction of pain-related fear through the cognitive–behavioral treatment of pain-related fear. Finally, we provide a number of critical notes and directions for future research in the field of chronic pain and pain-related fear.

Relationship between different measures of pain-related fear and physical capacity of the spine in patients with chronic low back pain

BACKGROUND CONTEXT It has been controversially stated that pain-related fear is a more important determining factor for disability in chronic low back pain (CLBP) than pain or physical impairment in itself. So far, the relationship between psychological and physiological determinants of chronic pain, that is, pain-related fear and physiological abilities, remains unclear. PURPOSE To evaluate whether pain-related fear assessed by different tools (both task specific and non task specific) is related to physical capacity measured by specific spine tests and, secondarily, to explore the relationship between different pain-related fear assessment tools. STUDY DESIGN/SETTING Cross-sectional study. PATIENT SAMPLE Fifty patients with CLBP (50% women; meanage [standard deviationage]: 44.2 [9.5 years]). OUTCOME MEASURES Physical capacity by means of three specific spine tests, that is, the finger-floor distance test (flexibility), a maximal isometric strength test of trunk extensor muscles (strength), and the Sorensen test (endurance). Pain-related fear by means of self-report measures, that is, the Tampa Scale for Kinesiophobia (TSK), the Photograph Series of Daily Activities (PHODA), and a fear visual analog scale (FVAS) tailored to the spine tests. METHODS Participants were asked to complete the TSK and PHODA and to perform the three spine tests. Right before performing each of the spine tests, an FVAS was filled out. Linear regression analyses controlling for gender and age were performed to study the association between the pain-related fear measurements and the results of the spine tests. To investigate the relationship between the pain-related fear measurements, correlation tests were performed. RESULTS The linear regression analyses revealed that neither the TSK and PHODA scores nor the FVAS scores were significantly related to the physical capacity measurements. The correlational tests showed no significant correlation between the PHODA, TSK, and FVAS scores. CONCLUSIONS The present study shows that neither the task-specific tool (FVAS) nor the non task-specific questionnaires (TSK and PHODA) were significantly correlated to the spine tests in patients with CLBP. This is contrary to earlier evidence according to which physical capacity is inversely related to the level of pain-related fear, and it suggests that one should not draw conclusions about physical capacity based on pain-related fear scores. Furthermore, the different assessment tools for pain-related fear were surprisingly not correlated with each other.

Safety behavior can hamper the extinction of fear of movement-related pain: an experimental investigation in healthy participants.

Excessive fear of movement-related pain (FMRP), and its associated avoidance behavior, is considered a major risk factor for disability in chronic musculoskeletal pain. The current study aimed to investigate whether engaging in safety behavior, conceptualized as an avoidance response, hampers the extinction of FMRP. In a differential conditioning paradigm, we used joystick movements as conditioned stimuli (CSs) and a painful electrocutaneous stimulus as the unconditioned stimulus (US). In the Safety group, participants received the opportunity to avoid the pain-US by pressing a safety button during the extinction phase, whereas in the Control group, this option was not included. In a subsequent test phase, this safety button was no longer available. In two experiments, results demonstrate successful acquisition and extinction. Retrospective FMRP ratings in both experiments revealed a return of fear of pain in the test phase in the Safety group, but not in the Control group. In Experiment 1, mean eyeblink startle reflex amplitudes partly corroborated the self-report findings on fear of pain. The present results suggest that performing safety behavior during cognitive-behavioral interventions, i.e., exposure, might increase the risk of a return of FMRP.

Avoidance behavior in chronic pain research: A cold case revisited

In chronic musculoskeletal pain, avoidance behavior is a prominent behavioral characteristic that can manifest itself in various ways. It is also considered a crucial component in the development and maintenance of chronic pain-related disability, supposedly fueled by pain-related fear and catastrophic beliefs. Despite the frequent occurrence of avoidance behavior and its potential impact on quality of life, relatively little research has been dedicated to the nature of avoidance in chronic pain and its assessment, leaving its underlying mechanisms poorly understood. In the current paper, we stipulate some of the existing parallels between chronic pain research and more basic fear and anxiety research inspired by modern learning theories. After a brief introduction, we discuss avoidance theories that are likely apt to be applied to chronic pain, including avoidance as a response that can affect fear responding, and the role of avoidant decision making and motivational context. Finally, we will outline how these theories may impact clinical treatment.

The Reduction of Fear of Movement-related Pain: Does Motivational Context Matter?

Objectives:Previous research indicates that reducing fear of movement-related pain is hampered by engaging in safety-seeking behavior. We tested the hypothesis that fear reduction is only disrupted by behavior that serves a pain-avoidance goal (safety-seeking), but not when it is serving an achievement goal. Methods:Using the voluntary joystick movement paradigm, fear of a painful joystick arm movement was successfully acquired by repeatedly pairing this joystick movement with a painful electrocutaneous stimulus (unconditioned stimulus [pain-US]) and this fear was subsequently extinguished using a Pavlovian extinction procedure. During extinction, a Safety group and Reward group both pressed a safety button, whereas a third Control group did not. Results:Pain-US expectancy and fear of movement-related pain ratings show a gradual fear reduction in the Control Group, but a return of fear when the button is pressed to avoid the pain-US (Safety group). When the same button is used to attain a reward (Reward group), subsequent return of fear is attenuated. In addition, we investigated the reliability of the return of fear in the Safety group and Reward group, using a customized Reliable Change Index. This index confirms that the return of fear was only reliable in the Safety group, and that this return of fear is associated with more perceived control over the nonoccurrence of the pain-US when pressing the button. Discussion:These results highlight the importance of motivational context in understanding the role of safety-seeking behavior in exposure-based therapies.

Sub-optimal presentation of painful facial expressions enhances readiness for action and pain perception following electrocutaneous stimulation

Observation of others’ painful facial expressions has been shown to facilitate behavioral response tendencies and to increase pain perception in the observer. However, in previous studies, expressions were clearly visible to the observer and none of those studies investigated the effect of presence of peripheral stimulation on response tendencies. This study focuses on the effect of sub-optimal presentation of painful facial expressions in the presence and absence of an electrocutaneous stimulus. Twenty-two healthy individuals categorized arrow targets which were preceded by a sub-optimally presented facial expression (painful, happy, or neutral in different blocks). On half of the trials, aversive electrocutaneous stimulation was delivered to the wrist of the non-dominant hand between the presentation of facial expression and target (an arrow directing to right or left). Participants’ task was to indicate direction of the arrow as soon as it appears on the screen by pressing the corresponding key on the keyboard and to rate their pain at the end of block. Analysis showed that responses were faster to targets preceded by aversive stimulation than to targets not preceded by stimulation, especially following painful expressions. Painfulness ratings were higher following painful expressions than following happy expressions. These findings suggest that sub-optimally presented painful expressions can enhance readiness to act to neutral, non-pain-related targets after aversive stimulation and can increase pain perception.

990 PAIN-RELATED FEAR AND CHRONIC PAIN: INTEROCEPTIVE FEAR CONDITIONING AS A NOVEL APPROACH

Results: In the multivariate context, depression, anxiety, catastrophizing, and disability were intercorrelated. Self-efficacy correlated positively with variables of quality of life and general health. These two groups of variables were negatively correlated. The pain variables – duration of pain, pain intensity, and spreading of pain – formed a third group of variables. Self-efficacy function was negatively correlated to these three pain variables. When regressing disability, quality of life, and health, we found that selfefficacy had a positive impact whereas symptoms, catastrophizing, and pain had a negative influence on these aspects. Different patterns of influencing variables were discerned for the three different analyses, and specific patterns of the subscales of selfefficacy corresponded to specific patterns of negative factors for the outcome of disability, quality of life, and health. Conclusion: There is a complex interaction of psychological factors and symptoms and their positive and negative influence on disability, quality of life, and health. The results indicate that it might be important to assess and influence both enhancing and detoriating factors to ensure an effective pain management programme.