Associative learning mechanisms may trigger increased burden of chronic pain; unlearning and extinguishing learned maladaptive responses should help chronic pain patients
-
Harald Breivik
In this issue of the Scandinavian Journal of Pain Daniel S. Harvie and co-workers with G. Lorimer Moseley as senior author, publish interesting and potentially clinically important results from a study on volunteers [1]. Visual and auditory cues are known to enhance pain perception both in laboratory and in clinical scenarios, effects that are due to expectation of impending harm. In this study, Harvie and co-workers were able to show that somatosensory cues (vibrotactile stimuli) also can modulate pain perception. The brief (milliseconds) conditioning stimulus close to the nociceptive stimulus could not allow any conscious expectation of effect. They therefore consider their findings due to an associative learning mechanism, learning that can occur without conscious evaluation of the conditioning stimulus [1]. They propose that this has implications for development of chronic pain conditions and for treatment of pain.
1 Associative learning and perception of pain from nociceptive stimuli
Associative learning mechanisms are different from those mechanisms that link increased pain perception to pain-related fear and avoidance [1,2]. They studied, in healthy volunteers, pain- modifying effects by vibrotactile stimuli near the location on the forearm where they induced pain by electrical stimuli to create pain-intensity between 2/10 and 8/10 on a NRS-11 scale. They found significantly higher perceived pain-intensity of an electrically induced pain when this was paired with the vibrotactile cues. Thus, in this classical conditioning study they were able to document that a non-nociceptive somatosensory input can increase the perceived pain-intensity of a painful stimulus, in the pain- laboratory [1].
2 Clinical implication of associative learning that increase the experience of pain of a nociceptive stimulus
For a clinician, the changes in perceived pain due to the vibro- tactile conditioning stimulus were tiny: from 48.6 to 51.2 mm on a 150 mm visual analogue scale for pain intensity (VAS). The mean difference was 3 mm (CI 95% 0.4–4.8 mm). The authors admit that this may not be considered a dramatic effect, but the fact that they can document such an effect in the artificial context of a pain lab-oratory, may indicate that in a therapeutic context these effects could be larger and should be studied, and hopefully they can be exploited in the clinic [1].
They emphasize that based on their findings; it must be worthwhile in clinical research to explore associative learning mechanisms during development of a chronic pain condition. With more knowledge of such associative learning mechanisms, unlearning techniques aiming to extinguish these associations could be a new principle for treating chronic pain conditions. This is very welcome because we are not always treating successfully chronic pain, such as complex regional pain syndrome (CRPS) [3].
3 Unlearning complex and poorly understood maladaptive mechanisms in complex regional pain syndrome - CRPS
Data indicating that a neuroinflammation may be behind the early phases of a developing CRPS [4,5,6]. In fact, we do not fully understand the mechanisms, in the “black box”, our CNS, that can lead to such a horrendous pain experiences with subsequent pathophysiological, mental, and socioeconomic changes [3]. Because we do not understand fully the mechanisms operating in the “black box”, we are not always able to stop and reverse this decline into an existence with very low quality of life [3].
Psychological factors do not start a CRPS-condition, but once established the healing process of a CRPS can be delayed by psychological “complications” [7]. We clearly need expert pain- psychologists in the team trying to help patients with such complex pain conditions as a CRPS. The positive effects of graded motor imagery and mirror therapy [8,9,10], exposure therapy [11], and patient education [12], all come from distinguished experimental and clinical psychologists [1].
Being aware of the fact that associative learning can contribute to the complexities of chronic pain conditions, and taking this into our understanding and treatment of our unfortunate chronic pain patients, will be of value as we strive to help our patients [1].
DOI of refers to article: http://dx.doi.org/10.1016/j.sjpain.2015.09.007.
-
Conflicts of interest: None declared.
References
[1] Harvie DS, Meulders A, Madden VJ, Hillier SL, Peto DK, Brinkworth R, Moseley GL. When touch predicts pain: predictive tactile cues modulate perceived intensity of painful stimulation independent of expectancy. Scand J Pain 2016;11:11-8.Search in Google Scholar
[2] Vlaeyen JW, Linton SJ. Fear-avoidance and its consequences in chronic musculoskeletal pain: astate of the art. Pain 2000;85:317-32.Search in Google Scholar
[3] Bruehl S. Complex regional pain syndrome. Br Med J 2015;350:h2730.Search in Google Scholar
[4] Birklein F, Schlereth T. Complex regional pain syndrome—significant progress in understanding. Pain 2015;156:S94-103.Search in Google Scholar
[5] Birklein F, O’Neill D, Schlereth T. Complex regional pain syndrome: an optimistic perspective. Neurology 2015;84:89-96, http://dx.doi.org/10.1212/WNL.0000000000001095.Search in Google Scholar
[6] Moseley GL, O’Connell NE. Finding the balance in complex regional pain syndrome: expertise, optimism, and evidence. Neurology 2015;84:19-20, http://dx.doi.org/10.1212/WNL.0000000000001114.Search in Google Scholar
[7] Beana DJ, Johnson MH, Heiss-Dunlop W, Leed AC, Kydd RR. Do psychological factors influence recovery from complex regional pain syndrome type 1? A prospective study. Pain 2015;156:2310-8.Search in Google Scholar
[8] Moseley GL. Graded motor imagery is effective for long-standing complex regional pain syndrome: a randomised controlled trial. Pain 2004;108:192-8.Search in Google Scholar
[9] Moseley GL, Butler DS, Beames TB, Giles TJ. The graded motor imagery handbook. Adelaide: Noigroup Publications; 2012.Search in Google Scholar
[10] Sayegh SA, Filen T, Johansson M, Sandstrom S, Stiewe G, Butler S. Mirror therapy for Complex Regional Pain Syndrome (CRPS)—a literature review and an illustrative case report. Scand J Pain 2013;4:200-7, http://dx.doi.org/10.1016Zj.sjpain.2013.06.002.Search in Google Scholar
[11] Vlaeyen JW, de Jong J, Geilen M, Heuts PH, van Breukelen G. Graded exposure in vivo in the treatment of pain-related fear: a replicated single-case experimental design in four patients with chronic low back pain. Behav Res Ther 2001;39:151-66.Search in Google Scholar
[12] Moseley GL, Nicholas MK, Hodges PW. A randomized controlled trial of intensive neurophysiology education in chronic low back pain. Clin J Pain 2004;20:324-30.Search in Google Scholar
© 2015 Scandinavian Association for the Study of Pain
Articles in the same Issue
- Editorial comment
- Psychophysiological effects of threatening a rubber hand that is perceptually embodied in healthy human subjects
- Original experimental
- A preliminary investigation into psychophysiological effects of threatening a perceptually embodied rubber hand in healthy human participants
- Editorial comment
- Analysis of C-reactive protein (CRP) levels in pain patients – Can biomarker studies lead to better understanding of the pathophysiology of pain?
- Clinical pain research
- Serum C-reactive protein levels predict regional brain responses to noxious cold stimulation of the hand in chronic whiplash associated disorders
- Editorial comment
- Importance of early diagnosis of complex regional pain syndrome (CRPS-1 and CRPS-2): Delayed diagnosis of CRPS is a major problem
- Clinical pain research
- Delayed diagnosis and worsening of pain following orthopedic surgery in patients with complex regional pain syndrome (CRPS)
- Editorial comment
- Associative learning mechanisms may trigger increased burden of chronic pain; unlearning and extinguishing learned maladaptive responses should help chronic pain patients
- Original experimental
- When touch predicts pain: predictive tactile cues modulate perceived intensity of painful stimulation independent of expectancy
- Editorial comment
- Low back pain among nurses: Common cause of lost days at work and contributing to the worldwide shortage of nurses
- Observational study
- Pain-related factors associated with lost work days in nurses with low back pain: A cross-sectional study
- Editorial comment
- Assessment of persistent pelvic pain after hysterectomy: Neuropathic or nociceptive?
- Clinical pain research
- Characterization of persistent pain after hysterectomy based on gynaecological and sensory examination
- Editorial comment
- Transmucosal fentanyl for severe cancer pain: Nasal mucosa superior to oral mucosa?
- Original experimental
- Facilitation of accurate and effective radiation therapy using fentanyl pectin nasal spray (FPNS) to reduce incidental breakthrough pain due to procedure positioning
- Editorial comment
- Why do we have opioid-receptors in peripheral tissues? Not for relief of pain by opioids
- Clinical pain research
- Peripheral morphine reduces acute pain in inflamed tissue after third molar extraction: A double-blind, randomized, active-controlled clinical trial
- Editorial comment
- Chronic pain and psychological distress among long-term social assistance recipients – An intolerable burden on those on the lowest steps of the socioeconomic ladder
- Clinical pain research
- The co-occurrence of chronic pain and psychological distress and its associations with salient socio-demographic characteristics among long-term social assistance recipients in Norway
- Editorial comment
- Fifty years on the Visual Analogue Scale (VAS) for pain-intensity is still good for acute pain. But multidimensional assessment is needed for chronic pain
- Clinical pain research
- Patient reported outcome measures of pain intensity: Do they tell us what we need to know?
- Editorial comment
- Postoperative pain documentation 30 years after
- Topical review
- Postoperative pain documentation in a hospital setting: A topical review
- Editorial comment
- Aspects of pain attitudes and pain beliefs in children: Clinical importance and validity
- Observational study
- The Survey of Pain Attitudes: A revised version of its pediatric form
- Editorial comment
- The role of social anxiety in chronic pain and the return-to-work process
- Clinical pain research
- Social Anxiety, Pain Catastrophizing and Return-To-Work Self-Efficacy in chronic pain: a cross-sectional study
- Editorial comment
- Advances in understanding and treatment of opioid-induced-bowel-dysfunction, opioid-induced-constipation in particular Nordic recommendations based on multi-specialist input
- Topical review
- Definition, diagnosis and treatment strategies for opioid-induced bowel dysfunction–Recommendations of the Nordic Working Group
- Observational study
- Opioid-induced constipation, use of laxatives, and health-related quality of life
- Editorial comment
- Migraine headache and bipolar disorders: Common comorbidities
- Systematic review
- Migraine headache and bipolar disorder comorbidity: A systematic review of the literature and clinical implications
- Editorial comment
- The role of catastrophizing in the pain–depression relationship
- Clinical pain research
- The mediating role of catastrophizing in the relationship between pain intensity and depressed mood in older adults with persistent pain: A longitudinal analysis
- Announcement
- May 26-27, 2016 Scandinavian Association for the Study of Pain, Reykjavik, Iceland May 25, 2016 PhD course
Articles in the same Issue
- Editorial comment
- Psychophysiological effects of threatening a rubber hand that is perceptually embodied in healthy human subjects
- Original experimental
- A preliminary investigation into psychophysiological effects of threatening a perceptually embodied rubber hand in healthy human participants
- Editorial comment
- Analysis of C-reactive protein (CRP) levels in pain patients – Can biomarker studies lead to better understanding of the pathophysiology of pain?
- Clinical pain research
- Serum C-reactive protein levels predict regional brain responses to noxious cold stimulation of the hand in chronic whiplash associated disorders
- Editorial comment
- Importance of early diagnosis of complex regional pain syndrome (CRPS-1 and CRPS-2): Delayed diagnosis of CRPS is a major problem
- Clinical pain research
- Delayed diagnosis and worsening of pain following orthopedic surgery in patients with complex regional pain syndrome (CRPS)
- Editorial comment
- Associative learning mechanisms may trigger increased burden of chronic pain; unlearning and extinguishing learned maladaptive responses should help chronic pain patients
- Original experimental
- When touch predicts pain: predictive tactile cues modulate perceived intensity of painful stimulation independent of expectancy
- Editorial comment
- Low back pain among nurses: Common cause of lost days at work and contributing to the worldwide shortage of nurses
- Observational study
- Pain-related factors associated with lost work days in nurses with low back pain: A cross-sectional study
- Editorial comment
- Assessment of persistent pelvic pain after hysterectomy: Neuropathic or nociceptive?
- Clinical pain research
- Characterization of persistent pain after hysterectomy based on gynaecological and sensory examination
- Editorial comment
- Transmucosal fentanyl for severe cancer pain: Nasal mucosa superior to oral mucosa?
- Original experimental
- Facilitation of accurate and effective radiation therapy using fentanyl pectin nasal spray (FPNS) to reduce incidental breakthrough pain due to procedure positioning
- Editorial comment
- Why do we have opioid-receptors in peripheral tissues? Not for relief of pain by opioids
- Clinical pain research
- Peripheral morphine reduces acute pain in inflamed tissue after third molar extraction: A double-blind, randomized, active-controlled clinical trial
- Editorial comment
- Chronic pain and psychological distress among long-term social assistance recipients – An intolerable burden on those on the lowest steps of the socioeconomic ladder
- Clinical pain research
- The co-occurrence of chronic pain and psychological distress and its associations with salient socio-demographic characteristics among long-term social assistance recipients in Norway
- Editorial comment
- Fifty years on the Visual Analogue Scale (VAS) for pain-intensity is still good for acute pain. But multidimensional assessment is needed for chronic pain
- Clinical pain research
- Patient reported outcome measures of pain intensity: Do they tell us what we need to know?
- Editorial comment
- Postoperative pain documentation 30 years after
- Topical review
- Postoperative pain documentation in a hospital setting: A topical review
- Editorial comment
- Aspects of pain attitudes and pain beliefs in children: Clinical importance and validity
- Observational study
- The Survey of Pain Attitudes: A revised version of its pediatric form
- Editorial comment
- The role of social anxiety in chronic pain and the return-to-work process
- Clinical pain research
- Social Anxiety, Pain Catastrophizing and Return-To-Work Self-Efficacy in chronic pain: a cross-sectional study
- Editorial comment
- Advances in understanding and treatment of opioid-induced-bowel-dysfunction, opioid-induced-constipation in particular Nordic recommendations based on multi-specialist input
- Topical review
- Definition, diagnosis and treatment strategies for opioid-induced bowel dysfunction–Recommendations of the Nordic Working Group
- Observational study
- Opioid-induced constipation, use of laxatives, and health-related quality of life
- Editorial comment
- Migraine headache and bipolar disorders: Common comorbidities
- Systematic review
- Migraine headache and bipolar disorder comorbidity: A systematic review of the literature and clinical implications
- Editorial comment
- The role of catastrophizing in the pain–depression relationship
- Clinical pain research
- The mediating role of catastrophizing in the relationship between pain intensity and depressed mood in older adults with persistent pain: A longitudinal analysis
- Announcement
- May 26-27, 2016 Scandinavian Association for the Study of Pain, Reykjavik, Iceland May 25, 2016 PhD course
