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European Journal of Pain (London,... Nov 2022The mechanisms of pain perception in individuals with masochistic behaviour (MB) remain poorly documented. We hypothesized that MB is associated with context-specific...
BACKGROUND
The mechanisms of pain perception in individuals with masochistic behaviour (MB) remain poorly documented. We hypothesized that MB is associated with context-specific changes in descending pain modulation.
METHODS
We compared the effects of four standardized sets of images with positive (erotic), negative (mutilations), masochistic or neutral emotional valences on the RIII nociceptive reflex evoked by electrical stimulation of the sural nerve and recorded on the ipsilateral biceps femoris in 15 controls and 15 men routinely engaging in MB. We systematically assessed the RIII reflex threshold and recruitment curves (up to the tolerance threshold), thermal (heat and cold) pain thresholds measured on the upper and lower limbs and responses to the pain sensitivity questionnaire, to compare basal pain perception between our two groups of participants. We also assessed anxiety, depression, empathy, alexithymia, high sensation seeking and catastrophizing, to investigate their potential influence on the emotional modulation of pain.
RESULTS
Thermal pain thresholds, RIII reflex recruitment curves, and responses to the psychological and pain sensitivity questionnaires were similar in the two groups. Neutral, positive and negative images modulated the RIII reflex similarly in the two groups. By contrast, masochistic images induced a significant (p < 0.01) decrease in RIII reflex responses in subjects with MB, whereas it tended to increase these responses in control subjects.
CONCLUSIONS
Our data suggest that psychological profile, basal pain sensitivity and the emotional modulation of pain are normal in individuals with MB but that these subjects selectively engage descending pain inhibition in the masochistic context.
SIGNIFICANCE
Decrease pain perception related to masochistic behaviours is associated with specific activation of descending pain inhibition.
Topics: Electric Stimulation; Humans; Male; Pain; Pain Perception; Pain Threshold; Reflex
PubMed: 36094743
DOI: 10.1002/ejp.2037 -
Psychiatria Danubina 2023Pain is one of the basic defense responses of living organisms. Although the threshold for pain perception varies from person to person, there is no doubt that pain... (Review)
Review
INTRODUCTION
Pain is one of the basic defense responses of living organisms. Although the threshold for pain perception varies from person to person, there is no doubt that pain reduces a person's quality of life. Assessing the subjective experience of pain is especially important in the treatment of patients with schizophrenia. In light of recent advances in neuroscience, we discuss pain thresholds in patients with schizophrenia.
METHODS
A narrative review of pain thresholds in patients with schizophrenia was conducted. We electronically searched the PubMed and Google Scholar databases for articles in English with "pain," "schizophrenia," "neural circuits," and "neurotransmitters" in the title or abstract, for the period January 2000 through June 2022.
RESULTS
A seemingly contradictory phenomenon has been noted with regard to pain thresholds in patients with schizophrenia. One phenomenon is a high pain threshold for nociceptive stimuli, and the other is a low pain threshold in chronic pain. As a result, a pain threshold paradox has been observed.
CONCLUSIONS
Many schizophrenia patients appear to have an excess of dopamine in the mesolimbic system, which stimulates both the descending pain inhibitory pathway and the salience network. As a result, a pain threshold paradox has been observed, in which the threshold for acute nociceptive pain is high and the threshold for chronic pain is low.
Topics: Humans; Pain Threshold; Chronic Pain; Quality of Life; Schizophrenia; Pain Perception
PubMed: 37480304
DOI: 10.24869/psyd.2023.174 -
Pain Medicine (Malden, Mass.) Nov 2020Music has been shown to modulate pain, although the impact of music on specific aspects of nociceptive processing is less well understood. Using quantitative sensory...
OBJECTIVE
Music has been shown to modulate pain, although the impact of music on specific aspects of nociceptive processing is less well understood. Using quantitative sensory testing (QST), we assessed the impact of a novel music app on specific aspects of nociceptive processing.
DESIGN
Within-subjects paired comparison of pain processing in control vs music condition.
SETTING
Human psychophysical laboratory.
SUBJECTS
Sixty healthy adult volunteers.
METHODS
Subjects were assessed for baseline anxiety, depression, and catastrophizing using validated questionnaires. QSTs measured included 1) pain threshold and tolerance to deep muscle pressure, 2) pain with mechanical pinprick, 3) temporal summation of pain (TSP) with a repeated pain stimulus, and 4) conditioned pain modulation (CPM) with a second painful stimulus. QSTs were performed in the absence and presence of music delivered through a music app.
RESULTS
We found an increase in pressure pain thresholds in both the forearm (P = 0.007) and trapezius (P = 0.002) with music, as well as a decrease in the amount of pinprick pain (P < 0.001) and TSP (P = 0.01) with music. Interestingly, CPM was also significantly diminished (P < 0.001) in the music condition. No significant difference in cold pain, anxiety, or situational catastrophizing was observed with music. Higher baseline pain catastrophizing scores were associated with less music-induced pressure pain reduction.
CONCLUSIONS
Several measures of mechanical pain sensitivity were reduced with music. TSP, a measure of central sensitization, also decreased with music, but CPM, a measure of descending modulation of pain, was not further augmented by music.
Topics: Adult; Humans; Music; Nociception; Pain; Pain Measurement; Pain Threshold
PubMed: 32337605
DOI: 10.1093/pm/pnaa070 -
Clinical and Experimental Rheumatology Jun 2022Fibromyalgia (FM) is associated with central pain sensitisation, autonomic alterations and neuropathy in small nerve fibres. This study aimed to analyse the association...
OBJECTIVES
Fibromyalgia (FM) is associated with central pain sensitisation, autonomic alterations and neuropathy in small nerve fibres. This study aimed to analyse the association between tonic sweating and central pain sensitisation in FM.
METHODS
Fifty-eight FM patients and thirty healthy women were assessed in terms of slowly repeated evoked pain (SREP), as a measure of central sensitisation. Sweating was evaluated by skin conductance (SC), as a sympathetic autonomic measure secondarily indexing possible small nerve fibre peripheral neuropathy. Clinical and psychological factors were evaluated through questionnaire measures.
RESULTS
FM patients displayed smaller SC values than healthy controls, and SREP sensitisation was only observed in FM patients. Pain threshold and tolerance were also lower in the patient sample. Clinical symptoms (pain, fatigue, insomnia) only correlated significantly with SREP sensitisation. SC was inversely related to SREP sensitisation, and this association persisted after statistically controlling for levels of catastrophising and antidepressant use.
CONCLUSIONS
These results suggest that central pain sensitisation, proposed as a main pathophysiological mechanism of FM, may depend on sympathetic autonomic deficiencies, suggestive of small nerve fibres neuropathy. Future studies should aim to replicate these results using other central pain sensitisation measures and direct measures of neuropathy or small nerve fibre density.
Topics: Central Nervous System Sensitization; Female; Fibromyalgia; Humans; Pain; Pain Measurement; Pain Threshold
PubMed: 35748717
DOI: 10.55563/clinexprheumatol/n280oi -
Pain Medicine (Malden, Mass.) Dec 2022Fibromyalgia syndrome (FMS) is a chronic widespread pain condition with mixed peripheral and central contributions. Patients display hypersensitivities to a spectrum of...
BACKGROUND
Fibromyalgia syndrome (FMS) is a chronic widespread pain condition with mixed peripheral and central contributions. Patients display hypersensitivities to a spectrum of stimuli. Patients' blunt pressure pain thresholds are typically reduced, and sometimes (∼15%) gentle brushstroke induces allodynia. However, aftersensations after these stimuli have not, to our knowledge, been reported.
METHODS
We examined the perception of blunt pressure and "pleasant touch" in FMS. Patients were first interviewed and completed standard psychometric questionnaires. We then measured their sensitivity to blunt pressure and perception of pleasant touch, including aftersensations; patients were followed up for 5 days to evaluate lingering pain from blunt pressure.
RESULTS
We recruited 51 patients with FMS and 16 pain-free healthy controls (HCs) at a UK Pain Management Centre. Forty-four patients completed the aftersensation protocol. Most patients reported pain after the application of less mechanical pressure than the level of pressure at which HCs reported pain; median arm and leg thresholds for the patients with FMS were 167 kPa and 233 kPa, respectively. Eighty-four percent (31/37) of patients reported ongoing pain at the site of pressure application 1 day after testing, and 49% (18/37) still perceived pain at 5 days. Aftersensations after brushstroke were common in the FMS group, reported by 77% (34/44) of patients with FMS vs 25% (4/16) of HCs; 34% (15/44) of patients, but no HCs, perceived these aftersensations as uncomfortable. For patients with FMS who experienced aftersensations, brushstroke pleasantness ratings were reduced, and the skin was often an important site of pain.
CONCLUSION
Pain after blunt pressure assessment typically lingers for several days. Aftersensations after brushstroke stimulation are a previously unreported FMS phenomenon. They are associated with tactile anhedonia and might identify a clinically distinct subgroup.
Topics: Humans; Fibromyalgia; Pain Measurement; Pain Threshold; Chronic Pain; Hyperalgesia
PubMed: 35652761
DOI: 10.1093/pm/pnac089 -
Pain Medicine (Malden, Mass.) Mar 2017The purpose of this study was to examine psychosocial influences on exercise-induced hypoalgesia (EIH). (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
The purpose of this study was to examine psychosocial influences on exercise-induced hypoalgesia (EIH).
DESIGN
Randomized controlled trial.
SETTING
Clinical research unit in a hospital.
SUBJECTS
Fifty-eight healthy men and women (mean age = 21 ± 3 years) participated in this study.
METHODS
Participants were first asked to complete a series of baseline demographic and psychological questionnaires including the Pain Catastrophizing Scale, the Fear of Pain Questionnaire, and the Family Environment Scale. Following this, they were familiarized with both temporal summation of heat pain and pressure pain testing protocols. During their next session, participants completed the Profile of Mood States, rated the intensity of heat pulses, and indicated their pressure pain thresholds and ratings before and after three minutes of submaximal, isometric exercise. Situational catastrophizing was assessed at the end of the experimental session.
RESULTS
Results indicated that experimental pain sensitivity was significantly reduced after exercise ( P < 0.05). Men and women did not differ on any of the measured psychosocial variables ( P > 0.05). Positive family environments predicted attenuated pain sensitivity and greater EIH, whereas negative and chronic pain-present family environments predicted worse pain and EIH outcomes. Situational catastrophizing and negative mood state also predicted worse pain and EIH outcomes and were additionally associated with increased ratings of perceived exertion and muscle pain during exercise.
CONCLUSIONS
This study provides preliminary evidence that psychosocial variables, such as the family environment and mood states, can affect both pain sensitivity and the ability to modulate pain through exercise-induced hypoalgesia.
Topics: Exercise; Female; Humans; Male; Naltrexone; Narcotic Antagonists; Pain; Pain Threshold; Psychology; Young Adult
PubMed: 28034985
DOI: 10.1093/pm/pnw275 -
The Clinical Journal of Pain Jul 2022Pain sensitivity and the brain structure are critical in modulating pain and may contribute to the maintenance of pain in older adults. However, a paucity of evidence...
OBJECTIVES
Pain sensitivity and the brain structure are critical in modulating pain and may contribute to the maintenance of pain in older adults. However, a paucity of evidence exists investigating the link between pain sensitivity and brain morphometry in older adults. The purpose of the study was to identify pain sensitivity profiles in healthy, community-dwelling older adults using a multimodal quantitative sensory testing protocol and to differentiate profiles based on brain morphometry.
MATERIALS AND METHODS
This study was a secondary analysis of the Neuromodulatory Examination of Pain and Mobility Across the Lifespan (NEPAL) study. Participants completed demographic and psychological questionnaires, quantitative sensory testing, and a neuroimaging session. A Principal Component Analysis with Varimax rotation followed by hierarchical cluster analysis identified 4 pain sensitivity clusters (the "pain clusters").
RESULTS
Sixty-two older adults ranging from 60 to 94 years old without a specific pain condition (mean [SD] age=71.44 [6.69] y, 66.1% female) were analyzed. Four pain clusters were identified characterized by (1) thermal pain insensitivity; (2) high pinprick pain ratings and pressure pain insensitivity; (3) high thermal pain ratings and high temporal summation; and (4) thermal pain sensitivity, low thermal pain ratings, and low mechanical temporal summation. Sex differences were observed between pain clusters. Pain clusters 2 and 4 were distinguished by differences in the brain cortical volume in the parieto-occipital region.
DISCUSSION
While sufficient evidence exists demonstrating pain sensitivity profiles in younger individuals and in those with chronic pain conditions, the finding that subgroups of experimental pain sensitivity also exist in healthy older adults is novel. Identifying these factors in older adults may help differentiate the underlying mechanisms contributing to pain and aging.
Topics: Aged; Chronic Disease; Chronic Pain; Female; Humans; Independent Living; Male; Pain Measurement; Pain Threshold; Phenotype
PubMed: 35656805
DOI: 10.1097/AJP.0000000000001048 -
Scandinavian Journal of Pain Apr 2019Background and aims Endogenous pain modulation can be studied in humans by conditioned pain modulation (CPM): pain induced by a test stimulus is attenuated by a...
Background and aims Endogenous pain modulation can be studied in humans by conditioned pain modulation (CPM): pain induced by a test stimulus is attenuated by a distantly applied noxious conditioning stimulus. The detection of impaired CPM in individual patients is of potential importance to understand the pathophysiology and predict outcomes. However, it requires the availability of reference values. Methods We determined reference values of CPM in 146 pain-free subjects. Pressure and electrical stimulation were the test stimuli. For electrical stimuli, we recorded both pain threshold and threshold for the nociceptive withdrawal reflex. Cold pressor test was the conditioning stimulus. The 5th, 10th and 25th percentiles for the three tests were computed by quantile regression analyses. Results The average thresholds increased after the conditioning stimulus for all three tests. However, a subset of subjects displayed a decrease in thresholds during the conditioning stimulus. This produced negative values for most of the computed percentiles. Conclusions This study determined percentile reference values of CPM that can be used to better phenotype patients for clinical and research purposes. The negative value of percentiles suggests that a slightly negative CPM effect can be observed in pain-free volunteers. Implications Pain facilitation rather than inhibition during the conditioning stimulus occurs in some pain-free volunteers and may not necessarily represent an abnormal finding.
Topics: Adult; Conditioning, Psychological; Electric Stimulation; Female; Healthy Volunteers; Humans; Male; Pain Measurement; Pain Threshold; Pressure; Reference Values; Switzerland
PubMed: 30699074
DOI: 10.1515/sjpain-2018-0356 -
Scandinavian Journal of Pain Apr 2022The interaction between pain and cognition includes a concurrent negative effect of pain on cognitive performance and an analgesic effect of cognitive distraction on...
OBJECTIVES
The interaction between pain and cognition includes a concurrent negative effect of pain on cognitive performance and an analgesic effect of cognitive distraction on pain experience. The purpose of this exploratory study was to investigate the role of pain intensity and task complexity on this interaction.
METHODS
Two experiments were conducted in healthy volunteers. In both experiments, participants completed 3 conditions: a pain only condition (consisting of the cold pressor test), a cognition only condition (consisting of the cognitive task) and a combined condition (concurrent administration of the cold pressor and cognitive task). In experiment I, participants performed one out of three possible tasks that differed in cognitive load (low, medium, high). In experiment II the parameters of the pain stimulus, induced by a cold pressor test, were adapted and only the high load cognitive task was employed. Pain scores, reaction times, and accuracy rates were recorded.
RESULTS
In experiment I, cognitive distraction significantly decreased pain scores, irrespective of the cognitive load of the task. Pain did not affect cognitive performance. In experiment II, pain diminished accuracy rates. No effect of cognitive distraction on pain was observed. Individual characteristics did not noticeably influence the interaction between pain and cognition.
CONCLUSIONS
The results of this study suggest a two-way interaction, however no evidence for a simultaneous bidirectional relationship was found. Cognitive distraction successfully reduces pain, up until a certain point where this relationship is reversed, and pain starts to interfere with cognitive performance. This may imply that priorities shift at a certain pain-threshold, however further research should confirm this hypothesis. This study could contribute to further understanding of cognitive mechanisms related to pain perception.
Topics: Attention; Cognition; Humans; Pain; Pain Measurement; Pain Threshold
PubMed: 34727588
DOI: 10.1515/sjpain-2021-0119 -
Musculoskeletal Science & Practice Aug 2023Evidence on the acute impact of high-intensity interval aerobic exercise on pain is scarce. This type of exercise might be perceived as increasing pain intensity and... (Randomized Controlled Trial)
Randomized Controlled Trial
Pain intensity and pain sensitivity are not increased by a single session of high-intensity interval aerobic exercise in individuals with chronic low back pain: A randomized and controlled trial.
BACKGROUND
Evidence on the acute impact of high-intensity interval aerobic exercise on pain is scarce. This type of exercise might be perceived as increasing pain intensity and pain sensitivity negatively impacting adherence. More evidence on the acute effects of high-intensity interval aerobic exercise in individuals with low back pain (LBP) is needed.
OBJECTIVES
To compare the acute effects of a single session of high-intensity interval aerobic exercise, continuous moderate-intensity aerobic exercise, and no exercise on pain intensity and pain sensitivity in patients with chronic non-specific LBP.
DESIGN
Randomized controlled trial with three arms.
METHOD
Participants were randomly assigned to one of three groups (i) continuous moderate-intensity aerobic exercise, ii) high-intensity interval aerobic exercise, and iii) no intervention. Measures of pain intensity and pressure pain threshold (PPT) at the lower back and at a distant body site (upper limb) were taken before and after 15 min of exercise.
RESULTS
Sixty-nine participants were randomized. A significant main effect of time was found for pain intensity (p = 0.011; η2p = 0.095) and for PPT at the lower back (p < 0.001; η2p = 0.280), but not a time versus group interaction (p > 0.05). For PPT at the upper limb, no main effect of time or interaction was found (p > 0.5).
CONCLUSIONS
Fifteen minutes of high-intensity interval aerobic exercise does not increase pain intensity or pain sensitivity compared to both moderate-intensity continuous aerobic exercise and no exercise, suggesting that high-intensity interval aerobic exercise can be used in clinical practice and patients reassured that it is unlikely to increase pain.
Topics: Humans; Pain Threshold; Pain Measurement; Low Back Pain; Exercise
PubMed: 37421759
DOI: 10.1016/j.msksp.2023.102824