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Meier IM, Eikemo M, Trøstheim M, Buen K, Jensen E, Gurandsrud Karlsen S, Reme SE, Berna C, Leknes S, Ernst G. Factors associated with use of opioid rescue medication after surgery. Reg Anesth Pain Med 2024; 49:265-271. [PMID: 37479238 DOI: 10.1136/rapm-2023-104412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 06/23/2023] [Indexed: 07/23/2023]
Abstract
BACKGROUND Opioid exposure after surgery increases risk of persistent opioid use. Here, we characterize at-home use of opioid rescue medication during 1-2 days after outpatient surgery (N=270) in a postoperative opioid-sparing context at a Norwegian hospital. METHODS The postsurgical pain management plan included non-steroidal anti-inflammatory drugs and up to six pills of 5 mg oxycodone as rescue analgesics. In this observational study we assessed risk factors for taking rescue opioids after surgery, by comparing patients who did, with those who did not. RESULTS Only 35% (N=228) of patients reported taking rescue opioids 1-2 days after discharge. Patients taking rescue opioids after surgery (opioid-takers) differed from non-takers by prevalence of preoperative chronic pain (>3 months; 74% vs 48%), higher pain severity and interference before and after surgery, reporting lower ability to cope with postsurgical pain, higher nervousness about the surgery, being younger, and having received more opioid analgesics in the recovery room. Exploratory predictive modeling identified opioid administration in the recovery room as the most important predictor of at-home rescue medication use. Follow-up after >4 months indicated low acute pain levels (mean±SD = 1.1±1.8), with only four patients (2%, N=217) reporting opioid analgesic use. CONCLUSION Factors related to at-home rescue medication use closely mirrored known risk factors for persistent opioid use after surgery, such as prior chronic pain, prior substance use, affective disturbances, and pain severity before surgery. These findings are potential targets in patient-centered care. Nevertheless, and reassuringly, findings are consistent with the idea that opioid-sparing postsurgical care can prevent large-scale chronic opioid use.
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Affiliation(s)
- Isabell M Meier
- Department of Physics and Computational Radiology, Oslo University Hospital, Oslo, Norway
| | - Marie Eikemo
- Department of Physics and Computational Radiology, Oslo University Hospital, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Martin Trøstheim
- Department of Physics and Computational Radiology, Oslo University Hospital, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Kaja Buen
- Department of Anesthesiology, Kongsberg Hospital, Vestre Viken Hospital Trust, Kongsberg, Norway
| | - Eira Jensen
- Department of Anesthesiology, Kongsberg Hospital, Vestre Viken Hospital Trust, Kongsberg, Norway
| | - Siri Gurandsrud Karlsen
- Department of Anesthesiology, Kongsberg Hospital, Vestre Viken Hospital Trust, Kongsberg, Norway
| | - Silje E Reme
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Pain Management and Research, Oslo University Hospital, Oslo, Norway
| | - Chantal Berna
- Centre of Integrative and Complementary Medicine, Division of Anaesthesiology, Lausanne University Hospital, Lausanne, Switzerland
| | - Siri Leknes
- Department of Physics and Computational Radiology, Oslo University Hospital, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Gernot Ernst
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Anesthesiology, Kongsberg Hospital, Vestre Viken Hospital Trust, Kongsberg, Norway
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Scarth M, Hauger LE, Thorsby PM, Leknes S, Hullstein IR, Westlye LT, Bjørnebekk A. Supraphysiological testosterone levels from anabolic steroid use and reduced sensitivity to negative facial expressions in men. Psychopharmacology (Berl) 2024; 241:701-715. [PMID: 37993638 DOI: 10.1007/s00213-023-06497-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 11/03/2023] [Indexed: 11/24/2023]
Abstract
RATIONALE Anabolic-androgenic steroids (AAS) are used to improve physical performance and appearance, but have been associated with deficits in social cognitive functioning. Approximately 30% of people who use AAS develop a dependence, increasing the risk for undesired effects. OBJECTIVES To assess the relationship between AAS use (current/previous), AAS dependence, and the ability to recognize emotional facial expressions, and investigate the potential mediating role of hormone levels. METHODS In total 156 male weightlifters, including those with current (n = 45) or previous (n = 34) AAS use and never-using controls (n = 77), completed a facial Emotion Recognition Task (ERT). Participants were presented with faces expressing one out of six emotions (sadness, happiness, fear, anger, disgust, and surprise) and were instructed to indicate which of the six emotions each face displayed. ERT accuracy and response time were recorded and evaluated for association with AAS use status, AAS dependence, and serum reproductive hormone levels. Mediation models were used to evaluate the mediating role of androgens in the relationship between AAS use and ERT performance. RESULTS Compared to never-using controls, men currently using AAS exhibited lower recognition accuracy for facial emotional expressions, particularly anger (Cohen's d = -0.57, pFDR = 0.03) and disgust (d = -0.51, pFDR = 0.05). Those with AAS dependence (n = 47) demonstrated worse recognition of fear relative to men without dependence (d = 0.58, p = 0.03). Recognition of disgust was negatively correlated with serum free testosterone index (FTI); however, FTI did not significantly mediate the association between AAS use and recognition of disgust. CONCLUSIONS Our findings demonstrate impaired facial emotion recognition among men currently using AAS compared to controls. While further studies are needed to investigate potential mechanisms, our analysis did not support a simple mediation effect of serum FTI.
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Affiliation(s)
- Morgan Scarth
- Anabolic Androgenic Steroid Research Group, Section for Clinical Addiction Research, Division of Mental Health and Addiction, Oslo University Hospital, Postbox 4959, Nydalen, 0424, Oslo, Norway.
- Department of Psychology, University of Oslo, Oslo, Norway.
| | - Lisa Evju Hauger
- Anabolic Androgenic Steroid Research Group, Section for Clinical Addiction Research, Division of Mental Health and Addiction, Oslo University Hospital, Postbox 4959, Nydalen, 0424, Oslo, Norway
| | - Per Medbøe Thorsby
- Hormone laboratory, Department of Medical Biochemistry and Biochemical endocrinology and metabolism research group, Oslo University Hospital, Oslo, Norway
- Institute of Clinical Medicine and University of Oslo, Oslo, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
| | - Ingunn R Hullstein
- Norwegian Doping Control Laboratory, Oslo University Hospital, Oslo, Norway
| | - Lars T Westlye
- Department of Psychology, University of Oslo, Oslo, Norway
- NORMENT, Division of Mental Health and Addiction, Oslo University Hospital & Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- KG Jebsen Centre for Neurodevelopmental Disorders, University of Oslo, Oslo, Norway
| | - Astrid Bjørnebekk
- Anabolic Androgenic Steroid Research Group, Section for Clinical Addiction Research, Division of Mental Health and Addiction, Oslo University Hospital, Postbox 4959, Nydalen, 0424, Oslo, Norway
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Eikemo M, Meier IM, Løseth GE, Trøstheim M, Ørstavik N, Jensen EN, Garland EL, Berna C, Ernst G, Leknes S. Opioid analgesic effects on subjective well-being in the operating theatre. Anaesthesia 2023; 78:1102-1111. [PMID: 37381617 DOI: 10.1111/anae.16069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2023] [Indexed: 06/30/2023]
Abstract
Exposure to opioid analgesics due to surgery increases the risk of new persistent opioid use. A mechanistic hypothesis for opioids' abuse liability rests on the belief that, in addition to pain relief, acute opioid treatment improves well-being (e.g. via euphoria) and relieves anxiety. However, opioids do not consistently improve mood in laboratory studies of healthy non-opioid users. This observational study determined how two commonly used opioid analgesics affected patients' subjective well-being in standard clinical practice. Day surgery patients rated how good and how anxious they felt before and after an open-label infusion of remifentanil (n = 159) or oxycodone (n = 110) in the operating theatre before general anaesthesia. One minute after drug injection, patients reported feeling intoxicated (> 6/10 points). Anxiety was reduced after opioids, but this anxiolytic effect was modest (remifentanil Cohen's d = 0.21; oxycodone d = 0.31). There was moderate to strong evidence against a concurrent improvement in well-being (Bayes factors > 6). After remifentanil, ratings of 'feeling good' were significantly reduced from pre-drug ratings (d = 0.28). After oxycodone, one in three participants felt better than pre-drug. Exploratory ordered logistic regressions revealed a link between previous opioid exposure and opioid effects on well-being, as only 14 of the 80 opioid-naïve patients reported feeling better after opioid injection. The odds of improved well-being ratings after opioids were higher in patients with previous opioid exposure and highest in patients with > 2 weeks previous opioid use (adjusted OR = 4.4). These data suggest that opioid-induced improvement of well-being is infrequent in opioid-naïve patients. We speculate that peri-operative exposure could increase risk of persistent use by rendering subsequent positive opioid effects on well-being more likely.
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Affiliation(s)
- M Eikemo
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - I M Meier
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - G E Løseth
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
| | - M Trøstheim
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - N Ørstavik
- Department of Psychology, University of Oslo, Oslo, Norway
| | - E N Jensen
- Department of Psychology, University of Oslo, Oslo, Norway
| | - E L Garland
- College of Social Work, University of Utah, Salt Lake City, Utah, USA
- Center on Mindfulness and Integrative Health Intervention Development, University of Utah, Salt Lake City, Utah, USA
| | - C Berna
- Center for Integrative and Complementary Medicine, Division of Anaesthesiology, Lausanne University Hospital, Lausanne, Switzerland
- The Sense, Lausanne University, Switzerland
| | - G Ernst
- Department of Psychology, University of Oslo, Oslo, Norway
- Kongsberg Hospital, Kongsberg, Norway
| | - S Leknes
- Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
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Trøstheim M, Eikemo M, Haaker J, Frost JJ, Leknes S. Opioid antagonism in humans: a primer on optimal dose and timing for central mu-opioid receptor blockade. Neuropsychopharmacology 2023; 48:299-307. [PMID: 35978096 PMCID: PMC7613944 DOI: 10.1038/s41386-022-01416-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/06/2022] [Accepted: 07/28/2022] [Indexed: 12/26/2022]
Abstract
Non-human animal studies outline precise mechanisms of central mu-opioid regulation of pain, stress, affiliation and reward processing. In humans, pharmacological blockade with non-selective opioid antagonists such as naloxone and naltrexone is typically used to assess involvement of the mu-opioid system in such processing. However, robust estimates of the opioid receptor blockade achieved by opioid antagonists are missing. Dose and timing schedules are highly variable and often based on single studies. Here, we provide a detailed analysis of central opioid receptor blockade after opioid antagonism based on existing positron emission tomography data. We also create models for estimating opioid receptor blockade with intravenous naloxone and oral naltrexone. We find that common doses of intravenous naloxone (0.10-0.15 mg/kg) and oral naltrexone (50 mg) are more than sufficient to produce full blockade of central MOR (>90% receptor occupancy) for the duration of a typical experimental session (~60 min), presumably due to initial super saturation of receptors. Simulations indicate that these doses also produce high KOR blockade (78-100%) and some DOR blockade (10% with naltrexone and 48-74% with naloxone). Lower doses (e.g., 0.01 mg/kg intravenous naloxone) are estimated to produce less DOR and KOR blockade while still achieving a high level of MOR blockade for ~30 min. The models and simulations form the basis of two novel web applications for detailed planning and evaluation of experiments with opioid antagonists. These tools and recommendations enable selection of appropriate antagonists, doses and assessment time points, and determination of the achieved receptor blockade in previous studies.
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Affiliation(s)
- Martin Trøstheim
- Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway. .,Department of Psychology, University of Oslo, Oslo, Norway.
| | - Marie Eikemo
- grid.5510.10000 0004 1936 8921Department of Psychology, University of Oslo, Oslo, Norway
| | - Jan Haaker
- grid.13648.380000 0001 2180 3484Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Siri Leknes
- grid.55325.340000 0004 0389 8485Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway ,grid.5510.10000 0004 1936 8921Department of Psychology, University of Oslo, Oslo, Norway
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5
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Løseth GE, Eikemo M, Trøstheim M, Meier IM, Bjørnstad H, Asratian A, Pazmandi C, Tangen VW, Heilig M, Leknes S. Stress recovery with social support: A dyadic stress and support task. Psychoneuroendocrinology 2022; 146:105949. [PMID: 36240542 DOI: 10.1016/j.psyneuen.2022.105949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 08/31/2022] [Accepted: 10/03/2022] [Indexed: 02/25/2023]
Abstract
How does social support bolster resilience? Here, we present a new dyadic paradigm to study causal mechanisms of acute and ecologically valid social support in the laboratory. The Dyadic Stress and Support Task (DSST) consists of a psychosocial stress phase and a recovery phase. During DSST stress, a pair of participants take turns to perform public speaking and mental arithmetic in front of a panel. Unable to see or touch each other, they witness each other's performance and feedback. During DSST recovery, the pair either interact freely with each other for 5 min (social support condition) or interact separately with an experimenter (non-support condition). To establish the validity of the DSST, we tested 21 pairs of long-term close friends in a pilot study. Primary outcome measures were ratings of affective state and bodily arousal (VAS scales 0-100). Secondary outcome measures were heart rate and salivary cortisol. DSST stress successfully induced subjective Stress Activation, increased Negative Affect and decreased Positive Affect. We also observed increased heart rate and salivary cortisol. After DSST recovery, Stress Activation and Negative Affect ratings were reduced in both groups. Positive Affect was completely restored to pre-stress baseline levels in the Social support group, while remaining significantly lower in the Non-support group. The DSST successfully induced stress and negative affect and captured stress recovery in both groups. Free-form interaction with the friend enhanced recovery of affective state, supporting the validity of spontaneous interaction between friends as a model of social support.
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Affiliation(s)
| | - Marie Eikemo
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Martin Trøstheim
- Department of Psychology, University of Oslo, Oslo, Norway; Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
| | - Isabell M Meier
- Department of Psychology, University of Oslo, Oslo, Norway; Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
| | - Herman Bjørnstad
- Department of Psychology, University of Oslo, Oslo, Norway; Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Anna Asratian
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden; Centre for Social and Affective Neuroscience, Linköping University, Linköping, Sweden
| | | | | | - Markus Heilig
- Centre for Social and Affective Neuroscience, Linköping University, Linköping, Sweden
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo, Norway; Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
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6
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Skoglund C, Leknes S, Heilig M. The partial µ-opioid agonist buprenorphine in autism spectrum disorder: a case report. J Med Case Rep 2022; 16:152. [PMID: 35422015 PMCID: PMC9011926 DOI: 10.1186/s13256-022-03384-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 03/11/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
There are currently no approved medications for impaired social cognition and function, core symptoms of autism spectrum disorder. We describe marked improvement of these symptoms with long-term low-dose administration of the partial µ-opioid agonist buprenorphine. We discuss these observations in the context of a role for endogenous opioid systems in social attachment, and theories integrating those findings mechanistically with autism spectrum disorder.
Case presentation
M, a 43-year-old Caucasian male, is medically healthy. Despite social difficulties since childhood, he completed high school with better-than-average grades, but failed university education. A psychiatric evaluation in his twenties diagnosed attention deficit hyperactivity disorder but also noted symptoms of coexisting autism spectrum disorder. M accidentally came across buprenorphine in his late twenties and experienced progressively improved social functioning on a low daily dosage (0.5–1.0 mg/day), an effect maintained for 15 years. He lived independently and maintained a part-time occupation. After abrupt discontinuation of treatment, his autistic symptoms returned, and function deteriorated. Following evaluation by our team, buprenorphine was resumed, with gradual return to prior level of functioning. An attempt to formally evaluate M both on and off medication was agreed with him and approved by the Swedish Ethics Authority, but medication had to be resumed when the patient worsened following discontinuation.
Conclusions
According to the µ-opioid receptor balance model, both excessive and deficient μ-receptor activity may negatively influence social behavior, and accordingly both opioid agonist and opioid antagonist treatment may be able to improve social functioning, depending on an individual’s opioid tone before treatment. Our case report is consistent with these hypotheses, and given the extensive unmet medical needs in individuals with autism spectrum disorders, randomized controlled trial appears warranted.
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Parisi A, Landicho HL, Hudak J, Leknes S, Froeliger B, Garland EL. Emotional distress and pain catastrophizing predict cue-elicited opioid craving among chronic pain patients on long-term opioid therapy. Drug Alcohol Depend 2022; 233:109361. [PMID: 35278786 PMCID: PMC9466292 DOI: 10.1016/j.drugalcdep.2022.109361] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/08/2022] [Accepted: 02/14/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND Individuals who use illicit substances exhibit cue-elicited craving and autonomic cue-reactivity when exposed to cues associated with past drug use. However, little is known about this phenomenon among chronic pain patients on long-term opioid therapy (LTOT). Negative cognitive-emotional reactivity in general (e.g., distress) and cognitive-emotional reactivity specific to pain (e.g., pain catastrophizing) might drive cue-reactivity independent of pain severity. Here we examined emotional distress and pain catastrophizing as predictors of cue-reactivity among a sample of chronic pain patients receiving LTOT. We also tested whether associations between distress, catastrophizing, and cue-reactivity differed as a function of opioid misuse status. MATERIALS AND METHODS Patients receiving LTOT (N = 243) were classified as exhibiting aberrant behavior consistent with opioid misuse (MISUSE+, n = 145) or as using opioids as prescribed (MISUSE-, n = 97). Participants completed assessments of pain catastrophizing and emotional distress and then participated in an opioid cue-reactivity task one week later. Cue-elicited opioid craving and autonomic cue-reactivity were measured with craving ratings and high-frequency heart rate variability (HRV), respectively. RESULTS Distress and catastrophizing predicted cue-elicited craving and HRV, whereas pain severity did not. Misuser status moderated the relationship between emotional distress and self-reported craving, such that higher levels of distress predicted craving among the MISUSE+ group, but not among the MISUSE- group. No moderating effects were found for catastrophizing. CONCLUSIONS Findings suggest that although opioids are prescribed for analgesia, the exacerbating influence of negative cognitive-emotional reactivity, both in general and specific to pain, on cue-elicited opioid craving extends beyond the effects of pain severity alone.
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Affiliation(s)
- Anna Parisi
- Center on Mindfulness and Integrative Health Intervention Development, University of Utah, USA; College of Social Work, University of Utah, USA
| | - Hannah Louise Landicho
- Center on Mindfulness and Integrative Health Intervention Development, University of Utah, USA; College of Social Work, University of Utah, USA
| | - Justin Hudak
- Center on Mindfulness and Integrative Health Intervention Development, University of Utah, USA; College of Social Work, University of Utah, USA
| | - Siri Leknes
- Department of Psychology, University of Oslo, USA
| | - Brett Froeliger
- Department of Psychiatry; Department of Psychological Sciences, University of Missouri, USA
| | - Eric L. Garland
- Center on Mindfulness and Integrative Health Intervention Development, University of Utah, USA; College of Social Work, University of Utah, USA
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9
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Henningsson S, Leknes S, Asperholm M, Eikemo M, Westberg L. A randomized placebo-controlled intranasal oxytocin study on first impressions and reactions to social rejection. Biol Psychol 2021; 164:108164. [PMID: 34331996 DOI: 10.1016/j.biopsycho.2021.108164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 06/21/2021] [Accepted: 07/26/2021] [Indexed: 11/20/2022]
Abstract
Oxytocin is central to pair-bonding in non-human animals. We assessed effects of intranasal oxytocin on bond formation between two opposite-sex strangers. In a double-blind placebo-controlled design, 50 pairs of one man and one woman received oxytocin or placebo spray intranasally. After treatment, they played a social interaction game, followed by tasks designed to measure first impressions of the opposite-sex co-participant, and a virtual ball-tossing game (cyberball), designed to measure reactions to rejection by the co-participant. We found no evidence that intranasal oxytocin can improve first impressions of an opposite-sex stranger, and some Bayesian support against this hypothesis. For rejection sensitivity, we observed a sex-and-context-dependent drug effect on post-ostracism mood ratings, consistent with recent studies indicating that interindividual variation and social context can interact with intranasal oxytocin effects. Further research is needed to determine the generalisability of these findings, i.e. if oxytocin can improve first impressions in humans under different conditions.
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Affiliation(s)
- Susanne Henningsson
- Department of Pharmacology, Institute of Neuroscience and Physiology at the Sahlgrenska Academy, University of Gothenburg, POB 431, 405 30 Gothenburg, Sweden
| | - Siri Leknes
- Department of Psychology, University of Oslo, POB 1094, 0317 Oslo, Norway
| | - Martin Asperholm
- Department of Psychology, University of Oslo, POB 1094, 0317 Oslo, Norway
| | - Marie Eikemo
- Department of Psychology, University of Oslo, POB 1094, 0317 Oslo, Norway
| | - Lars Westberg
- Department of Pharmacology, Institute of Neuroscience and Physiology at the Sahlgrenska Academy, University of Gothenburg, POB 431, 405 30 Gothenburg, Sweden.
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Meier IM, Eikemo M, Leknes S. The Role of Mu-Opioids for Reward and Threat Processing in Humans: Bridging the Gap from Preclinical to Clinical Opioid Drug Studies. Curr Addict Rep 2021; 8:306-318. [PMID: 34722114 PMCID: PMC8550464 DOI: 10.1007/s40429-021-00366-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2021] [Indexed: 12/22/2022]
Abstract
PURPOSE OF REVIEW Opioid receptors are widely expressed in the human brain. A number of features commonly associated with drug use disorder, such as difficulties in emotional learning, emotion regulation and anhedonia, have been linked to endogenous opioid signalling. Whereas chronic substance use and misuse are thought to alter the function of the mu-opioid system, the specific mechanisms are not well understood. We argue that understanding exogenous and endogenous opioid effects in the healthy human brain is an essential foundation for bridging preclinical and clinical findings related to opioid misuse. Here, we will examine psychopharmacological evidence to outline the role of the mu-opioid receptor (MOR) system in the processing of threat and reward, and discuss how disruption of these processes by chronic opioid use might alter emotional learning and reward responsiveness. RECENT FINDINGS In healthy people, studies using opioid antagonist drugs indicate that the brain's endogenous opioids downregulate fear reactivity and upregulate learning from safety. At the same time, endogenous opioids increase the liking of and motivation to engage with high reward value cues. Studies of acute opioid agonist effects indicate that with non-sedative doses, drugs such as morphine and buprenorphine can mimic endogenous opioid effects on liking and wanting. Disruption of endogenous opioid signalling due to prolonged opioid exposure is associated with some degree of anhedonia to non-drug rewards; however, new results leave open the possibility that this is not directly opioid-mediated. SUMMARY The available human psychopharmacological evidence indicates that the healthy mu-opioid system contributes to the regulation of reward and threat processing. Overall, endogenous opioids can subtly increase liking and wanting responses to a wide variety of rewards, from sweet tastes to feelings of being connected to close others. For threat-related processing, human evidence suggests that endogenous opioids inhibit fear conditioning and reduce the sensitivity to aversive stimuli, although inconsistencies remain. The size of effects reported in healthy humans are however modest, clearly indicating that MORs play out their role in close concert with other neurotransmitter systems. Relevant candidate systems for future research include dopamine, serotonin and endocannabinoid signalling. Nevertheless, it is possible that endogenous opioid fine-tuning of reward and threat processing, when unbalanced by e.g. opioid misuse, could over time develop into symptoms associated with opioid use disorder, such as anhedonia and depression/anxiety.
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Affiliation(s)
- Isabell M. Meier
- Department of Diagnostic Physics, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway
| | - Marie Eikemo
- Department of Psychology, University of Oslo, Blindern, 0317 Oslo, Norway
| | - Siri Leknes
- Department of Diagnostic Physics, Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway
- Department of Psychology, University of Oslo, Blindern, 0317 Oslo, Norway
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Laeng B, Garvija L, Løseth G, Eikemo M, Ernst G, Leknes S. 'Defrosting' music chills with naltrexone: The role of endogenous opioids for the intensity of musical pleasure. Conscious Cogn 2021; 90:103105. [PMID: 33711654 DOI: 10.1016/j.concog.2021.103105] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/09/2021] [Accepted: 02/17/2021] [Indexed: 01/31/2023]
Abstract
The endogenous opioid system has been implicated during experiences of pleasure (i.e., from food or sex). Music can elicit intense emotional and bodily sensations of pleasure, called 'Chills'. We investigated the effects of an opioid antagonist (50 mg naltrexone) or placebo (40 μg d3-vitamin) while listening to self-selected music or other 'control' music selected by another participant. We used a novel technique of continuous measurement of pleasantness with an eye tracker system, where participants shifted their eyes along a visual analogue scale, in the semblance of a thermometer so that, as the music unfolded, gaze positions indicated the self-reported hedonic experience. Simultaneously, we obtained pupil diameters. Self-reported pleasure remained unchanged by naltrexone, which - however - selectively decreased pupillary diameters during 'Chills'. Hence, the endogenous μ-opioid signaling is not necessary for subjective enjoyment of music but an opioid blockade dampens pupil responses to peak pleasure, consistent with decreased arousal to the music.
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Affiliation(s)
- Bruno Laeng
- Department of Psychology, University of Oslo, Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Norway.
| | - Lara Garvija
- Department of Psychology, University of Oslo, Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Norway
| | - Guro Løseth
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Marie Eikemo
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Gernot Ernst
- Department of Psychology, University of Oslo, Oslo, Norway; Vestre Viken Health Trust, Kongsberg Hospital, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo, Norway; Department of Diagnostic Physics, Oslo University Hospital, Norway
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12
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Sulutvedt U, Zavagno D, Lubell J, Leknes S, de Rodez Benavent SA, Laeng B. Brightness perception changes related to pupil size. Vision Res 2020; 178:41-47. [PMID: 33113435 DOI: 10.1016/j.visres.2020.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 11/17/2022]
Abstract
Dilating the pupils allow more quanta of light to impact the retina. Consequently, if one pupil is dilated with a pharmacological agent (Tropicamide), the brightness of a surface under observation should increase proportionally to the pupil dilation. Little is known about causal effects of changes in pupil size on perception of an object's brightness. In a psychophysical procedure of brightness adjustment and matching, we presented to one eye geometrical patterns with a central square (the reference pattern) that differed in physical brightness within backgrounds of constant luminance. Subsequently, with the other eye, participants (n = 30) adjusted to the same luminance a similar pattern (target) whose central square luminance was randomly set higher or lower in brightness than the reference. As only one eye was treated with Tropicamide, we assessed whether the subjective brightness of the target square shifted in a consistent direction when viewed with the dilated pupil compared to the untreated (control) eye. We found that, as the pupil increased post drug administration, so significantly did the sense of brightness of the pattern (i.e., higher brightness adjustments followed viewing the reference pattern with the treated (Tropicamide) eye). A reversed effect was observed when the control eye viewed the reference pattern first. The results confirm that even slight pupil dilations can result in an enhanced perceptual experience of brightness of the attended object, corresponding to an average increase of 2.09 cd/m2 for each 1 mm increase in pupil diameter.
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Affiliation(s)
- Unni Sulutvedt
- Department of Psychology, University of Oslo, Oslo, Norway.
| | - Daniele Zavagno
- Department of Psychology, University of Milano-Bicocca, Milano, Italy
| | - Jamie Lubell
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Sigrid A de Rodez Benavent
- Department of Ophthalmology, Oslo University Hospital and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Bruno Laeng
- Department of Psychology, University of Oslo, Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
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Hovey D, Martens L, Laeng B, Leknes S, Westberg L. The effect of intranasal oxytocin on visual processing and salience of human faces. Transl Psychiatry 2020; 10:318. [PMID: 32951002 PMCID: PMC7502073 DOI: 10.1038/s41398-020-00991-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 06/22/2020] [Accepted: 06/24/2020] [Indexed: 02/06/2023] Open
Abstract
The mechanisms underlying the role of oxytocin (OT) as a regulator of social behavior in mammals are only partly understood. Recently, it has been proposed that OT increases the salience of social stimuli. We carried out a randomized, double-blind, cross-over study of the effects of OT on binocular rivalry, a visual phenomenon underpinned by the interplay of excitation and inhibition in the cortex. A final sample of 45 participants viewed images of social stimuli (faces with different emotional expressions) and non-social stimuli (houses and Gabor patches). We demonstrate a robust effect that intranasal OT increases the salience of human faces in binocular rivalry, such that dominance durations of faces are longer-this effect is not modulated by the facial expression. We tentatively show that OT treatment increases dominance durations for non-social stimuli. Our results lend support to the social salience hypothesis of OT, and in addition offer provisional support for the role of OT in influencing excitation-inhibition balance in the brain.
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Affiliation(s)
- Daniel Hovey
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
| | - Louise Martens
- grid.10392.390000 0001 2190 1447Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany ,grid.419501.80000 0001 2183 0052Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Bruno Laeng
- grid.5510.10000 0004 1936 8921Department of Psychology, University of Oslo, Oslo, Norway ,RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, Oslo, Norway
| | - Siri Leknes
- grid.5510.10000 0004 1936 8921Department of Psychology, University of Oslo, Oslo, Norway
| | - Lars Westberg
- grid.8761.80000 0000 9919 9582Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Abstract
BACKGROUND Both acute and chronic pain can disrupt reward processing. Moreover, prolonged prescription opioid use and depressed mood are common in chronic pain samples. Despite the prevalence of these risk factors for anhedonia, little is known about anhedonia in chronic pain populations. METHODS We conducted a large-scale, systematic study of anhedonia in chronic pain, focusing on its relationship with opioid use/misuse, pain severity, and depression. Chronic pain patients across four distinct samples (N = 488) completed the Snaith-Hamilton Pleasure Scale (SHAPS), measures of opioid use, pain severity and depression, as well as the Current Opioid Misuse Measure (COMM). We used a meta-analytic approach to determine reference levels of anhedonia in healthy samples spanning a variety of countries and diverse age groups, extracting SHAPS scores from 58 published studies totaling 2664 psychiatrically healthy participants. RESULTS Compared to healthy samples, chronic pain patients showed higher levels of anhedonia, with ~25% of patients scoring above the standard anhedonia cut-off. This difference was not primarily driven by depression levels, which explained less than 25% of variance in anhedonia scores. Neither opioid use duration, dose, nor pain severity alone was significantly associated with anhedonia. Yet, there was a clear effect of opioid misuse, with opioid misusers (COMM ⩾13) reporting greater anhedonia than non-misusers. Opioid misuse remained a significant predictor of anhedonia even after controlling for pain severity, depression and opioid dose. CONCLUSIONS Study results suggest that both chronic pain and opioid misuse contribute to anhedonia, which may, in turn, drive further pain and misuse.
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Affiliation(s)
- Eric L Garland
- Center on Mindfulness and Integrative Health Intervention Development, University of Utah, Salt Lake City, UT, USA
- College of Social Work, University of Utah, Salt Lake City, UT, USA
| | | | - Marie Eikemo
- Department of Psychology, University of Oslo, Norway
| | - Gernot Ernst
- Department of Psychology, University of Oslo, Norway
- Kongsberg Hospital, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Norway
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15
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Trøstheim M, Eikemo M, Meir R, Hansen I, Paul E, Kroll SL, Garland EL, Leknes S. Assessment of Anhedonia in Adults With and Without Mental Illness: A Systematic Review and Meta-analysis. JAMA Netw Open 2020; 3:e2013233. [PMID: 32789515 PMCID: PMC7116156 DOI: 10.1001/jamanetworkopen.2020.13233] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
IMPORTANCE Anhedonia, a reduced capacity for pleasure, is described for many psychiatric and neurologic conditions. However, a decade after the Research Domain Criteria launch, whether anhedonia severity differs between diagnoses is still unclear. Reference values for hedonic capacity in healthy humans are also needed. OBJECTIVE To generate and compare reference values for anhedonia levels in adults with and without mental illness. DATA SOURCES Web of Science, Scopus, PubMed, and Google Scholar were used to list all articles from January 1, 1995 to July 2, 2019, citing the scale development report of a widely used anhedonia questionnaire, the Snaith-Hamilton Pleasure Scale (SHAPS). Searches were conducted from April 5 to 11, 2018, and on July 2, 2019. STUDY SELECTION Studies including healthy patients and those with a verified diagnosis, assessed at baseline or in a no-treatment condition with the complete 14-item SHAPS, were included in this preregistered meta-analysis. DATA EXTRACTION AND SYNTHESIS Random-effects models were used to calculate mean SHAPS scores and 95% CIs separately for healthy participants and patients with current major depressive disorder (MDD), past/remitted MDD, bipolar disorder, schizophrenia, substance use disorders, Parkinson disease, and chronic pain. SHAPS scores were compared between groups using meta-regression, and traditional effect size meta-analyses were conducted to estimate differences in SHAPS scores between healthy and patient samples. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. MAIN OUTCOMES AND MEASURES Self-reported anhedonia as measured by 2 different formats of the SHAPS (possible ranges, 0-14 and 14-56 points), with higher values on both scales indicating greater anhedonia symptoms. RESULTS In the available literature (168 articles; 16 494 participants; 8058 [49%] female participants; aged 13-72 years), patients with current MDD, schizophrenia, substance use disorder, Parkinson disease, and chronic pain scored higher on the SHAPS than healthy participants. Within the patient groups, those with current MDD scored considerably higher than all other groups. Patients with remitted MDD scored within the healthy range (g = 0.1). This pattern replicated across SHAPS scoring methods and was consistent across point estimate and effect size analyses. CONCLUSIONS AND RELEVANCE The findings of this meta-analysis indicate that the severity of anhedonia may differ across disorders associated with anhedonia. Whereas anhedonia in MDD affects multiple pleasure domains, patients with other conditions may experience decreased enjoyment of only a minority of life's many rewards. These findings have implications for psychiatric taxonomy development, where dimensional approaches are gaining attention. Moreover, the SHAPS reference values presented herein may be useful for researchers and clinicians assessing the efficacy of anhedonia treatments.
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Affiliation(s)
- Martin Trøstheim
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
| | - Marie Eikemo
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Remy Meir
- Department of Neuroscience, Brown University, Providence, Rhode Island
| | - Ingelin Hansen
- Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
| | - Elisabeth Paul
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Sara Liane Kroll
- Center for Social and Affective Neuroscience, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Eric L Garland
- Center on Mindfulness and Integrative Health Intervention Development, The University of Utah, Salt Lake City
- The University of Utah College of Social Work, Salt Lake City
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo, Norway
- Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
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16
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Løseth GE, Eikemo M, Leknes S. Effects of opioid receptor stimulation and blockade on touch pleasantness: a double-blind randomised trial. Soc Cogn Affect Neurosci 2020; 14:411-422. [PMID: 30951167 PMCID: PMC6523440 DOI: 10.1093/scan/nsz022] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/21/2019] [Accepted: 03/23/2019] [Indexed: 11/23/2022] Open
Abstract
The μ-opioid receptor (MOR) system has long been thought to underpin the rewarding properties of pleasant touch. Numerous non-human animal studies implicate MORs in social behaviours involving touch, but little is currently known about MOR involvement in human touch reward. Here, we employed a bi-directional pharmacological double-blind crossover design to assess the role of the human MOR system for touch pleasantness and motivation. Forty-nine male volunteers received 10 mg per-oral morphine, 50 mg per-oral naltrexone and placebo before being brushed on their forearm at three different velocities (0.3, 3 and 30 cm/s). In a touch liking task, pleasantness ratings were recorded after each 15 s brushing trial. In a touch wanting task, participants actively manipulated trial duration through key presses. As expected, 3 cm/s was the preferred velocity, producing significantly higher pleasantness ratings and wanting scores than the other stimuli. Contrary to our hypothesis, MOR drug manipulations did not significantly affect either touch pleasantness or wanting. The null effects were supported by post hoc Bayesian analyses indicating that the models with no drug effect were more than 25 times more likely than the alternative models given the data. We conclude that μ-opioid signalling is unlikely to underpin non-affiliative touch reward in humans.
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Affiliation(s)
- Guro E Løseth
- Department of Psychology, University of Oslo, Blindern, N Oslo, Norway
| | - Marie Eikemo
- Department of Psychology, University of Oslo, Blindern, N Oslo, Norway.,Department of Diagnostic Physics, Oslo University Hospital, Nydalen, N Oslo, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Blindern, N Oslo, Norway
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17
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Leknes S, Atlas LY. Flawed methodology undermines conclusions about opioid-induced pleasure: implications for psychopharmacology. Br J Anaesth 2019; 124:e29-e33. [PMID: 31753290 DOI: 10.1016/j.bja.2019.10.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 09/20/2019] [Accepted: 10/16/2019] [Indexed: 11/26/2022] Open
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18
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Bastian B, Vauclair CM, Loughnan S, Bain P, Ashokkumar A, Becker M, Bilewicz M, Collier-Baker E, Crespo C, Eastwick PW, Fischer R, Friese M, Gómez Á, Guerra VM, Guevara JLC, Hanke K, Hooper N, Huang LL, Junqi S, Karasawa M, Kuppens P, Leknes S, Peker M, Pelay C, Pina A, Sachkova M, Saguy T, Silfver-Kuhalampi M, Sortheix F, Tong J, Yeung VWL, Duffy J, Swann WB. Explaining illness with evil: pathogen prevalence fosters moral vitalism. Proc Biol Sci 2019; 286:20191576. [PMID: 31662082 PMCID: PMC6842846 DOI: 10.1098/rspb.2019.1576] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 10/02/2019] [Indexed: 01/15/2023] Open
Abstract
Pathogens represent a significant threat to human health leading to the emergence of strategies designed to help manage their negative impact. We examined how spiritual beliefs developed to explain and predict the devastating effects of pathogens and spread of infectious disease. Analysis of existing data in studies 1 and 2 suggests that moral vitalism (beliefs about spiritual forces of evil) is higher in geographical regions characterized by historical higher levels of pathogens. Furthermore, drawing on a sample of 3140 participants from 28 countries in study 3, we found that historical higher levels of pathogens were associated with stronger endorsement of moral vitalistic beliefs. Furthermore, endorsement of moral vitalistic beliefs statistically mediated the previously reported relationship between pathogen prevalence and conservative ideologies, suggesting these beliefs reinforce behavioural strategies which function to prevent infection. We conclude that moral vitalism may be adaptive: by emphasizing concerns over contagion, it provided an explanatory model that enabled human groups to reduce rates of contagious disease.
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Affiliation(s)
- Brock Bastian
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Victoria, Australia
| | | | - Steve Loughnan
- School of Philosophy, Psychology and Language Sciences, University of Edinburgh, Edinburgh, UK
| | - Paul Bain
- Department of Psychology, University of Bath, Bath, Somerset, UK
| | - Ashwini Ashokkumar
- Department of Psychology, The University of Texas at Austin, Austin, TX, USA
| | - Maja Becker
- CLLE, Université de Toulouse, CNRS, UT2J, Toulouse, Midi-Pyrénées, France
| | - Michał Bilewicz
- Department of Psychological and Brain Sciences, University of Warsaw, Warszawa, Poland
| | - Emma Collier-Baker
- School of Psychology, University of Queensland, Brisbane, Queensland, Australia
- Forest, Nature and Environment Aceh, Banda Aceh City, Aceh, Indonesia
| | - Carla Crespo
- Faculty of Psychology, University of Lisbon, Lisboa, Portugal
| | - Paul W. Eastwick
- Department of Psychology, University of California, Davis, CA, USA
| | - Ronald Fischer
- School of Psychology, Victoria University of Wellington, Wellington, New Zealand
| | - Malte Friese
- Department of Psychology, Saarland University, Saarbrucken, Saarland, Germany
| | - Ángel Gómez
- Department of Social and Organizational Psychology, Universidad Nacional de Educacion a Distancia, Madrid, Spain
| | - Valeschka M. Guerra
- Department of Psychology, Universidade Federal do Espirito Santo, Vitoria, Brazil
| | | | - Katja Hanke
- University of Applied Management Studies, Mannheim, Baden-Wurttemberg, Germany
| | - Nic Hooper
- Health and Social Sciences, University of the West of England, Bristol, UK
| | - Li-Li Huang
- School of Economics and Management, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Shi Junqi
- Lingnan College, Sun Yat-Sen University, Guangzhou, Guangdong, People's Republic of China
| | - Minoru Karasawa
- Department of Psychology, Nagoya University, Nagoya, Aichi, Japan
| | - Peter Kuppens
- Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Flanders, Belgium
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Müjde Peker
- Department of Psychology, MEF University, Istanbul, Turkey
| | - Cesar Pelay
- Universidad Central de Venezuela, Caracas, Distrito Capital, Bolivarian Republic of Venezuela
| | - Afroditi Pina
- School of Psychology, University of Kent, Canterbury, Kent, UK
| | - Marianna Sachkova
- Russian Presidential Academy of National Economy and Public Administration, Moskva, Russian Federation
| | - Tamar Saguy
- Interdisciplinary Center (IDC) Herzliya, Herzliya, Tel Aviv, Israel
| | | | - Florencia Sortheix
- Swedish School of Social Sciences, University of Helsinki, Helsinki, Finland
| | - Jennifer Tong
- School of Social Sciences, Singapore Management University, Singapore, Singapore
| | - Victoria Wai-lan Yeung
- Department of Applied Psychology, Lingnan University, New Territories, Hong Kong, People's Republic of China
| | - Jacob Duffy
- Melbourne School of Psychological Sciences, University of Melbourne, Melbourne, Victoria, Australia
| | - William B. Swann
- Department of Psychology, The University of Texas at Austin, Austin, TX, USA
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Hauger LE, Sagoe D, Vaskinn A, Arnevik EA, Leknes S, Jørstad ML, Bjørnebekk A. Anabolic androgenic steroid dependence is associated with impaired emotion recognition. Psychopharmacology (Berl) 2019; 236:2667-2676. [PMID: 30941469 DOI: 10.1007/s00213-019-05239-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 03/22/2019] [Indexed: 01/22/2023]
Abstract
RATIONALE Illicit use of anabolic androgenic steroids (AAS) has grown into a serious public health concern throughout the Western World. AAS use is associated with adverse medical, psychological, and social consequences. Around 30% of AAS users develop a dependence syndrome with sustained use despite adverse side effects. AAS dependence is associated with a high frequency of intra- and interpersonal problems, and it is central to identify factors related to the development and maintenance of dependence. METHODS The present study investigated the ability to recognize emotion from biological motion. The emotional biological motion task was administered to male AAS dependent users (AAS dependents; n = 45), AAS non-dependent users (AAS non-dependents; n = 38) and a comparison-group of non-using weightlifters (non-users; n = 69). RESULTS Multivariate analysis of variance showed a general impairment in emotion recognition in AAS dependents, compared to the non-using weightlifters, whereas no significant impairment was observed in AAS non-dependents. Furthermore, AAS dependents showed impaired recognition of fearful stimuli compared to both AAS non-dependents and non-using weightlifters. The between-group effect remained significant after controlling for Intelligence Quotient (IQ), past 6 months of non-AAS drug use, antisocial personality problems, anxiety, and depression. CONCLUSION AAS dependents show impaired emotion recognition from body movement, fear in particular, which could potentially contribute to higher frequency of interpersonal problems and antisocial behaviors in this population.
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Affiliation(s)
- Lisa E Hauger
- The Anabolic Androgenic Steroid Research Group, National Advisory Unit on Substance Use Disorder Treatment, the Division of Mental Health and Addiction, Oslo University Hospital, Postbox 4959, Nydalen, 0424, Oslo, Norway.
| | - Dominic Sagoe
- Department of Psychosocial Science, University of Bergen, Bergen, Norway
| | - Anja Vaskinn
- Norwegian Centre for Mental Disorders Research, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
| | - Espen A Arnevik
- The Anabolic Androgenic Steroid Research Group, National Advisory Unit on Substance Use Disorder Treatment, the Division of Mental Health and Addiction, Oslo University Hospital, Postbox 4959, Nydalen, 0424, Oslo, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo, Norway
| | - Marie L Jørstad
- The Anabolic Androgenic Steroid Research Group, National Advisory Unit on Substance Use Disorder Treatment, the Division of Mental Health and Addiction, Oslo University Hospital, Postbox 4959, Nydalen, 0424, Oslo, Norway
| | - Astrid Bjørnebekk
- The Anabolic Androgenic Steroid Research Group, National Advisory Unit on Substance Use Disorder Treatment, the Division of Mental Health and Addiction, Oslo University Hospital, Postbox 4959, Nydalen, 0424, Oslo, Norway
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20
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Eikemo M, Lobmaier PP, Pedersen ML, Kunøe N, Matziorinis AM, Leknes S, Sarfi M. Intact responses to non-drug rewards in long-term opioid maintenance treatment. Neuropsychopharmacology 2019; 44:1456-1463. [PMID: 30928994 PMCID: PMC6785711 DOI: 10.1038/s41386-019-0377-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 03/12/2019] [Accepted: 03/24/2019] [Indexed: 12/13/2022]
Abstract
Disruption of non-drug reward processing in addiction could stem from long-term drug use, addiction-related psychosocial stress, or a combination of these. It remains unclear whether long-term opioid maintenance treatment (OMT) disrupts reward processing. Here, we measured subjective and objective reward responsiveness in 26 previously heroin-addicted mothers in >7 years stable OMT with minimal psychosocial stress and illicit drug use. The comparison group was 30 healthy age-matched mothers (COMP). Objective reward responsiveness was assessed in a two-alternative forced-choice task with skewed rewards. Results were also compared to performance from an additional 968 healthy volunteers (meta-analytic approach). We further compared subprocesses of reward-based decisions across groups using computational modelling with a Bayesian drift diffusion model of decision making. Self-reported responsiveness to non-drug rewards was high for both groups (means: OMT = 6.59, COMP = 6.67, p = 0.84, BF10 = 0.29), yielding moderate evidence against subjective anhedonia in this OMT group. Importantly, the mothers in OMT also displayed robust reward responsiveness in the behavioral task (t19 = 2.72, p = 0.013, BF10 = 3.98; d = 0.61). Monetary reward changed their task behavior to the same extent as the local comparison group (reward bias OMT = 0.12, COMP = 0.12, p = 0.96, BF10 = 0.18) and in line with data from 968 healthy controls previously tested. Computational modelling revealed that long-term OMT did not even change decision subprocesses underpinning reward behavior. We conclude that reduced sensitivity to rewards and anhedonia are not necessary consequences of prolonged opioid use.
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Affiliation(s)
- Marie Eikemo
- Norwegian Centre for Addiction Research (SERAF), Faculty of Medicine, University of Oslo, Oslo, Norway. .,Division for Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. .,Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway.
| | - Philipp P. Lobmaier
- 0000 0004 1936 8921grid.5510.1Norwegian Centre for Addiction Research (SERAF), Faculty of Medicine, University of Oslo, Oslo, Norway ,0000 0004 0389 8485grid.55325.34Division for Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
| | - Mads L. Pedersen
- 0000 0004 1936 8921grid.5510.1Department of Psychology, University of Oslo, Oslo, Norway ,0000 0004 0389 8485grid.55325.34The Intervention Centre, Oslo University Hospital, Oslo, Norway
| | - Nikolaj Kunøe
- 0000 0004 1936 8921grid.5510.1Norwegian Centre for Addiction Research (SERAF), Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Anna Maria Matziorinis
- 0000 0004 1936 8921grid.5510.1Department of Psychology, University of Oslo, Oslo, Norway
| | - Siri Leknes
- 0000 0004 1936 8921grid.5510.1Department of Psychology, University of Oslo, Oslo, Norway ,0000 0004 0389 8485grid.55325.34The Intervention Centre, Oslo University Hospital, Oslo, Norway
| | - Monica Sarfi
- 0000 0004 1936 8921grid.5510.1Norwegian Centre for Addiction Research (SERAF), Faculty of Medicine, University of Oslo, Oslo, Norway
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21
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Løseth GE, Eikemo M, Isager P, Holmgren J, Laeng B, Vindenes V, Hjørnevik T, Leknes S. Morphine reduced perceived anger from neutral and implicit emotional expressions. Psychoneuroendocrinology 2018; 91:123-131. [PMID: 29550675 DOI: 10.1016/j.psyneuen.2018.02.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/27/2018] [Accepted: 02/28/2018] [Indexed: 12/20/2022]
Abstract
The μ-opioid system modulates responses to pain and psychosocial stress and mediates non-social and social reward. In humans, the μ-opioid agonist morphine can increase overt attention to the eye-region and visual exploration of faces with neutral expressions. However, little is known about how the human μ-opioid system influences sensitivity to and appraisal of subtle and explicit cues of social threats and reward. Here, we examined the effects of selective μ-opioid stimulation on perception of anger and happiness in faces with explicit, neutral or implicit emotion expressions. Sixty-three healthy adults (32 females) attended two sessions where they received either placebo or 10 mg per oral morphine in randomised order under double-blind conditions. Based on the known μ-opioid reduction of pain and discomfort, as well as reports suggesting that the non-specific partial agonist buprenorphine or the non-specific antagonist naltrexone affect appraisal of social emotional stimuli, we hypothesised that morphine would reduce threat sensitivity and enhance perception of happy facial expressions. While overall perception of others' happiness was unaffected by morphine treatment, morphine reduced perception of anger in stimuli with neutral and implicit expressions without affecting perception of explicit anger. This effect was statistically unrelated to gender, subjective drug effects, mood and autism trait measures. The finding that a low dose of μ-agonist reduced the propensity to perceive anger in photos with subtle facial expressions is consistent with the notion that μ-opioids mediate social confidence and reduce sensitivity to threat cues.
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Affiliation(s)
- Guro E Løseth
- Department of Psychology, University of Oslo, Norway.
| | - Marie Eikemo
- Department of Diagnostic Physics, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Norway; Division of Mental Health and Addiction, Oslo University Hospital, Norway
| | - Peder Isager
- Department of Psychology, University of Oslo, Norway
| | | | - Bruno Laeng
- Department of Psychology, University of Oslo, Norway
| | - Vigdis Vindenes
- Department of Forensic Medicine, Oslo University Hospital, Norway
| | - Trine Hjørnevik
- Department of Diagnostic Physics, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Norway
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Eikemo M, Biele G, Willoch F, Thomsen L, Leknes S. Opioid Modulation of Value-Based Decision-Making in Healthy Humans. Neuropsychopharmacology 2017; 42:1833-1840. [PMID: 28294136 PMCID: PMC5520785 DOI: 10.1038/npp.2017.58] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 02/20/2017] [Accepted: 03/07/2017] [Indexed: 01/08/2023]
Abstract
Modifying behavior to maximize reward is integral to adaptive decision-making. In rodents, the μ-opioid receptor (MOR) system encodes motivation and preference for high-value rewards. Yet it remains unclear whether and how human MORs contribute to value-based decision-making. We reasoned that if the human MOR system modulates value-based choice, this would be reflected by opposite effects of agonist and antagonist drugs. In a double-blind pharmacological cross-over study, 30 healthy men received morphine (10 mg), placebo, and the opioid antagonist naltrexone (50 mg). They completed a two-alternative decision-making task known to induce a considerable bias towards the most frequently rewarded response option. To quantify MOR involvement in this bias, we fitted accuracy and reaction time data with the drift-diffusion model (DDM) of decision-making. The DDM analysis revealed the expected bidirectional drug effects for two decision subprocesses. MOR stimulation with morphine increased the preference for the stimulus with high-reward probability (shift in starting point). Compared to placebo, morphine also increased, and naltrexone reduced, the efficiency of evidence accumulation. Since neither drug affected motor-coordination, speed-accuracy trade-off, or subjective state (indeed participants were still blinded after the third session), we interpret the MOR effects on evidence accumulation efficiency as a consequence of changes in effort exerted in the task. Together, these findings support a role for the human MOR system in value-based choice by tuning decision-making towards high-value rewards across stimulus domains.
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Affiliation(s)
- Marie Eikemo
- The Department of Psychology, University of Oslo, Oslo, Norway,Norwegian Center for Addiction Research, Department of Clinical Medicine, University of Oslo, Oslo, Norway,Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway,Norwegian Centre for Addiction Research, University of Oslo, PO BOX 1039 Blindern, Oslo 0315, Norway, Tel: +47 23 36 89 76, Fax: +47 23 36 89 86, E-mail:
| | - Guido Biele
- The Department of Psychology, University of Oslo, Oslo, Norway,Department of Child Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Frode Willoch
- The Department of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Lotte Thomsen
- The Department of Psychology, University of Oslo, Oslo, Norway
| | - Siri Leknes
- The Department of Psychology, University of Oslo, Oslo, Norway,The Intervention Centre, Oslo University Hospital, Oslo, Norway
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23
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Liljencrantz J, Strigo I, Ellingsen DM, Krämer HH, Lundblad LC, Nagi SS, Leknes S, Olausson H. Slow brushing reduces heat pain in humans. Eur J Pain 2017; 21:1173-1185. [PMID: 28263013 DOI: 10.1002/ejp.1018] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2017] [Indexed: 12/26/2022]
Abstract
BACKGROUND C-tactile (CT) afferents are unmyelinated low-threshold mechanoreceptors optimized for signalling affective, gentle touch. In three separate psychophysical experiments, we examined the contribution of CT afferents to pain modulation. METHODS In total, 44 healthy volunteers experienced heat pain and CT optimal (slow brushing) and CT sub-optimal (fast brushing or vibration) stimuli. Three different experimental paradigms were used: Concurrent application of heat pain and tactile (slow brushing or vibration) stimulation; Slow brushing, applied for variable duration and intervals, preceding heat pain; Slow versus fast brushing preceding heat pain. RESULTS Slow brushing was effective in reducing pain, whereas fast brushing or vibration was not. The reduction in pain was significant not only when the CT optimal touch was applied simultaneously with the painful stimulus but also when the two stimuli were separated in time. For subsequent stimulation, the pain reduction was more pronounced for a shorter time interval between brushing and pain. Likewise, the effect was more robust when pain was preceded by a longer duration of brush stimulation. Strong CT-related pain reduction was associated with low anxiety and high calmness scores obtained by a state anxiety questionnaire. CONCLUSIONS Slow brushing - optimal for CT activation - is effective in reducing pain from cutaneous heating. The precise mechanisms for the pain relief are as yet unknown but possible mechanisms include inhibition of nociceptive projection neurons at the level of the dorsal horn as well as analgesia through cortical mechanisms. SIGNIFICANCE Slow brushing stimuli - optimal for activation of C-tactile fibres - can reduce pain from cutaneous heating. No such effect was seen with fast brushing or vibration. These observations indicate the role of C-tactile fibres in pain modulation.
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Affiliation(s)
- J Liljencrantz
- Institute of Neuroscience and Physiology, University of Gothenburg, Sweden
| | - I Strigo
- VA San Francisco Healthcare System, USA.,University of California San Francisco, USA
| | - D M Ellingsen
- MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, USA.,Department of Psychology, University of Oslo, Norway
| | - H H Krämer
- Department of Neurology, Justus Liebig University, Giessen, Germany
| | - L C Lundblad
- Institute of Neuroscience and Physiology, University of Gothenburg, Sweden
| | - S S Nagi
- Center for Social and Affective Neuroscience, Linköping University, Sweden.,School of Medicine, Western Sydney University, NSW, Australia
| | - S Leknes
- Institute of Neuroscience and Physiology, University of Gothenburg, Sweden.,Department of Psychology, University of Oslo, Norway
| | - H Olausson
- Institute of Neuroscience and Physiology, University of Gothenburg, Sweden.,Center for Social and Affective Neuroscience, Linköping University, Sweden
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24
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Chelnokova O, Laeng B, Løseth G, Eikemo M, Willoch F, Leknes S. The µ-opioid system promotes visual attention to faces and eyes. Soc Cogn Affect Neurosci 2016; 11:1902-1909. [PMID: 27531386 DOI: 10.1093/scan/nsw116] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 07/17/2016] [Accepted: 08/10/2016] [Indexed: 12/25/2022] Open
Abstract
Paying attention to others' faces and eyes is a cornerstone of human social behavior. The µ-opioid receptor (MOR) system, central to social reward-processing in rodents and primates, has been proposed to mediate the capacity for affiliative reward in humans. We assessed the role of the human MOR system in visual exploration of faces and eyes of conspecifics. Thirty healthy males received a novel, bidirectional battery of psychopharmacological treatment (an MOR agonist, a non-selective opioid antagonist, or placebo, on three separate days). Eye-movements were recorded while participants viewed facial photographs. We predicted that the MOR system would promote visual exploration of faces, and hypothesized that MOR agonism would increase, whereas antagonism decrease overt attention to the information-rich eye region. The expected linear effect of MOR manipulation on visual attention to the stimuli was observed, such that MOR agonism increased while antagonism decreased visual exploration of faces and overt attention to the eyes. The observed effects suggest that the human MOR system promotes overt visual attention to socially significant cues, in line with theories linking reward value to gaze control and target selection. Enhanced attention to others' faces and eyes represents a putative behavioral mechanism through which the human MOR system promotes social interest.
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Affiliation(s)
- Olga Chelnokova
- Department of Psychology, University of Oslo, Oslo N-0317, Norway
| | - Bruno Laeng
- Department of Psychology, University of Oslo, Oslo N-0317, Norway
| | - Guro Løseth
- Department of Psychology, University of Oslo, Oslo N-0317, Norway
| | - Marie Eikemo
- Department of Psychology, University of Oslo, Oslo N-0317, Norway.,Norwegian Center for Addiction Research, University of Oslo, Oslo N-0318, Norway.,Division of Mental Health and Addiction, Oslo University Hospital, Oslo N-0318, Norway
| | - Frode Willoch
- Department of Medicine, University of Oslo, Oslo N-0316, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Oslo N-0317, Norway.,Department of Medicine, University of Oslo, Oslo N-0316, Norway.,The Intervention Centre, Oslo University Hospital, Oslo N-0424, Norway
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25
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Nilsen AS, Blix I, Leknes S, Ekeberg Ø, Skogstad L, Endestad T, Østberg BC, Heir T. Brain Activity in Response to Trauma-specific, Negative, and Neutral Stimuli. A fMRI Study of Recent Road Traffic Accident Survivors. Front Psychol 2016; 7:1173. [PMID: 27547195 PMCID: PMC4974943 DOI: 10.3389/fpsyg.2016.01173] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 07/25/2016] [Indexed: 11/13/2022] Open
Abstract
Most studies of neuro-functional patterns in trauma-exposed individuals have been conducted considerable time after the traumatic event. Hence little is known about neuro-functional processing shortly after trauma-exposure. We investigated brain activity patterns in response to trauma reminders as well as neutral and negative stimuli in individuals who had recently (within 3 weeks) been involved in a road traffic accident (RTA). Twenty-three RTA survivors and 17 non-trauma-exposed healthy controls (HCs) underwent functional MRI while viewing Trauma-specific, Negative, and Neutral pictures. Data were analyzed from four a priori regions of interest, including bilateral amygdala, subcallosal cortex, and medial prefrontal cortex. In addition, we performed a whole brain analysis and functional connectivity analysis during stimulus presentation. For both groups, Negative stimuli elicited more activity in the amygdala bilaterally than did Neutral and Trauma-specific stimuli. The whole brain analysis revealed higher activation in sensory processing related areas (bilateral occipital and temporal cortices and thalamus) as well as frontal and superior parietal areas, for the RTA group compared to HC, for Trauma-specific stimuli contrasted with Neutral stimuli. We also observed higher functional connectivity for Trauma-specific stimuli, between bilateral amygdala and somatosensory areas, for the RTA group compared to controls, when contrasted with Neutral stimuli. We argue that these results might indicate an attentional sensory processing bias toward Trauma-specific stimuli for trauma exposed individuals, a result in line with findings from the post-traumatic stress disorder literature.
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Affiliation(s)
- Andre S Nilsen
- Norwegian Centre for Violence and Traumatic Stress StudiesOslo, Norway; Center for the Study of Human Cognition, Department of Psychology, University of OsloOslo, Norway
| | - Ines Blix
- Norwegian Centre for Violence and Traumatic Stress Studies Oslo, Norway
| | - Siri Leknes
- Center for the Study of Human Cognition, Department of Psychology, University of OsloOslo, Norway; The Intervention Centre, Oslo University HospitalOslo, Norway
| | - Øivind Ekeberg
- Division of Mental Health and Addiction, Oslo University HospitalOslo, Norway; Department of Behavioral Sciences in Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of OsloOslo, Norway
| | - Laila Skogstad
- Research and Development, Department of Acute Medicine, Oslo University Hospital Oslo, Norway
| | - Tor Endestad
- Center for the Study of Human Cognition, Department of Psychology, University of Oslo Oslo, Norway
| | | | - Trond Heir
- Norwegian Centre for Violence and Traumatic Stress StudiesOslo, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of OsloOslo, Norway
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26
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Ellingsen DM, Leknes S, Løseth G, Wessberg J, Olausson H. The Neurobiology Shaping Affective Touch: Expectation, Motivation, and Meaning in the Multisensory Context. Front Psychol 2016; 6:1986. [PMID: 26779092 PMCID: PMC4701942 DOI: 10.3389/fpsyg.2015.01986] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/12/2015] [Indexed: 01/01/2023] Open
Abstract
Inter-individual touch can be a desirable reward that can both relieve negative affect and evoke strong feelings of pleasure. However, if other sensory cues indicate it is undesirable to interact with the toucher, the affective experience of the same touch may be flipped to disgust. While a broad literature has addressed, on one hand the neurophysiological basis of ascending touch pathways, and on the other hand the central neurochemistry involved in touch behaviors, investigations of how external context and internal state shapes the hedonic value of touch have only recently emerged. Here, we review the psychological and neurobiological mechanisms responsible for the integration of tactile “bottom–up” stimuli and “top–down” information into affective touch experiences. We highlight the reciprocal influences between gentle touch and contextual information, and consider how, and at which levels of neural processing, top-down influences may modulate ascending touch signals. Finally, we discuss the central neurochemistry, specifically the μ-opioids and oxytocin systems, involved in affective touch processing, and how the functions of these neurotransmitters largely depend on the context and motivational state of the individual.
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Affiliation(s)
- Dan-Mikael Ellingsen
- MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical SchoolBoston, MA, USA; Department of Psychology, University of OsloOslo, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo Oslo, Norway
| | - Guro Løseth
- Department of Psychology, University of Oslo Oslo, Norway
| | - Johan Wessberg
- Institute of Neuroscience and Physiology, University of Gothenburg Gothenburg, Sweden
| | - Håkan Olausson
- Department of Clinical and Experimental Medicine, Linköping University Linköping, Sweden
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27
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Abstract
Social mammals engage in affiliative interactions both when seeking relief from negative affect and when searching for pleasure and joy. These two motivational states are both modulated by μ-opioid transmission. The μ-opioid receptor (MOR) system in the brain mediates pain relief and reward behaviors, and is implicated in social reward processing and affiliative bonding across mammalian species. However, pharmacological manipulation of the μ-opioid system has yielded opposite effects on rodents and primates: in rodents, social motivation is generally increased by MOR agonists and reduced by antagonists, whereas the opposite pattern has been shown in primates. Here, we address this paradox by taking into account differences in motivational state. We first review evidence for μ-opioid mediation of reward processing, emotion regulation, and affiliation in humans, non-human primates, rodents and other species. Based on the consistent cross-species similarities in opioid functioning, we propose a unified, state-dependent model for μ-opioid modulation of affiliation across the mammalian species. Finally, we show that this state-dependent model is supported by evidence from both rodent and primate studies, when species and age differences in social separation response are taken into account.
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Affiliation(s)
- Guro E. Loseth
- Department of Psychology, University of OsloOslo, Norway
| | | | - Siri Leknes
- Department of Psychology, University of OsloOslo, Norway
- The Intervention Centre, Oslo University HospitalOslo, Norway
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28
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Chelnokova O, Laeng B, Eikemo M, Riegels J, Løseth G, Maurud H, Willoch F, Leknes S. Rewards of beauty: the opioid system mediates social motivation in humans. Mol Psychiatry 2014; 19:746-7. [PMID: 24514570 DOI: 10.1038/mp.2014.1] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- O Chelnokova
- Department of Psychology, University of Oslo, Oslo, Norway
| | - B Laeng
- Department of Psychology, University of Oslo, Oslo, Norway
| | - M Eikemo
- Department of Psychology, University of Oslo, Oslo, Norway
| | - J Riegels
- Department of Psychology, University of Oslo, Oslo, Norway
| | - G Løseth
- Department of Psychology, University of Oslo, Oslo, Norway
| | - H Maurud
- Department of Psychology, University of Oslo, Oslo, Norway
| | - F Willoch
- Department of Medicine, University of Oslo, Oslo, Norway
| | - S Leknes
- 1] Department of Psychology, University of Oslo, Oslo, Norway [2] Department of Medicine, University of Oslo, Oslo, Norway
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29
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Abstract
Pain is mostly thought of as a problem-as debilitating or harmful. Despite its unpleasantness, however, under some conditions pain can be associated with positive consequences. In this review, we explore these positive biological, psychological, and social consequences of pain. We highlight three different domains in which pain may be considered to have positive consequences. First, pain facilitates pleasure by providing an important contrast for pleasurable experiences, increasing sensitivity to sensory input, and facilitating self-rewarding behavior. Second, pain augments self-regulation and enhancement by increasing cognitive control, reducing rumination, and demonstrating virtue. Third, pain promotes affiliation by arousing empathy from others, motivating social connection, and enhancing group formation. Drawing on evidence scattered across a range of academic fields, we provide for reflection on how pain is represented, generate insights into pain-seeking behavior, and draw attention to the role of painful experiences in maximizing positive outcomes.
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30
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31
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32
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Ellingsen DM, Wessberg J, Chelnokova O, Olausson H, Laeng B, Leknes S. In touch with your emotions: oxytocin and touch change social impressions while others' facial expressions can alter touch. Psychoneuroendocrinology 2014; 39:11-20. [PMID: 24275000 DOI: 10.1016/j.psyneuen.2013.09.017] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 09/13/2013] [Accepted: 09/14/2013] [Indexed: 11/15/2022]
Abstract
Interpersonal touch is frequently used for communicating emotions, strengthen social bonds and to give others pleasure. The neuropeptide oxytocin increases social interest, improves recognition of others' emotions, and it is released during touch. Here, we investigated how oxytocin and gentle human touch affect social impressions of others, and vice versa, how others' facial expressions and oxytocin affect touch experience. In a placebo-controlled crossover study using intranasal oxytocin, 40 healthy volunteers viewed faces with different facial expressions along with concomitant gentle human touch or control machine touch, while pupil diameter was monitored. After each stimulus pair, participants rated the perceived friendliness and attractiveness of the faces, perceived facial expression, or pleasantness and intensity of the touch. After intranasal oxytocin treatment, gentle human touch had a sharpening effect on social evaluations of others relative to machine touch, such that frowning faces were rated as less friendly and attractive, whereas smiling faces were rated as more friendly and attractive. Conversely, smiling faces increased, whereas frowning faces reduced, pleasantness of concomitant touch - the latter effect being stronger for human touch. Oxytocin did not alter touch pleasantness. Pupillary responses, a measure of attentional allocation, were larger to human touch than to equally intense machine touch, especially when paired with a smiling face. Overall, our results point to mechanisms important for human affiliation and social bond formation.
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Affiliation(s)
- Dan-Mikael Ellingsen
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-413 45 Gothenburg, Sweden; Department of Psychology, University of Oslo, 0317 Oslo, Norway.
| | - Johan Wessberg
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-413 45 Gothenburg, Sweden
| | - Olga Chelnokova
- Department of Psychology, University of Oslo, 0317 Oslo, Norway
| | - Håkan Olausson
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-413 45 Gothenburg, Sweden
| | - Bruno Laeng
- Department of Psychology, University of Oslo, 0317 Oslo, Norway
| | - Siri Leknes
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, S-413 45 Gothenburg, Sweden; Department of Psychology, University of Oslo, 0317 Oslo, Norway
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33
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Leknes S, Berna C, Lee MC, Snyder GD, Biele G, Tracey I. Response to the commentary "multiple potential mechanisms for context effects on pain". Pain 2013; 154:1485-1486. [PMID: 23726676 DOI: 10.1016/j.pain.2013.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 04/02/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Siri Leknes
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences (Nuffield Division of Anaesthetics), University of Oxford, Oxford OX3 9DU, UK Department of Psychology, University of Osl, 0317 Oslo, Norway
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Leknes S, Berna C, Lee MC, Snyder GD, Biele G, Tracey I. The importance of context: when relative relief renders pain pleasant. Pain 2012; 154:402-410. [PMID: 23352758 PMCID: PMC3590449 DOI: 10.1016/j.pain.2012.11.018] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 11/09/2012] [Accepted: 11/28/2012] [Indexed: 11/20/2022]
Abstract
Context can influence the experience of any event. For instance, the thought that "it could be worse" can improve feelings towards a present misfortune. In this study we measured hedonic feelings, skin conductance, and brain activation patterns in 16 healthy volunteers who experienced moderate pain in two different contexts. In the "relative relief context," moderate pain represented the best outcome, since the alternative outcome was intense pain. However, in the control context, moderate pain represented the worst outcome and elicited negative hedonic feelings. The context manipulation resulted in a "hedonic flip," such that moderate pain elicited positive hedonics in the relative relief context. Somewhat surprisingly, moderate pain was even rated as pleasant in this context, despite being reported as painful in the control context. This "hedonic flip" was corroborated by physiological and functional neuroimaging data. When moderate pain was perceived as pleasant, skin conductance and activity in insula and dorsal anterior cingulate were significantly attenuated relative to the control moderate stimulus. "Pleasant pain" also increased activity in reward and valuation circuitry, including the medial orbitofrontal and ventromedial prefrontal cortices. Furthermore, the change in outcome hedonics correlated with activity in the periacqueductal grey (PAG) of the descending pain modulatory system (DPMS). The context manipulation also significantly increased functional connectivity between reward circuitry and the PAG, consistent with a functional change of the DPMS due to the altered motivational state. The findings of this study point to a role for brainstem and reward circuitry in a context-induced "hedonic flip" of pain.
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Affiliation(s)
- Siri Leknes
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences (Nuffield Division of Anaesthetics), University of Oxford, Oxford OX3 9DU, UK
- Department of Psychology, University of Oslo, 0317 Oslo, Norway
- Corresponding author at: Department of Psychology, University of Oslo, Postboks 1094, Blindern, Oslo 0317, Norway.
| | - Chantal Berna
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences (Nuffield Division of Anaesthetics), University of Oxford, Oxford OX3 9DU, UK
| | - Michael C. Lee
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences (Nuffield Division of Anaesthetics), University of Oxford, Oxford OX3 9DU, UK
| | - Gregory D. Snyder
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences (Nuffield Division of Anaesthetics), University of Oxford, Oxford OX3 9DU, UK
| | - Guido Biele
- Department of Psychology, University of Oslo, 0317 Oslo, Norway
| | - Irene Tracey
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences (Nuffield Division of Anaesthetics), University of Oxford, Oxford OX3 9DU, UK
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35
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Wanigasekera V, Lee MC, Rogers R, Kong Y, Leknes S, Andersson J, Tracey I. Baseline reward circuitry activity and trait reward responsiveness predict expression of opioid analgesia in healthy subjects. Proc Natl Acad Sci U S A 2012; 109:17705-10. [PMID: 23045652 PMCID: PMC3491480 DOI: 10.1073/pnas.1120201109] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Variability in opioid analgesia has been attributed to many factors. For example, genetic variability of the μ-opioid receptor (MOR)-encoding gene introduces variability in MOR function and endogenous opioid neurotransmission. Emerging evidence suggests that personality trait related to the experience of reward is linked to endogenous opioid neurotransmission. We hypothesized that opioid-induced behavioral analgesia would be predicted by the trait reward responsiveness (RWR) and the response of the brain reward circuitry to noxious stimuli at baseline before opioid administration. In healthy volunteers using functional magnetic resonance imaging and the μ-opioid agonist remifentanil, we found that the magnitude of behavioral opioid analgesia is positively correlated with the trait RWR and predicted by the neuronal response to painful noxious stimuli before infusion in key structures of the reward circuitry, such as the orbitofrontal cortex, nucleus accumbens, and the ventral tegmental area. These findings highlight the role of the brain reward circuitry in the expression of behavioral opioid analgesia. We also show a positive correlation between behavioral opioid analgesia and opioid-induced suppression of neuronal responses to noxious stimuli in key structures of the descending pain modulatory system (amygdala, periaqueductal gray, and rostral-ventromedial medulla), as well as the hippocampus. Further, these activity changes were predicted by the preinfusion period neuronal response to noxious stimuli within the ventral tegmentum. These results support the notion of future imaging-based subject-stratification paradigms that can guide therapeutic decisions.
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Affiliation(s)
- Vishvarani Wanigasekera
- Centre for Functional Magnetic Resonance Imaging of the Brain, Nuffield Department of Clinical Neurosciences, Nuffield Division of Anaesthetics, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DU, United Kingdom.
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36
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Leknes S, Wessberg J, Ellingsen DM, Chelnokova O, Olausson H, Laeng B. Oxytocin enhances pupil dilation and sensitivity to 'hidden' emotional expressions. Soc Cogn Affect Neurosci 2012; 8:741-9. [PMID: 22648957 DOI: 10.1093/scan/nss062] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Sensing others' emotions through subtle facial expressions is a highly important social skill. We investigated the effects of intranasal oxytocin treatment on the evaluation of explicit and 'hidden' emotional expressions and related the results to individual differences in sensitivity to others' subtle expressions of anger and happiness. Forty healthy volunteers participated in this double-blind, placebo-controlled crossover study, which shows that a single dose of intranasal oxytocin (40 IU) enhanced or 'sharpened' evaluative processing of others' positive and negative facial expression for both explicit and hidden emotional information. Our results point to mechanisms that could underpin oxytocin's prosocial effects in humans. Importantly, individual differences in baseline emotional sensitivity predicted oxytocin's effects on the ability to sense differences between faces with hidden emotional information. Participants with low emotional sensitivity showed greater oxytocin-induced improvement. These participants also showed larger task-related pupil dilation, suggesting that they also allocated the most attentional resources to the task. Overall, oxytocin treatment enhanced stimulus-induced pupil dilation, consistent with oxytocin enhancement of attention towards socially relevant stimuli. Since pupil dilation can be associated with increased attractiveness and approach behaviour, this effect could also represent a mechanism by which oxytocin increases human affiliation.
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Affiliation(s)
- Siri Leknes
- Department of Psychology, University of Oslo, Postboks 1094, Blindern 0317, Oslo, Norway.
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37
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Leknes S. The pain modulatory cocktail. Scand J Pain 2011; 2:105-107. [DOI: 10.1016/j.sjpain.2011.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Siri Leknes
- University of Oslo , Forskningsveien 3A, Postboks 1094 Blindern , Oslo , Norway
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Abstract
Relief fits the definition of a reward. Unlike other reward types the pleasantness of relief depends on the violation of a negative expectation, yet this has not been investigated using neuroimaging approaches. We hypothesized that the degree of negative expectation depends on state (dread) and trait (pessimism) sensitivity. Of the brain regions that are involved in mediating pleasure, the nucleus accumbens also signals unexpected reward and positive prediction error. We hypothesized that accumbens activity reflects the level of negative expectation and subsequent pleasant relief. Using fMRI and two purpose-made tasks, we compared hedonic and BOLD responses to relief with responses during an appetitive reward task in 18 healthy volunteers. We expected some similarities in task responses, reflecting common neural substrates implicated across reward types. However, we also hypothesized that relief responses would differ from appetitive rewards in the nucleus accumbens, since only relief pleasantness depends on negative expectations. The results confirmed these hypotheses. Relief and appetitive reward task activity converged in the ventromedial prefrontal cortex, which also correlated with appetitive reward pleasantness ratings. In contrast, dread and pessimism scores correlated with relief but not with appetitive reward hedonics. Moreover, only relief pleasantness covaried with accumbens activation. Importantly, the accumbens signal appeared to specifically reflect individual differences in anticipation of the adverse event (dread, pessimism) but was uncorrelated to appetitive reward hedonics. In conclusion, relief differs from appetitive rewards due to its reliance on negative expectations, the violation of which is reflected in relief-related accumbens activation.
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Affiliation(s)
- Siri Leknes
- Nuffield Division of Anaesthetics, Nuffield Department of Clinical Neurosciences, Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), University of Oxford, Oxford, Oxfordshire, United Kingdom.
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Berna C, Leknes S, Holmes EA, Edwards RR, Goodwin GM, Tracey I. Induction of depressed mood disrupts emotion regulation neurocircuitry and enhances pain unpleasantness. Biol Psychiatry 2010; 67:1083-90. [PMID: 20303069 DOI: 10.1016/j.biopsych.2010.01.014] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2009] [Revised: 01/07/2010] [Accepted: 01/10/2010] [Indexed: 11/26/2022]
Abstract
BACKGROUND Depressed mood alters the pain experience. Yet, despite its clear clinical relevance, little is known about the cognitive and neural mechanisms underlying this phenomenon. We tested an experimental manipulation to unravel the interaction between depressed mood and pain. We hypothesized that dysregulation of the neural circuitry underlying emotion regulation is the mechanism whereby pain processing is affected during depressed mood. METHODS Using functional magnetic resonance imaging, we compared the effects of sad and neutral cognitive mood inductions on affective pain ratings, pain-specific cognitions, and central pain processing of a tonic noxious heat stimulus in 20 healthy volunteers. RESULTS The increase in negative pain-specific cognitions during depressed mood predicted the perceived increase in pain unpleasantness. Following depressed mood induction, brain responses to noxious thermal stimuli were characterized by increased activity in a broad network including prefrontal areas, subgenual anterior cingulate cortex, and hippocampus, as well as significantly less deactivation when compared with pain responses in a neutral mood. The participants who reported the largest increase in pain unpleasantness after the sad mood induction showed greater inferior frontal gyrus and amygdala activation, linking changes in emotion regulation mechanisms with enhancement of pain affect. CONCLUSIONS Our results inform how depressed mood and chronic pain co-occur clinically and may serve to develop and translate effective interventions using pharmacological or psychological treatment.
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Affiliation(s)
- Chantal Berna
- Centre for Functional Magnetic Resonance Imaging of the Brain, Department of Clinical Neurology, University of Oxford, Oxford, United Kingdom.
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Abstract
Relief from pain in humans is frequently measured by computing the reduction on an 11-point pain intensity scale. However, this definition of relief may be insufficient to capture the utility of pain relief for the individual. Based on pain literature and evidence from studies examining relief and reward, it is clear that pain relief is a broad concept comprising several factors, only one of which is pain intensity reduction. According to opponent process theory, all sensations consist of a primary process and a slow 'opponent process' of opposite valence, the purpose of which is to reduce the deviation from homeostatic balance. Here, opponent process theory provided a framework to explore the interaction between pain, relief and reward. We devised three psychophysical studies examining the temporal (Experiment I) and magnitude (Experiments I and II) relationships between pain severity and its subsequent relief. In Experiment III, we further manipulated the magnitude and pleasantness of relief experienced by applying innocuous cooling following noxious heat stimulation of capsaicin-sensitized skin. Results confirmed predictions from opponent process theory and showed that pain intensity reduction was significantly stronger than relief intensity ratings. Furthermore, continuous relief ratings appeared to reflect the speed of pain intensity reduction. Varying pain intensity parametrically confirmed that relief increases with pain intensity. That innocuous cooling following primary hyperalgesia intervention significantly increased the intensity, pleasantness and duration of relief provides further evidence that pain relief encapsulates more than a reduction in pain intensity. Importantly, the high relief pleasantness ratings confirmed the hypothesized link between relief and reward.
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Affiliation(s)
- Siri Leknes
- Oxford Centre for Functional MRI of the Brain, Clinical Neurology and Nuffield Department of Anaesthetics, Oxford University, John Radcliffe Hospital, Oxford, UK.
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Abstract
Pain and pleasure are powerful motivators of behaviour and have historically been considered opposites. Emerging evidence from the pain and reward research fields points to extensive similarities in the anatomical substrates of painful and pleasant sensations. Recent molecular-imaging and animal studies have demonstrated the important role of the opioid and dopamine systems in modulating both pain and pleasure. Understanding the mutually inhibitory effects that pain and reward processing have on each other, and the neural mechanisms that underpin such modulation, is important for alleviating unnecessary suffering and improving well-being.
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Affiliation(s)
- Siri Leknes
- Oxford Centre for Functional MRI of the Brain, Department of Clinical Neurology, Oxford University, John Radcliffe Hospital, Oxford, OX3 9DU, UK
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