疼痛恐惧的形成及其对疼痛知觉的影响

脑岛、杏仁核是疼痛恐惧形成的重要神经网络中心。疼痛恐惧增强了慢性疼痛患者的疼痛知觉体验, 进而加剧抑郁、焦虑情绪和功能损伤程度。脑岛、杏仁核、前额皮层和前扣带回是疼痛恐惧影响疼痛知觉的重要神经基础。通过认知方法干预疼痛恐惧可以改善患者的抑郁、焦虑情绪, 减少功能损伤。未来研究应拓展疼痛恐惧的测量工具, 采用功能磁共振成像技术进一步揭示疼痛恐惧影响慢性疼痛患者疼痛知觉的神经机制。     

Mothers' facial expressions of pain and fear and infants' pain response during immunization

The goal of the current study was to examine the relationship between mothers' spontaneous facial expressions of pain and fear immediately preceding their infants' immunizations and infants' facial expressions of pain immediately following immunizations. Infants' observations of mothers' faces prior to immunization also were examined to explore whether these observations moderated the effect of mothers' facial expressions on infant pain. The final sample included 58 mothers and their infants. Video data were used to code maternal facial expressions, infants' observations, and infants' expressions of pain. Infants who observed their mothers' faces had mothers who expressed significantly more fear pre‐needle. Furthermore, mothers' facial expressions of mild fear pre‐needle were associated with lower levels of infants' pain expression post‐needle. A regression analysis confirmed maternal facial expressions of mild fear pre‐needle as the strongest predictor of infant pain post‐needle after controlling for infants' observations of mothers' faces. Mothers' subtle facial expressions of fear may indicate a relationship history of empathic caregiving that functions to support infants' abilities to regulate distress following painful procedures. Interventions aimed at improving caregiver sensitivity to infants' emotional cues may prove beneficial to infants in pain. Future directions in research are discussed.     

Effects of pain acceptance and pain control strategies on physical impairment in individuals with chronic low back pain

Psychosocial treatments for chronic pain are effective. There is a need, however, to understand the processes involved in determining how these treatments contribute to behavior change. Control and acceptance strategies represent two potentially important processes involved in treatment, although they differ significantly in approach. Results from laboratory-based studies suggest that acceptance-oriented strategies significantly enhance pain tolerance and behavioral persistence, compared with control-oriented strategies. There is a need, however, to investigate processes of acceptance and control directly in clinical settings. The present study investigated the effects of three brief instructional sets (pain control, pain acceptance, continued practice) on demonstrated physical impairment in 74 individuals with chronic low back pain using an analogue experimental design. After controlling for baseline performance, the pain acceptance group demonstrated greater overall functioning on a set of 7 standardized physical tasks relative to the other two groups, which did not differ from one another. Further, the acceptance group exhibited a 16.3% improvement in impairment, whereas the pain control group worsened by 8.3% and the continued practice group improved by 2.5%. These results suggest that acceptance may be a key process involved in behavior change in individuals with chronic pain.     

The effects of incorrect pain expectations on acquired fear and pain responses

Previous experimental research on the effects of incorrect intensity expectations of aversive events can be criticized because intensity expectations were not manipulated independently from changes in objective intensity. The present study aims at investigating the effects of incorrect intensity expectations on the immediate and later responses to a painful stimulus, and on the acquisition of anticipatory responses, with proper experimental control. Subjects (n = 62) received 20 painful stimuli of varying intensity. In the control group intensities were correctly signalled on all trials by an analogue signal. On 3 trials the signal was too large in the overprediction condition, and too small in the underestimation condition. Underpredicted painful experiences were related to subsequent higher pain responses on the physiological level, but not on the subjective level; and to increased anticipatory responses (increased pain expectations, uncertainty, subjective fear, skin conductance responses). Skin conductance level also indicated increased fear after underpredicted experiences. Overpredicted painful experiences were related to a faster decrease in subjective fear compared to the control group, but did not influence other variables. The findings support the notion that underpredictions contribute to the acquistion of fear and disrupt habituation processes. The asymmetrical processing of the two kinds of incorrectly predicted experiences is discussed.     

Cognitive differentiation, back pain, and psychogenic pain drawings

Two groups of subjects with back pain were studied (n = 67). All subjects underwent a battery of psychological tests which included a test of psychological differentiation (the Rod-and-Frame Test), a test of psychological defenses (Meta-contrast Technique), and the Eysenck Personality Inventory. In addition, the subjects drew a pain picture and answered a questionnaire on pain-related issues. Each group of subjects was then subdivided into 4 groups depending on the judged abnormality of their pain drawings. The two main groups were compared overall and the subgroups of the two back-pain groups compared with each other. The Meta-contrast Technique results show that depression was quite common among back-pain subjects as a whole compared to a painless group of subjects. Differences were found on field-dependence; subjects with abnormal pain drawings were more field-dependent than those with "normal" pain drawings. Few other between-group statistical differences were noted between the two back-pain groups. Expected scores on hysteria were not noted among the abnormal drawing makers, neither were there differences between the groups on the items of pain duration, physical functionings, or of depression.     

Hypnosis and clinical pain

Hypnosis has been demonstrated to reduce analogue pain, and studies on the mechanisms of laboratory pain reduction have provided useful applications to clinical populations. Studies showing central nervous system activity during hypnotic procedures offer preliminary information concerning possible physiological mechanisms of hypnotic analgesia. Randomized controlled studies with clinical populations indicate that hypnosis has a reliable and significant impact on acute procedural pain and chronic pain conditions. Methodological issues of this body of research are discussed, as are methods to better integrate hypnosis into comprehensive pain treatment.     

Pain intensity and pain unpleasantness in triathletes: A study examining their associations with pain catastrophizing and pain expectations

ObjectiveTriathletes represent a growing and unique population of individuals willing to endure significant mental and physical stress to practice the sport they love. However, little is known about the pain experienced while training for and competing in a triathlon and how psychological factors influence this experience. This study will assess pain experienced by triathletes in training and competition, and investigate the association between pain catastrophizing and pain expectations with triathlon pain intensity and pain unpleasantness.DesignIn this observational study, a sample of 261 triathletes completed two online surveys before and after participating in a triathlon.ResultsModerate levels of pain intensity and pain unpleasantness were reported during training and competition. Pain catastrophizing was positively associated with expected and actual triathlon pain unpleasantness, but not with pain intensity. Expected pain intensity was also significantly associated with pain intensity experienced while competing, whereas expected pain unpleasantness was significantly related to both triathlon pain intensity and unpleasantness. Finally, regression analysis revealed pain catastrophizing and pain expectations to be unique predictors of triathlon pain intensity and pain unpleasantness.ConclusionThis study highlights the important role of psychological factors in triathletes' experience of pain and could eventually help tailor interventions aimed at improving the practice of triathlon.     

Conceptualizing suffering and pain

Background

This article aims to contribute to a better conceptualization of pain and suffering by providing non-essential and non-naturalistic definitions of both phenomena. Contributions of classical evidence-based medicine, the humanistic turn in medicine, as well as the phenomenology and narrative theories of suffering and pain, together with certain conceptions of the person beyond them (the mind-body dichotomy, Cassel’s idea of persons as “intact beings”) are critically discussed with such purpose.

Methods

A philosophical methodology is used, based on the review of existent literature on the topic and the argumentation in favor of what are found as better definitions of suffering and pain.

Results

Pain can be described in neurological terms but cognitive awareness, interpretation, behavioral dispositions, as well as cultural and educational factors have a decisive influence on pain perception. Suffering is proposed to be defined as an unpleasant or even anguishing experience, severely affecting a person at a psychophysical and existential level. Pain and suffering are considered unpleasant. However, the provided definitions neither include the idea that pain and suffering can attack and even destroy the self nor the idea that they can constructively expand the self; both perspectives can b e equally useful for managing pain and suffering, but they are not defining features of the same. Including the existential dimension in the definition of suffering highlights the relevance of suffering in life and its effect on one’s own attachment to the world (including personal management, or the cultural and social influences which shape it). An understanding of pain and suffering life experiences is proposed, meaning that they are considered aspects of a person’s life, and the self is the ever-changing sum of these (and other) experiences.

Conclusions

The provided definitions will be useful to the identification of pain and suffering, to the discussion of how to relieve them, and to a better understanding of how they are expressed and experienced. They lay the groundwork for further research in all these areas, with the twofold aim of a) avoiding epistemological mistakes and moral injustices, and b) highlighting the limitations of medicine in the treatment of suffering and pain.

     

God and animal pain

It seems that animal pain is an obstacle to belief in a good God, though Christianity has not been much concerned with the issue. A systemic approach to pain is not a complete answer, nor is there any merit in denying that God is subject to moral appraisal. Marilyn McCord Adams recommends that such investigations be located in the specifics of a religious tradition. Her advice eliminates a couple of radical solutions but there appear to be a number of ways in which progress might be made without doing violence to the tradition that is in need of a theodicy.     

Energy and psychical pain

Several relationships between energy and psychical pain are developed in this paper. These concepts are a-structural and existential in spirit, although developed in the framework of some analytic formulations on personality. A key concept developed is that the nature of psychical pain is determined, in part, by the manner in which the state of psychical energy associated with the pain departs from a given healthy ideal.     

Pain and pain perception

Pain is both sensual perception and sense of touch, and it leads to emotional change of health, which has an effect back to a pain perception. Experience of pain is modified by intern and extern influences, and it can appear very multiformly in the chronicity. A part of these factors are described.     

Beautiful faces in pain: Biases and accuracy in the perception of pain

Abstract

The impact of appearance-based information on judgments about the psychological functioning of pain patients was investigated. Video-tapes of low back pain patients experiencing pain were used as stimulus materials. Subjects viewed silent video clips and photographs of the patients' faces and made judgments about the functioning of these patients. These judgments were affected both by patient physical attractiveness and gender. Physically attractive patients and male patients were judged to be functioning better than physically unattractive and female patients. The judgments were reasonably described as biased because the perceived differences about patients varying in attractiveness and sex were not associated with measures of actual patient functioning.     

Effects of anger suppression on pain severity and pain behaviors among chronic pain patients: evaluation of an ironic process model

OBJECTIVE: Evidence for links between anger inhibition or suppression and chronic pain severity is based mostly on studies with correlation designs. Following from ironic process theory, we proposed that attempts to suppress angry thoughts during provocation would increase subsequent pain intensity among chronic low back pain (CLBP) patients, and do so through paradoxically enhanced accessibility of anger. DESIGN: CLBP patients (N = 58) were assigned to suppression and nonsuppression conditions while performing a computer maze task with a harassing confederate. A structured pain behavior task (SPBT) followed. MAIN OUTCOME MEASURES: Self-reported anger, anxiety, and sadness following maze task. Self-reported pain severity and number of observed pain behaviors during SPBT. RESULTS: Patients told to suppress during provocation: (a) reported greater anger following the maze task, reported greater pain intensity during the SPBT, and exhibited more pain behaviors than patients not suppressing; (b) postmaze anger levels significantly mediated group differences on pain behaviors. CONCLUSION: Attempts by CLBP patients to suppress anger may aggravate pain related to their clinical condition through ironically increased feelings of anger.     

The impact of experiential avoidance on the relations between illness representations,pain catastrophising and pain interference in chronic pain

Objective: The aim of this study was to examine the effects of experiential avoidance (EA) on the indirect relationship of chronic pain patients’ illness representations to pain interference, through pain catastrophising

Design and main outcome measure: The sample consisted of 162 patients diagnosed with an arthritis-related or a musculoskeletal disorder. The effects of EA on the pathway between illness representations, pain catastrophising and pain interference were examined with PROCESS, a computational tool for SPSS

Results: After controlling for patient and illness-related variables and pain severity, the ‘illness representations–pain catastrophising–pain interference’ pathway was interrupted at the higher levels of EA. The reason was that, at the high levels of EA, either the relation of illness representations to pain catastrophising or the relation of pain catastrophising to pain interference was not statistically significant.

Conclusion: The findings indicate that EA is not a generalised negative response to highly aversive conditions, at least as far as the factors examined in this study are concerned. EA may rather reflect a coping reaction, the impact of which depends on its specific interactions with the other aspects of the self-regulation mechanism. At least in chronic pain, EA should become the focus of potential intervention only when its interaction with the illness-related self-regulation mechanism results in negative outcomes.