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Results for “Pain Perception”

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PubMed1999

A comparison of diffuse noxious inhibitory controls in men and women.

Results from clinical and experimental pain studies provide consistent evidence of sex differences in pain perception, with women reporting more clinical pain and demonstrating lower pain threshold and tolerance levels than men. The present study was designed to assess the notion that sex differences in pain perception may be related to differential activation of supraspinal pain modulation systems. Specifically, the phenomenon of diffuse noxious inhibitory controls (DNIC) was examined in healthy young adult men (n = 39) and women (n = 44) using repeated assessment of nociceptive flexion reflex activity before, during and after exposure to forearm ischemia. Consistent with previous research, women exhibited significantly lower nociceptive flexion reflex thresholds than men, and reported significantly greater pain in response to both forearm ischemia and repeated electrocutaneous stimulation required to elicit the nociceptive flexion reflex. Application of forearm ischemia was associated with a significant decrease in nociceptive flexion reflex activity in both men and women, however, the degree of attenuation of nociceptive flexion reflex activity was not significantly different between the sexes. These findings suggest that men and women exhibit similar activation of diffuse noxious inhibitory controls, but they do not exclude the possibility of sex differences in other forms of central pain modulation.

Adolescent↗

PubMed2002

Effects of low-dose ketamine on neuropathic pain: An electroencephalogram-electrooculogram/behavioral study.

The aim of the present study was to clarify the neurophysiological changes associated with analgesic and behavioral effects of low-dose ketamine HCl in patients suffering from chronic neuropathic pain. Ten in-patients with neuropathic pain participated in this single-blind, placebo-controlled study after giving written informed consent. Following intravenous injections of a saline solution (placebo), three bolus injections of 5 mg ketamine HCl were administered at 5 min intervals. Changes in pain perception were assessed using a numerical rating scale for pain. Behavioral changes, including psychotomimetic effects, were assessed using the Brief Psychiatric Rating Scale (BPRS). Electroencephalograms (EEG) and electrooculograms (EOG) were recorded continuously throughout the testing period. One minute EEG and closed-eye eye movements were quantified. The effects of ketamine were evaluated by comparing the neurophysiological and behavioral parameters obtained from the placebo and ketamine trials. Pain reduction was significantly correlated with ketamine-induced changes in hallucinatory behavior and excitement as measured by the BPRS. Ketamine injections caused a significant decrease in the EEGalpha amplitude without an accompanying reduction in EEG frequency. The EEGalpha amplitude reduction at the right central electrode was significantly related to subjective pain relief. Subanesthetic doses of ketamine significantly decreased rapid eye movements, but did not initiate slow eye movements. In conclusion, the present EEG-EOG/behavioral results indicate that ketamine-induced failure of neural integration between cortical-subcortical regions induces psychotic symptoms and alters pain perception on neuropathic pain.

Aged↗

PubMed2006

Is pain the price of empathy? The perception of others' pain in patients with congenital insensitivity to pain.

Empathy is a complex form of psychological inference that enables us to understand the personal experience of another person through cognitive/evaluative and affective processes. Recent findings suggest that empathy for pain may involve a 'mirror-matching' simulation of the affective and sensory features of others' pain. Despite such evidence for a shared representation of self and other pain at the neural level, the possible influence of the observer's own sensitivity to pain upon his perception of others' pain has not been investigated yet. The aim of this study was to explore how patients with congenital insensitivity to pain (CIP), who are largely deprived of common stimulus-induced pain experiences, perceive the pain of others. Ratings of verbally presented imaginary painful situations showed that CIP patients' semantic knowledge regarding the pain of others did not differ from control subjects. Moreover, the propensity to infer pain from facial expressions was very similar between CIP patients and control subjects. On the other hand, when asked to rate pain-inducing events seen in video clips in the absence of visible or audible pain-related behaviour, CIP patients showed more variable and significantly lower pain ratings, as well as a reduction in aversive emotional responses, compared with control subjects. Interestingly, pain judgements, inferred either from facial pain expressions or from pain-inducing events, were strongly related to inter-individual differences in emotional empathy among CIP patients, while such correlation between pain judgement and empathy was not found in control subjects. The results suggest that a normal personal experience of pain is not necessarily required for perceiving and feeling empathy for others' pain. In the absence of functional somatic resonance mechanisms shaped by previous pain experiences, others' pain might be greatly underestimated, however, especially when emotional cues are lacking, unless the observer is endowed with sufficient empathic abilities to fully acknowledge the suffering experience of others in spite of his own insensitivity.

Adolescent↗

PubMed2006

Judgments of pain in the neonatal intensive care setting: a survey of direct care staffs' perceptions of pain in infants at risk for neurological impairment.

OBJECTIVE: To determine whether healthcare professionals believe the pain of infants at risk for neurologic impairment differs from that of typical infants. SETTING: Neonatal intensive care units at 2 tertiary pediatric centers in Canada. PARTICIPANTS: Ninety-nine healthcare professionals who practice in the neonatal intensive care unit (51 nurses, 19 physicians, 18 respiratory therapists, 11 other). MAJOR MEASURES: Participants completed the Pain Opinion Questionnaire. It elicits beliefs regarding the similarity of the pain experienced by infants at mild, moderate, and severe risk for neurologic impairment relative to those without risk for neurologic impairment along 5 pain facets (ie, sensation, emotional reaction, behavioral reaction, communication, incidence). RESULTS: Pain Opinion Questionnaire scores varied by level of risk of neurologic impairment (mild, moderate, severe) and pain facet. Respondents believed infants with risk were overall less likely to experience pain similar to infants without risk as the level of risk increased [F(2,97) = 66.0, P < 0.001] and were more likely to have a reduced pain experience relative to infants without risk as the level of risk increased [F(2,97) = 62.2, P < 0.001]. Pain Opinion Questionnaire scores did not vary due to profession, experience, gender, or age. CONCLUSION: Professionals expressed the belief that neurologically impaired infants' pain experience is reduced, relative to infants without impairment, as their level of risk for neurologic impairment increases. This belief did not vary due to professional experience or personal factors. Future studies should investigate the source of these beliefs and their impact on the pain management provided to infants with risk for neurologic impairment.

Adult↗

PubMed2004

Separation effect and perception of pain and discomfort from two types of orthodontic separators.

AIM: To examine two types of orthodontic separators, focusing on the separating effect and patients' perception of pain and discomfort. METHODS: The separators tested were spring-type and elastomeric separators. Thirty teenagers participated, and all were scheduled for treatment with a fixed orthodontic appliance. Two spring-type and two elastomeric separators were placed alternately in the left or the right quadrant. After a separation period of 5 days, the amount of separation was measured with a leaf gauge. Nine questionnaires with visual analogue scales and questions with fixed answers were used to register the patient perceptions. RESULTS: The mean separation was 0.3 mm for the spring-type and 0.4 mm for the elastomeric separators (P < .05). The springs were considered less painful than the elastomerics, but the difference was not statistically significant. For both separators, the pain was worst at day 2 and subsided almost completely by day 5. Due to pain, 14 of the 30 patients changed their food habits, and 13 took analgesics. CONCLUSIONS: The separation effect of the two separators was considered clinically equivalent and since pain of moderate intensity occurs during the separation period, analgesics and soft food can be recommended.

Adolescent↗

PubMed1986

Postoperative TENS pain relief after knee surgery: objective evaluation.

A comparison was made between the pain-relieving effect of placebo-transcutaneous electrical nerve stimulation (TENS), high frequency TENS, and epidural analgesia with dilute local anesthetics in 15 patients with open knee surgery. Assessment of pain was compared with the patients' ability to contract their quadriceps muscle; the ability was measured with integrated EMG (IEMG) before and after the different treatments. The results showed that placebo-TENS had no significant effect on either pain perception or on IEMG. High frequency TENS given for 15 min to 20 min decreased pain perception by 50% at rest and by 11% after quadriceps contraction. High frequency TENS increased muscle contraction ability by 305%, compared with the initial contraction before treatment. Epidural injection of a dilute local anesthetic decreased pain perception by 90% at rest and by 67% after contraction, and increased muscle contraction ability by 1,846%. TENS undoubtedly has a place in the postoperative pain treatment, although its effect is not as strong as that of epidural analgesia with local anesthetics. TENS, however, is easy to administer, lacks side effects, and can be administered by the patients themselves.

Adult↗

PubMed2003

The relationship between chronic pain, immune function, depression, and health behaviors.

The objectives of this study were 1) to determine the relationships between pain perceptions, immune function, depression and health behaviors and 2) to examine the effects of chronic pain on immune function using depression and health behaviors as covariates. A nonexperimental cross-sectional design was used to compare 24 chronic back pain patients with 33 asymptomatic no-pain healthy subjects. Immune function measures using natural killer (NK) cell activity, percent and numbers of NK cells, and T-cell lymphocyte proliferation with mitogens concanavalin A (ConA) and pytohemagglutinin (PHA) as well as self-report measures for depression and health behaviors were collected on all subjects. Pain perceptions showed positive significant correlations with depression (P = 0.01) and total percent of NK cells (P = 0.04). Depression and health behaviors were negatively correlated (P = 0.01). Positive associations were observed for depression and 2 PHA mitogen levels (P < 0.05). Comparison of group means, controlling for depression and health behaviors, showed that chronic pain patients' immune function, as measured by the combined NK effector to target (E:T) cell ratio levels, was significantly higher than the no-pain comparison group. Pain perceptions may have a deleterious effect on enumerative NK cell measures and depression levels. However, people with chronic pain may not experience attenuation in functional immune parameters.

Adult↗

PubMed2007

Pain response in depersonalization: a functional imaging study using hypnosis in healthy subjects.

BACKGROUND: Depersonalization (DP) is characterized by persistent or recurrent episodes of detachment from one's self with reduced pain perception being a common feature. Alterations in the body schema similar to the cortico-limbic disconnection syndrome of pain asymbolia are suggested to be responsible for DP. In this study we used hypnosis to induce DP in healthy subjects and to examine neural patterns of pain perception in the state of DP by means of functional magnetic resonance imaging (fMRI). METHODS: Pain perception was investigated in 7 healthy subjects with high susceptibility to hypnosis in three different mental states: waking state (N-W), hypnotic relaxation (H-R) and hypnotic DP (H-DP). Pain was induced with electrical stimulation to the median nerve at the right wrist. fMRI measurements were performed during all states. RESULTS: Nociceptive stimuli led to an activation of the well described pain network including somatosensory and insular regions and the cerebellum. Activation was markedly reduced in the contralateral somatosensory cortex, parietal cortex (Brodmann area 40, BA40), prefrontal cortex (BA9), putamen and the ipsilateral amygdala during H-DP. Subjects also reported a significant decrease in pain intensity from N-W to H-DP. CONCLUSION: Pain response during H-DP was reduced in sensory and affective pain-related areas, reflecting the diminished intensity of the perceived pain. Moreover, a network of cortical and subcortical areas that have been implicated in the perception of the own body was less responsive during DP, which might point to a specific neural mechanism underlying the 'out-of-body' experience. Although the small number of subjects does not allow a generalization of our findings, H-DP seems to be a promising tool for the investigation of psychological and biological mechanisms of self-inflicted injuries as well as the mind-body interplay within the realm of psychosomatic disorders.

Adult↗

PubMed2000

Interventional radiologic procedures: patient anxiety, perception of pain, understanding of procedure, and satisfaction with medication--a prospective study.

PURPOSE: To prospectively assess patient anxiety, understanding of the procedure being performed, perception of pain level, and satisfaction with medication given for a variety of diagnostic and therapeutic vascular and visceral (nonvascular) interventional procedures. MATERIALS AND METHODS: The authors interviewed 204 patients before and after they underwent an interventional radiologic procedure. Patients responded to a series of questions by using a visual analog scale. Patients were grouped according to (a) their level of experience with the procedure and (b) the type of procedure performed (diagnostic or therapeutic visceral procedure or diagnostic or therapeutic vascular procedure). RESULTS: Patients who had previous experience with a procedure, whether visceral or vascular, were less anxious, had more understanding, and anticipated less pain than did those who did not have experience with a procedure. Patients who had only local anesthesia for visceral biopsy experienced greater pain than did those who had both local and intravenous anesthesia. Satisfaction scores, however, were similar throughout all groups. CONCLUSION: Patients have a moderate amount of anxiety about interventional procedures and anticipate some discomfort. Most patients have a high level of satisfaction despite the amount of pain they experience during the procedure. Patients experienced with a procedure tend to have a greater understanding of the procedure and less anxiety.

Adult↗

PubMed2004

Cardiac syndrome X. Diagnosis, pathogenesis and management.

Patients with cardiac syndrome X (typical chest pain and normal coronary arteriograms) represent a heterogeneous syndrome, which encompasses different pathogenic mechanisms. Although symptoms in most patients with cardiac syndrome X are non-cardiac, a sizable proportion of them have angina pectoris due to transient myocardial ischemia. Thus radionuclide myocardial perfusion defects, coronary sinus oxygen saturation abnormalities and pH changes, myocardial lactate production and stress-induced alterations of cardiac high energy phosphate suggest an ischemic origin of symptoms in at least a proportion of patients with cardiac syndrome X. Microvascular abnormalities, caused by endothelial dysfunction, appear to be responsible for myocardial ischemia in patients with cardiac syndrome X. Endothelial dysfunction is likely to be multifactorial in these patients and it is conceivable that risk factors such as hypertension, hypercholesterolemia, diabetes mellitus and smoking can contribute to its development. Most patients with cardiac syndrome X are postmenopausal women and estrogen deficiency has been therefore proposed as a pathogenic factor in female patients. Additional factors such as abnormal pain perception may contribute to the pathogenesis of chest pain in patients with angina pectoris and normal coronary angiograms. Although prognosis is good regarding survival, patients with cardiac syndrome X have an impaired quality of life. Management of this syndrome represents a major challenge to the treating physician. Understanding the mechanism underlying the condition is of vital importance for patient management. Thus diagnostic tests should aim at identifying the cause of the symptoms in the individual patient, i.e. myocardial ischemia, increased pain perception, abnormalities of adrenergic tone, non-cardiac mechanisms, etc. Moreover, it is important to bear in mind that treatment of cardiac syndrome X should be mainly directed towards improving quality of life, as prognosis is usually good in these patients. Conventional antianginal agents such nitrates, calcium channel antagonists, beta-adrenoceptor antagonists and nicorandil are effective particularly in patients in whom chest pain and ECG changes are clearly suggestive of myocardial ischemia and in those with objective documentation of ischemia. Angiotensin-converting enzyme inhibitors have been shown to be useful in syndrome X patients with increased adrenergic tone, borderline systemic hypertension, and those with documented endothelial dysfunction. Analgesic interventions of different sorts have been proposed based on the hypothesis that somatic and visceral perception of pain is altered in cardiac syndrome X patients. Pharmacological agents such as imipramine and aminophylline, and neural electrical stimulation techniques have been assessed in recent years with encouraging results. Psychological treatment, particularly cognitive therapy, appears to be useful in defined patient subsets. Relaxation techniques such as transcendental meditation have been successfully used in small studies and shown to improve not only chest pain but also exercise-induced ST segment changes. Reports indicate that these techniques improve quality of life.

Disease Management↗

PubMed1995

Effects of arithmetic mental stress test on hypertension-related hypalgesia.

AIM: Though hypertension-related hypalgesia has been described, little is known about possible variation of pain perception after mental stress. The aims of the present study were to determine (1) whether mental stress can influence pain perception in normotensive and hypertensive subjects and (2) whether blood pressure levels before pain evaluation can account for changes in pain sensitivity. PATIENTS AND METHODS: A pulpar test (graded increase in test current of 0-0.03 mA applied on healthy teeth) was performed twice (time interval 15 min) in 62 subjects. Thirty-eight subjects (group 1) performed an arithmetic mental stress test immediately after the first pulpar test while 24 subjects (group 2) did not. The pain threshold (occurrence of pulp sensation) was evaluated as the mean value of three teeth tested on each subject and as the value on the most sensitive tooth. RESULTS: Twenty-eight subjects with normal 24-h blood pressure showed a lower mean pain threshold than 34 subjects with high 24-h blood pressure values (P<0.02). In group 1 (20 normotensives, 18 hypertensives), even when the mental stress increased the pretest blood pressure, the pressure values immediately before both pulpar tests remained similar. In the second pulpar test, a significant increase in the pain threshold on the most sensitive tooth was observed in group 1 (P<0.005). Though a trend towards an increase in the pain threshold was found in both the subgroups of normotensive and hypertensive subjects, the difference was significant in hypertensives only. However, group 2 subjects showed unchanged pain sensitivity on the second test. CONCLUSIONS: A mental stress-induced reduction in pain sensitivity was observed in the absence of change in arterial pressure measured immediately before pulpar tests. A blood pressure increase during the test and, more likely, cortical and humoral activation during stress, may account for the variation found in pain perception.

Adult↗

PubMed1983

Semantic functional measurement of pain: integrating perception and language.

This study used Functional Measurement (FM) scaling procedures to demonstrate that subjects can scale and average the intensity or unpleasantness of pain sensations produced by an electrical tooth pulp stimulus and symbolized by a word. Unlike conventional psychophysical scaling methods, FM includes a testable validity criterion that must be met before the resultant scales are accepted. Twenty subjects used a handgrip dynamometer to rate all possible pairs of (1) 5 tooth pulp stimuli ranging in equal log steps from pain threshold to tolerance, and (2) 5 descriptors of sensory intensity or unpleasantness, twice each for a total of 50 stimulus pairs. The results show that subjects can average the pain magnitude produced by a tooth pulp stimulus with pain magnitude symbolized by a word and that this ability varies with the type of words used. FM produces separate scales of pain intensity, verbal magnitude and psychophysical ability. This method may provide a new and promising tool for the assessment of pain experience.

Adult↗

PubMed1991

Sex differences in the perception of noxious heat stimuli.

This study compared pain perception in young male and female subjects, using experimental noxious heat stimuli. During 2 sessions, each of 40 subjects rated the magnitude of 120 heat stimuli, ranging from 45 degrees C to 50 degrees C. The study included a comparison of visual analogue and magnitude matching rating procedures, as well as a test of simulated analgesia, in which the range of stimuli presented during the 2 experimental sessions was shifted by 1 degree C. We found that females rated noxious heat stimuli as more intense than did males, independent of the gender of the experimenter or the type of rating scale. In addition, the data suggest that females discriminate among the painful heat intensities better than males. For example, female subjects showed significant between-session discrimination of noxious heat stimuli, while male subjects did not, and females produced steeper within-session stimulus-response functions than did males. These observed differences in nociceptive discrimination between males and females indicate that the sex-related variation in pain perception is probably related to sensory factors rather than differences in attitude or emotional response.

Adult↗

PubMedDate not supplied

Nursing staff members' perceptions of pain indicators in persons with severe dementia.

OBJECTIVES: The aims of this study were to (1) identify behaviors that occur in noncommunicative nursing home residents that are perceived by nurses to be indicators of pain, (2) determine factors affecting the differentiation of pain behaviors from similar behaviors due to other causes, and (3) assess nurses' perceptions of the prevalence and importance of specific indicators of pain as well as barriers to the detection of pain in this population. SETTING AND PATIENTS: Seventy-two staff members of three nursing homes were interviewed and surveyed about specific behaviors associated with pain. Focus groups were conducted with staff to validate pain indicators and investigate perceptions of their own ability to identify pain. RESULTS: Nursing staff members agreed on a core group of behaviors that they perceive as pain indicators in elderly persons suffering from dementia. These indicators include specific physical repetitive movements, vocal repetitive behaviors, physical signs of pain, and changes in behavior from the norm for that person. The nursing staff members' level of familiarity with the residents was reported to have a significant effect on staff members' ability to identify and differentiate pain behaviors from other behaviors of impaired residents. Barriers to the detection of pain pertain to staff issues, resident behaviors, and resident-staff relationships. CONCLUSIONS: The study of pain among the noncommunicative elderly and, in particular, the development of a tool that can be used to assess their pain may greatly improve the quality of life of the estimated 20% to 35% of nursing home residents who cannot adequately express their needs.

Aged↗

PubMed1984

Differential effects of phenylbutazone and local anesthetics on nociception in the equine.

The effects of procaine, mepivacaine and phenylbutazone on pain perception in the equine were studied using two behavioral assays of nociception; the thermal evoked hoof withdrawal reflex and skin twitch reflex. Pain perception threshold was measured as the latency from onset of thermal stimuli to reflex withdrawal of the forelimb or contraction of the cutaneous musculature. Procaine 2% and mepivacaine 2% prolonged the hoof withdrawal reflex latency when administered locally by producing a block of the palmar and metacarpal nerves. Significant analgesia lasted 90 min and 210 min for procaine and mepivacaine, respectively. Phenylbutazone (7.3 mg/kg) failed to alter pain thresholds measured over a 36 h post-treatment period. However, pain thresholds rose over time with successive trials. These data suggest that in the equine (1) phenylbutazone does not alter normal cutaneous pain perception, and (2) successive presentation of painful stimuli increases nociceptive thresholds.

Analgesia↗

PubMed1993

Perceptions of pain and pain relief in labour: the gulf between experience and observation.

In a national sample of 10,702 women delivered in one week in 1990 data on their perceptions of pain and the effectiveness of pain relief methods were compared with those of the professionals attending them. Professionals' conceptions of pain relief tended to be restricted to pharmacological methods. Overall, the level of agreement about effectiveness of pain relief was quite low, with medical staff commonly believing they were providing adequate pain relief while the women reported it as unsatisfactory. This was particularly the case for pethidine, while 'Entonox' was rated more highly by women than staff. Professionals were significantly more likely to agree with one another about effectiveness than to agree with the women, and were less likely to have responded where the women judged their pain relief as poor.

Attitude of Health Personnel↗

PubMed1998

Pain comparison after subcutaneous administration of single-dose formulation versus multidose formulation of epogen in hemodialysis patients.

Subcutaneous (s.c.) injection is an approved route of administration for recombinant human erythropoietin (epoetin alfa). However, pain at the injection site with the single-dose formulation has limited its use. With the recent development of a multidose formulation containing benzyl alcohol as a preservative, anecdotal reports have emerged that suggest this product causes less stinging. Using a randomized, triple-blind, placebo-controlled crossover design, this study compared pain perception, intensity, and duration after s.c. injection with a multidose formulation versus single-dose formulation using visual analogue (VAS) and verbal descriptive pain scales (VDS). Twenty-eight hemodialysis patients received s.c. injections of placebo (normal saline) in one arm and either the multidose or single-dose formulation in the opposite arm. One week later, the subjects again received placebo in one arm and the other epoetin alfa formulation in the opposite arm. The VAS and VDS measurements were obtained at time 0 and then every 5 minutes for a period of 30 minutes. Results showed a statistically significant difference in pain perception between formulations at times 0, 10, and 15 minutes for both the VAS and VDS. In conclusion, there was a significant difference in pain perception between formulations with the multidose formulation causing less pain than the single-dose formulation. However, it should be noted that several patients reported no pain with the single-dose formulation. This indicates that individual patient response could be considered when deciding which formulation to use, although it may be difficult to implement an error-free distribution and administration system using the two different formulations.

Adult↗

PubMed1989

Human pain responsivity in a tonic pain model: psychological determinants.

Human pain responsivity was defined as the subject's behavioral pain endurance time (PET) to the 1 +/- 0.3 degrees C cold-pressor test, a naturalistic and clinical analogue tonic pain model. Over the past 2 years, we have consistently observed a behavioral dichotomy of pain responsivity in each of our 6 studies (all at P less than 0.000001 effect level), totaling 205 subjects. Overall, the pain-tolerant (PT) subjects could endure the whole 5 min (note that 3 min was the ceiling criterion in the last study) of cold-pressor test, while the pain-sensitive (PS) subjects could merely tolerate the test for an overall mean of 60 sec, 20% of PET in the PT group. No overlapping of distribution was observed between these 2 populations. Further, we observed that the percentage of subjects in each of these 2 groups varied substantially across studies. The mean pain perception (Visual Analogue Scale) of tonic pain ranged from 60-70 for both aversiveness and intensity scales. The characteristics of this tonic pain, assessed by the McGill Pain Questionnaire (MPQ), showed similar patterns across each study with a high degree of consistency. Although ratings of pain aversiveness did not differ in the PT vs. PS subjects, ratings of pain intensity did differ, with the PT subject reporting less pain. It was found that state anxiety correlated with MPQ scores for PS, but not PT, subjects. Additionally, psychological tests (Tellegen Absorbance Scale, Kleinknecht Fear, Spielberger Trait-Anxiety) were positively correlated with certain MPQ measures for PS, but not PT subjects. Multivariate regression analyses indicated, in the PS but not the PT group, that 36% of variance in pain score (MPQ-T) could be predicted by the psychological trait factors. The general level of fear contributed singularly as the major predictor variable in the pain-sensitive individuals. We consider this tonic pain model indeed offers a succinct empirical paradigm to study human pain responsivity in general. The psychological/physiological etiology of such drastic human pain responsivity requires intense systematic investigations. This report discusses the results in: (a) individual differences in pain responsivity, (b) characterization of the cold-pressor test as a model for tonic pain, (c) contrast between PS and PT groups of pain perception and state anxiety, and (d) psychological determinants of measures for cognitive, perceptual and affective domains. Discussion was also focused on the experimental tonic pain model and its generality for clinical pain, as well as the basic model of the cold-pressor test for human tonic pain responsivity.

Adolescent↗