Variation In Pain Perception Research Articles

Diurnal Variation of Pain Perception in Young Volunteers Using the Tourniquet Pain Model

Pollmann and Hildebrand (1979) have shown that the threshold for tooth pain provoked by cold stimuli in healthy volunteers shows 24 h variation with a maximum at 18:00 h and elevated values through...

Absence of an impact of emotional distress on the perception of intracardiac shock discharges.

The pain of transvenous cardioversion shocks in awake patients is an important clinical problem. It is unknown whether psychological factors modulate any observed variation in pain perception. Thirty-seven patients with chronic atrial fibrillation (AF; mean age 61.9 years, 29 men, 8 women) were consecutively included in the study. Pain perception of a low energy test shock (60V, 0.1J) during internal cardioversion was assessed immediately following the stimulus. Before treatment anxiety, depression, somatization were evaluated. The intracardiac shock was perceived as hypalgesic in 15 (41%) patients, as normalgesic in 10 (27%), and as hyperalgesic in 10 (32%) patients. Pain threshold was significantly lower in patients in which AF was accidentally diagnosed (p < 0.029). Age, sex, and the level of education were equally distributed over the three pain groups. The hyperalgesic pain threshold was not associated with anxiety, depression, or the patients' tendency to amplify benign bodily sensations. This study discloses a wide range of perceived pain intensity caused by a homogenous intracardiac stimulation. Anxiety and depression do not amplify perception of intracardiac shocks. Sensory gating mechanisms may play a more important role in the level of intracardiac shock perception than distressing affective factors.

Functional magnetic resonance imaging of pain consciousness: Cortical networks of pain critically depend on what is implied by “pain”

Brain imaging studies, using primarily functional magnetic resonance imaging (fMRI), are reviewed. These studies are aimed at developing imaging approaches that can be used in the clinical setting to investigate clinically relevant pain states. To this end, our recent studies indicate that by taking advantage of the temporal variations in pain perception, we are able to identify cortical regions that may be uniquely involved in pain consciousness. This procedure in turn becomes a general approach with which clinical pain states can be studied. Preliminary results are shown in patients suffering from chronic reflex sympathetic dystrophy (RSD) and chronic back pain. The review emphasizes that different experimental pain states, and chronic and acute clinical pain states, seem to involve dramatically different networks, the details of which remain to be worked out. It is concluded that these procedures need to be applied in the larger clinical setting in which multicentered studies may be conducted to begin building the brain pain network atlas.

Effects of arithmetic mental stress test on hypertension-related hypalgesia

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. 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. 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. 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.

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°C to 50°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°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.

Diurnal variations in pain perception and thermal sensitivity

Pain and thermal sensitivity thresholds in healthy volunteers were examined for diurnal variations. The subjects were 11 men aged between 22 and 27 years ( x ̄ = 23.5 , S. D. = 1.5). Data were collected for 2 days, with 7 measurements per day. To ensure the pain specificity of the results the subliminal modality i.e., thermal sensitivity thresholds to warm and cold stimuli, was investigated in addition to the threshold for perception of heat pain. Assessments were made on the right hand and foot, the stimuli being presented with a thermoelectric contact-thermode. Despite the influence of variables other than time of day (45–56% of the total variance), diurnal variations were found for some subjects on the pain threshold measure (significant correlation between days and relatively high frequency of 24 h component in Fourier analysis spectra). However, they could not be demonstrated for the thermal sensitivity measures. The diurnal variations in pain perception thresholds did not have a consistent pattern over all subjects (Friedman test). The small diurnal variations with interindividual differences in the pattern are therefore not sufficient to explain the variations seen in clinical pain, but they may be useful in detecting pain modulators by investigating correlations.

Acute and chronic pain in hemophilia

The present study compared acute vs. chronic pain in hemophiliac subjects who suffer both types of pain. Characteristics of the acute pain produced by a hemorrhage into a joint and the chronic arthritic pain that results from repeated bleeding episodes were assessed with the McGill Pain Questionnaire and a visual analogue pain intensity scale. The results showed a high degree of similarity in the sensory, affective and evaluative properties of the two types of pain. The main difference between the acute and chronic pains was one of overall intensity, with the acute pain generally being described as more intense. A comparison of the arthritic pain in hemophilia with the pain of other arthritic disorders revealed no major differences. Sources of inter-individual variability were also explored and the results showed that the pain scores in hemophiliac subjects were largely unrelated to demographic and pain history variables. However, significant differences were observed in the way French- and English-speaking subjects described and rated their pain. Irrespective of the origin of their pain, French-speaking subjects characteristically rated their pain as more intense and more affectively laden than the English group. These results demonstrate that ethnocultural factors associated with language affiliation may contribute to inter-individual variation in pain perception.

The Diurnal Variation in Perception of Pain

Pain Relief Unit, Abingdon Hospital, Abingdon, Oxfordshire, Nuffield Department of Anaesthetics, Radcliffe Infirmary, Oxford, and MRC Perceptual and Cognitive Performance Unit, University of Sussex, Brighton, Sussex, Great Britain

The diurnal variation in perception of pain : C.J. Glynn, J.W. Lloyd and S. Folkard, Proc. roy. Soc. Med., 69 (1976) 369–372

The diurnal variation in perception of pain : C.J. Glynn, J.W. Lloyd and S. Folkard, Proc. roy. Soc. Med., 69 (1976) 369–372

The diurnal variation in perception of pain

The diurnal variation in perception of pain

The diurnal variation in perception of pain

The diurnal variation in perception of pain

The Diurnal Variation in Perception of Pain

The Diurnal Variation in Perception of Pain