The effects of belief on acupuncture analgesia.

24 undergraduates who had indicated either a high or low level of belief in acupuncture-induced analgesia received either acupuncture or a pseudo-acupuncture treatment prior to a 60-sec cold-pressor test. Ss also completed the State scale of the State-Trait Anxiety Inventory at the beginning of the experiment and provided ratings of pain intensity during the cold-pressor test. Ss who held positive beliefs about the effectiveness of acupuncture and who received actual acupuncture treatment reported lower pain than did Ss with negative beliefs and those who received pseudo-acupuncture. Anxiety ratings did not differ between groups. The ratings of belief in acupuncture shown by the 2 groups tended to converge after treatment. Results suggest that differences in the analgesic effects of acupuncture are influenced by expectancy effects and the degree to which expectations are confirmed during the treatment procedure. (French abstract) (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive strategies, expectancy, and coping style in the control of pain.

Measures of tolerance, self-reported pain threshold, and overall discomfort of cold-pressor pain were obtained from 114 male undergraduates in a pretest–training–posttest experiment. Training consisted of brief practice in 1 of 4 cognitive strategies: rational thinking, compatible imagery, incompatible imagery, and task-irrelevant cognition. Analyses of covariance indicated that (a) cognitive-imaginal strategies facilitated endurance of pain and raised self-reported threshold, (b) rational thinking and compatible imagery were generally the most effective treatments, (c) expectancy alone was not a significant pain-attenuating factor, (d) treatments did not affect discomfort ratings, and (e) individual differences in imaginal ability and coping style did not correlate with changes in any of the dependent measures. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reduction of cold-pressor pain with acupuncture analgesia in high- and low-hypnotic subjects.

Examined the effect of acupuncture on the cold-pressor pain of high and low hypnotically susceptible undergraduates. The 24 high-susceptible Ss and the 24 low-susceptible Ss verbally reported their course of pain over each 60-sec cold-pressor trial on a numerical rating scale. On Trial 1, in which no groups received treatment, pain ratings did not differ between groups. On Trial 2, Ss who received acupuncture reported significantly less pain than their no-treatment counterparts. The Treatment by Susceptibility interaction was significant, with high-susceptible Ss being more responsive to acupuncture. When an acupuncture effect occurred, it was invariably one of pain reduction; in no case was pain elimination reported. It is concluded that hypnotic susceptibility may be a relevant dimension of individual differences in responsivity to acupuncture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The formation of 1-hydroxymethylnaphthalene and 6-hydroxymethylquinoline by both oxidative and reductive routes in Cunninghamella elegans

The cold-pressor test is a widely used pain-induction model in humans. This method has been shown to be a sensitive measure for detecting opioid analgesia. However, nonsteroidal anti-inflammatory drugs have not produced consistent analgesic effects with use of this model. The analgesic effect of acetaminophen (INN, paracetamol) on cold pressor-induced pain has not been reported by other investigators. In this study, a double-blind, randomized, placebo-controlled design was used to evaluate the dose-related effects of oral acetaminophen on cold pressor-induced pain in 18 normal healthy human subjects. We observed dose-related analgesic activity of oral acetaminophen using the cold pressor-induced pain model in these subjects. There were statistically significant main effects of both dose and time (pain and bothersomeness ratings decreased with increasing drug dose and increased over time). In pairwise comparisons only the contrast between the highest dose of acetaminophen (1000 mg) and placebo reached statistical significance. Results from our study suggest that the cold-pressor method may have clinical value in evaluating nonopioid analgesic agents.     

Attention, distraction, and cold-pressor pain.

Compared the effects of distracting oneself from, vs attending to, the sensations produced by cold-pressor stimulation. Exp I (35 undergraduates) revealed that distraction was a better coping strategy than attention to sensations when Ss were asked to report pain threshold and tolerance. Exps II and III (75 Ss) examined the hypothesis that distraction is effective because persons hold a commonsense belief in the benefits of distraction as a coping device. Neither experiment supported the commonsense hypothesis as an explanation for Exp I's results. In Exp IV, 39 male Ss were assigned to either distraction, attention, or no-instruction conditions and asked to report their distress during a 4-min cold-pressor trial. Distraction reduced distress early in the trial, but attention to sensations was a superior strategy for the last 2 min. It is proposed that distraction and attention to sensations may be differentially effective depending on the duration of the painful stimulus. Possible mediating processes underlying the 2 strategies are discussed. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental designs, expectancy effects, and hypnotic analgesia.

40 undergraduates who scored high on the Harvard Group Scale of Hypnotic Susceptibility were randomly assigned to 1 of 4 groups. Each group received 3 60-sec immersions of cold-pressor pain stimulation. Immersions were associated with either hypnotic, waking, or no analgesia (control) instructions. The treatments and their order were varied across groups to induce different expectations about the efficacy of hypnotic and waking analgesia. Magnitude estimates and category scale ratings of pain indicated that hypnotic analgesia was more, less, or equally as effective as waking analgesia, depending on the expectations induced by varying treatment order. Pain ratings were also related to the type of cognitive activity (e.g., imaginative coping) engaged in during an immersion. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Delayed costs of suppressed pain.

Demonstrates that the rebound effect of thought suppression (D. M. Wegner, 1989) has an analog in the experience of somatic discomfort. During a cold-pressor pain induction, 63 Ss were instructed either to concentrate on their room at home (distraction), to pay close attention to their hand sensations (monitoring), or to remove awareness of those sensations from mind (suppression). Two minutes of postpressor pain ratings showed that monitoring produced the most rapid recovery from the pain and that suppression produced the slowest. Suppression also contaminated the interpretation of a subsequent somatic stimulation; later in the experimental hour, Ss who had suppressed their cold-pressor discomfort rated an innocuous vibration as more unpleasant than did other Ss. The strategies are discussed for their necessarily distinct processes of goal evaluation and their possibly differential drain on perceived coping capacities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory for pain and the delayed effects of distraction.

In spite of the popular belief that distraction is effective in coping with pain, there is evidence that a neutral distractor does not reduce people's reports of pain. However, it may be that distraction's effect is not detectable in immediate ratings, when the need to rate the pain forces the sufferer to concentrate on it. Instead, after a delay, when the pain itself is gone and the person must base the judgment on a memory of the event, having been distracted may attenuate the recalled pain. An experiment with 72 undergraduate participants tested this proposition, with 1 group highly distracted during cold-pressor pain and 1 group slightly distracted. Half of each group rated the pain immediately, and half waited 10 min after the event to rate the pain. The participants who gave immediate ratings showed no effect of distraction, but for participants who waited 10 min before giving their ratings, high distraction led to reduced reports of pain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of assessment methods on self-efficacy and outcome expectancy ratings of assertive behavior.

The study evaluated whether alternate assessment methods contribute to variability in self-efficacy and outcome expectancy ratings for refusal of unreasonable requests. Subject assertiveness plus two methods of scene presentation (i.e., printed vs videotape) and two methods of response generation (i.e., experimenter-prepared vs. subject thought-listed) were compared in a repeated measures design. All subjects were exposed to eight request situations that were matched for legitimacy level and target person. Each situation reflected one of four combinations of assessment methods and served to elicit either an efficacy or outcome expectancy rating. For self-efficacy ratings, there was a significant interaction that indicated that the printed scene plus experimenter-prepared response condition yielded significantly higher ratings than all of the other conditions. For outcome expectancy ratings, there was a main effect for response-generation method indicating that the thought-listing method led to lower expectancy of positive outcomes. Also, consistent with past research, assertive subjects reported more positive than negative outcome expectancies. These plus other findings are discussed relative to the cognitive assessment and self-efficacy literatures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effectiveness of maximally different cognitive strategies and expectancy in attenuation of reported pain.

Ninety-six Ss rated pain during baseline and posttreatment exposures to cold pressor pain. Between trials, Ss in four groups were trained to use one of four cognitive coping strategies involving (a) imaginal reinterpretation, (b) imaginal distraction, (c) nonimaginal reinterpretation, or (d) nonimaginal distraction. Two additional groups were given: (e) an expectation for analgesia but no coping strategy and (f) no treatment. The four coping strategies produced equivalent attenuation of pain ratings and equivalent expectancies for analgesia. Expectancy control Ss expected analgesia, but reported no significant pain reductions. No treatment control Ss neither expected nor achieved any significant pain reductions. Among cognitive strategy groups, the Ss' absorption added significantly to the variance in pain reduction above and beyond the effects of expectancy. Theoretical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Alterations in echinocyte transformation and erythrocyte sedimentation rate during hemodialysis

In spite of the popular belief that distraction is effective in coping with pain, there is evidence that a neutral distractor does not reduce people's reports of pain. However, it may be that distraction's effect is not detectable in immediate ratings, when the need to rate the pain forces the sufferer to concentrate on it. Instead, after a delay, when the pain itself is gone and the person must base the judgment on a memory of the event, having been distracted may attenuate the recalled pain. An experiment with 72 undergraduate participants tested this proposition, with 1 group highly distracted during cold-pressor pain and 1 group slightly distracted. Half of each group rated the pain immediately, and half waited 10 min after the event to rate the pain. The participants who gave immediate ratings showed no effect of distraction, but for participants who waited 10 min before giving their ratings, high distraction led to reduced reports of pain.     

Gender differences in willingness to pay to avoid pain and their correlation with risk.

This article presents experimental evidence on forced choices between inferior alternatives. In asking subjects to make trade offs between an experimentally induced cold-pressor pain of different durations and paying money to avoid the administration of pain, we try to shed some light on the questions: (a) are there any gender differences in elicited willingness to pay (WTP) values for pain; (b) when present, is differing WTP across genders better explained by measures of risk-aversion or measures of loss-aversion; and (c) we further investigate whether there are variations in hypothetically elicited WTP values (hypothetical pain and hypothetical money) and WTP values elicited when subjects face real consequences (both real pain and real money). Our results confirmed the hypothesis of significant gender differences in elicited WTP values in both the hypothetical and real groups. We also found some evidence of significant differences due to the treatment. Subjects who experienced the cold-pressor pain only once (hypothetical group) exhibited on average greater WTP compared with subjects who experienced the cold-pressor pain multiple times (real group). Females, however, stated lower WTP in the real treatment while for males the effect was in the opposite direction. Moreover, we found risk attitudes to be significantly associated with WTP while loss-aversion not. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Rating pain or rating serenity: Effects on cold-pressor pain tolerance.

Investigated the effects of 2 self-report procedures on tolerance for pain. 58 female undergraduates, prescreened using a scale of absorption, or heightened attention, received 2 trials of a cold-pressor task. Ss gave ratings of either pain or calmness or no rating. Both self-report procedures resulted in significantly greater tolerance times than the no-rating condition. Tolerance was similar in each self-report condition. It is concluded that self-reports foster the use of coping strategies and thus divert attention away from noxious sensations. No differences in tolerance were found for high and low absorption scores, suggesting that absorption does not mediate the effects of self-report procedures. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A blinded, randomized, paired, placebo-controlled trial of 20-minute EMLA cream to reduce the pain of peripheral i.v. cannulation in the ED

A eutectic mixture of local anesthetics (EMLA) in cream form has been used as a topical anesthetic to reduce the pain of procedures penetrating the skin. It is generally applied for 45 to 60 minutes before the painful procedure. The purpose of this study was to determine whether a 20-minute application of EMLA is useful in reducing the pain of routine peripheral intravenous cannulation in the emergency department (ED). A blinded, randomized, placebo-controlled, paired trial compared the pain of intravenous cannulation in both hands of study subjects: one hand was treated with 20-minute EMLA cream and the other hand was treated with 20-minute placebo cream. Forty subjects identified the more painful hand and scored pain measurements of each hand using a 10-cm visual analog scale. These data failed to demonstrate any significant benefit of EMLA compared with placebo. EMLA is not useful for intravenous cannulation when used for 20-minute application times. There may be more effective and less costly ways of reducing the pain of intravenous cannulation that patients would prefer.     

Attributional mediators of evaluation, expectancy, and affect: A response time analysis.

In two studies we examined the informational value of ability and effort cues as guides to achievement-related judgments about others. Using a response time methodology, we first presented subjects with information concerning how much ability a failing student had, how hard the student tried, or both. Subsequently, subjects reported interpersonal evaluations, expectancy predictions, and affective judgments of guilt, shame, and unhappiness. Interpersonal evaluations were made the most rapidly when effort information was provided, and expectancy predictions were made the most rapidly when ability information was provided. These data were consistent with an attributional analysis of effort as a more informative causal cue for evaluation and ability as a more informative cue for expectancy. There was only modest support for related hypotheses concerning the cue value of effort and ability as guides to affective judgments. Finally, the response time data provided evidence for an attributional conception of increasingly complex causally mediated judgments. We discuss implications for causal inference and for self-perception. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Analgesia for experimentally induced pain: Multiple sessions of acupuncture compared to hypnosis in high- and low-susceptible subjects.

Repeated trials with cold-pressor pain were used to (a) determine whether the modest relation between hypnotic susceptibility and response to acupuncture analgesia obtained in previous experiments is enhanced over a series of treatments; (b) compare acupuncture and hypnotic analgesias; and (c) assess whether acupuncture analgesia increases with repeated treatments. 20 high and 20 low hypnotically susceptible undergraduates participated on 5 days. For half of each susceptibility group, Sessions 1–3 consisted of a baseline trial followed by an acupuncture analgesia trial. The remaining Ss had 2 no-treatment trials on each of these sessions. For all Ss Session 4 was a baseline followed by a hypnotic analgesia trial, and Session 5 was a repetition of the procedures followed in Sessions 1–3. Repeated exposures to acupuncture did not alter its analgesic effect in either susceptibility group; there were no instances of significant postacupuncture pain reduction. High, but not low, susceptibles reported marked pain reduction after hypnotic analgesia. The effect of acupuncture on experimentally induced pain is at best small and fragile. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Instructional demands and ratings of overt and hidden pain during hypnotic analgesia.

16 highly hypnotizable (Carlton University Responsiveness to Suggestion Scale) undergraduates rated the intensity of cold pressor pain during a baseline trial and again during 3 hypnotic analgesia trials. During each analgesia trial, Ss were instructed to give overt reports that reflected consciously experienced pain and covert reports that reflected the intensity of "hidden" pain. Treatment instructions administered before the 1st analgesia trial did not specify the relationship between overt and covert pain. Instructions given before the remaining 2 analgesia trials indicated that hidden pain would be either more or less intense than overt pain. Until they were given explicit information about the relative intensities of the pain, Ss reported no differences in the magnitude of overt and covert pain, contrary to the dissociation hypothesis of hypnotic analgesia. Consistent with social psychological formulations of the hidden observer phenomenon, Ss reported both higher covert than overt pain and lower covert than overt pain, depending on the instructions they were administered. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Examiner expectancy effects in the measurement of pressure pain thresholds

The ascending Method of Limits, used for the determination of pressure pain thresholds (PPT), is not a psychophysically robust method. The present study sought to determine if the examiner's expectancy, based on whether the measurement site was clinically 'painful' or 'non-painful', would bias the obtained PPT values. Twenty-eight patients with facial or temporal area pain served as subjects, and in each subject, a pain site and a control site were identified and marked. According to a randomization schedule, the pain and control sites were correctly marked in half of the subjects and were mis-labeled in the other half, thereby controlling the examiner's knowledge of a site and thus the examiner's expectancy of what the PPT should be. Two examiners, shown to be reliable with each other in both pre-clinical and post-clinical reliability studies, were blind to the true purpose of the study and to the marking procedures. Each examiner made one PPT measurement at each marked site in a counterbalanced measurement order. Manipulating the examiner's prior knowledge of the measurement site's characteristics significantly lowered the obtained PPT values for control sites but did not significantly alter the PPT at the clinically painful sites. Nevertheless, the pain sites still had significantly lower PPTs than did control sites. We conclude that: (i) PPTs at pain sites are robust to a major source of measurement bias associated with the ascending Method of Limits; (ii) measurement order and knowledge of measurement site characteristics can influence obtained PPT; and (iii) the common protocol in which the examiner monitors the amount of pressure during PPT measurement in order to control the force application rate may serve as a mechanism that can bias the obtained values.     

Judging nonverbal expressions of pain.

Examined the impact of pain-relevant, biasing information on judgments of the pain expressed in facial displays. 15 male and 15 female Ss (mean age 19.5 yrs) judged the videotaped expressions of females experiencing low, medium, and high intensity electric shocks. Ss were informed either that the shocked females had been exposed to a hypersensitivity or analgesic treatment, or the Ss received no prior information. The shocked females also had been exposed previously to either a tolerant social modeling or a no influence control condition, so that the impact of a social influence strategy on nonverbal expressions of pain could be examined. Sensory decision theory analyses of Ss' ratings indicated that the hypersensitivity instruction led to reports of greater observed pain in the absence of an effect on the ability to discriminate pain displays. Exposure of the shocked females to the tolerant modeling influence strategy dampened the pain display, making discriminations among the differing severities of electric shock more difficult. Results indicate that providing judges with information extrinsic to another person's distress can alter the severity of pain attributed to the other person. The discriminability analyses supported the conclusion that modeling influences are fundamental determinants of a broad range of reactions to pain, including nonverbal behavior. (French abstract) (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Negative and positive pretrial publicity affect juror memory and decision making.

The experiment examined the effects of exposure to pretrial publicity (PTP) and delay on juror memory and decision-making. Mock jurors read news articles containing negative PTP, positive PTP, or unrelated articles. Five days later, they viewed a videotaped murder trial, after which they made decisions about guilt. Finally, all participants independently attributed specific information as having been presented during the trial or in the news articles. Half of the jurors rendered their verdicts and completed the source-memory test immediately after the trial, while the other half did so after a 2-day delay. Exposure to PTP significantly affected guilty verdicts, perceptions of defendant credibility, juror ratings of the prosecuting and defense attorneys, and misattributions of PTP as having been presented as trial evidence. Similar effects were obtained for negative and positive PTP. Delay significantly increased source-memory errors but did not influence guilt ratings. Defendant's credibility and juror ratings of prosecuting and defense attorneys significantly mediated the effect of PTP on guilt ratings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)