33 research outputs found
The role of cognitive reappraisal in placebo analgesia: an fMRI study
Placebo analgesia (PA) depends crucially on the prefrontal cortex (PFC), which is assumed to be responsible for initiating the analgesic response. Surprisingly little research has focused on the psychological mechanisms mediated by the PFC and underlying PA. One increasingly accepted theory is that cognitive reappraisal—the reinterpretation of the meaning of adverse events—plays an important role, but no study has yet addressed the possible functional relationship with PA. We
studied the influence of individual differences in reappraisal ability on PA and its prefrontal mediation. Participants completed a cognitive reappraisal ability task, which compared negative affect evoked by pictures in a reappraise versus a control condition. In a subsequent fMRI session, PA was induced using thermal noxious stimuli and an inert skin cream. We found a region in the left dorsolateral PFC, which showed a positive correlation between placebo-induced activation and (i) the reduction in participants’ pain intensity ratings; and (ii) cognitive reappraisal ability scores. Moreover, this region
showed increased placebo-induced functional connectivity with the periaqueductal grey, indicating its involvement in descending nociceptive control. These initial findings thus suggest that cognitive reappraisal mechanisms mediated by the dorsolateral PFC may play a role in initiating pain inhibition in P
Stress-induced analgesia in patients with chronic musculoskeletal pain and healthy controls
Introduction: Individuals with chronic musculoskeletal pain show impairments
in their pain-modulatory capacity. Stress-induced analgesia (SIA) is a paradigm
of endogenous pain inhibition mainly tested in animals. It has not been tested
in patients with chronic pain despite the important role of stress in pain
modulation and the chronicity process. Methods: SIA was tested in 22 patients
with chronic musculoskeletal pain and 18 healthy participants matched for age
and gender. Pain thresholds, pain tolerance and suprathreshold pain sensitivity
were examined before and after a cognitive stressor. Additionally, chronic
stress levels, pain catastrophizing and pain characteristics were assessed as
potential modulating factors. Results: Patients with chronic musculoskeletal
pain compared to healthy controls showed significantly impaired SIA
(F(1,37)=5.63, p=.02) for pain thresholds, but not pain tolerance
(F(1,37)=0.05, p=.83) and stress-induced hyperalgesia (SIH) to suprathreshold
pain ratings (F(1,37)=7.76, p=.008). Patients (r(22)=-0.50, p=.05) but not
controls (r(18)=-0.39, p=.13) with high catastrophizing had low SIA as assessed
by pain thresholds. In controls suprathreshold pain ratings were significantly
positively correlated with catastrophizing (r(18)=0.57, p=.03) and life-time
stress exposure (r(18)=0.54, p=.03). In patients neither catastrophizing
(r(22)=0.21, p=.34) nor stress exposure (r(22)=0.34, p=.34) were associated
with suprathreshold SIH. Discussion: Our data suggest impairments of SIA and
SIH in patients with chronic musculoskeletal pain. Catastrophizing was
associated with deficient SIA in the patients and higher pain ratings in
controls. High life time stress also increased pain ratings in the controls
An augmented reality home-training system based on the mirror training and imagery approach
Trojan J, Diers M, Fuchs X, et al. An augmented reality home-training system based on the mirror training and imagery approach. Behavior Research Methods. 2013;46(3):634-640
The Importance of Synchrony and Temporal Order of Visual and Tactile Input for Illusory Limb Ownership Experiences : An fMRI Study Applying Virtual Reality
Impact of controllability on pain and suffering
Abstract. Introduction:. Chronic pain and pain-related suffering are major health problems. The lack of controllability of experienced pain seems to greatly contribute to the extent of suffering. This study examined how controllability affects the perception of pain and pain-related suffering, and the modulation of this effect by beliefs and emotions such as locus of control of reinforcement, pain catastrophizing, and fear of pain.
Methods:. Twenty-six healthy subjects received painful electric stimulation in both controllable and uncontrollable conditions. Visual analogue scales and the “Pictorial Representation of Illness and Self Measure” were used to assess pain intensity, unpleasantness, pain-related suffering, and the level of perceived control. We also investigated nonverbal indicators of pain and suffering such as heart rate, skin conductance, and corrugator electromyogram.
Results:. Controllability selectively reduced the experience of pain-related suffering, but did not affect pain intensity or pain unpleasantness. This effect was modulated by chance locus of control but was unrelated to fear of pain or catastrophizing. Physiological responses were not affected by controllability. In a second sample of 25 participants, we varied the instruction. The effect of controllability on pain-related suffering was only present when instructions focused on the person being able to stop the pain.
Discussion:. Our data suggest that the additional measure of pain-related suffering may be important in the assessment of pain and may be more susceptible to the effects of perceived control than pain intensity and unpleasantness. We also show that this effect depends on personal involvement
Assessing suffering in experimental pain models: psychological and psychophysiological correlates
Although suffering is a central issue in pain, there is only little research on this topic. The aim of this study was to assess suffering in an experimental context using various stimulation methods and durations, and to examine which psychological or psychophysiological measures covary with pain-related suffering. Twenty-one healthy volunteers participated in two experiments in which we used tonic thermal and phasic electric stimuli with short and long stimulus durations. The participants rated pain intensity, unpleasantness, and pain-related suffering on separate visual analog scales (VAS) and completed the Pictorial Representation of Illness and Self Measure (PRISM), originally developed to assess suffering in chronic illness. We measured heart rate, skin conductance responses (SCRs), and the electromyogram (EMG) of the musculus corrugator supercilii. For both heat and electric pain, we obtained high ratings on the suffering scale confirming that suffering can be evoked in experimental pain conditions. Whereas pain intensity and unpleasantness were highly correlated, both scales were less highly related to suffering, indicating that suffering is distinct from pain intensity and unpleasantness. Higher suffering ratings were associated with more pronounced fear of pain and increased private self-consciousness. Pain-related suffering was also related to high resting heart rate,
increased SCR, and decreased EMG during painful stimulation. These results offer an approach to the assessment of suffering in an experimental setting using thermal and electric pain stimulation and shed light on its psychological and psychophysiological correlates