Structural and functional cerebral correlates of hypnotic suggestibility.

Little is known about the neural bases of hypnotic suggestibility, a cognitive trait referring to the tendency to respond to hypnotic suggestions. In the present magnetic resonance imaging study, we performed regression analyses to assess hypnotic suggestibility-related differences in local gray matter volume, using voxel-based morphometry, and in waking resting state functional connectivity of 10 resting state networks, in 37 healthy women. Hypnotic suggestibility was positively correlated with gray matter volume in portions of the left superior and medial frontal gyri, roughly overlapping with the supplementary and pre-supplementary motor area, and negatively correlated with gray matter volume in the left superior temporal gyrus and insula.

Ranking brain areas encoding the perceived level of pain from fMRI data.

Pain perception is thought to emerge from the integrated activity of a distributed brain system, but the relative contribution of the different network nodes is still incompletely understood. In the present functional magnetic resonance imaging (fMRI) study, we aimed to identify the more relevant brain regions to explain the time profile of the perceived pain intensity in healthy volunteers, during noxious chemical stimulation (ascorbic acid injection) of the left hand. To this end, we performed multi-way partial least squares regression of fMRI data from twenty-two a-priori defined brain regions of interest (ROI) in each hemisphere, to build a model that could efficiently reproduce the psychophysical pain profiles in the same individuals; moreover, we applied a novel three-way extension of the variable importance in projection (VIP) method to summarize each ROI contribution to the model.

Hypnotic susceptibility modulates brain activity related to experimental placebo analgesia.

Identifying personality traits and neural signatures that predict placebo responsiveness is important, both on theoretical and practical grounds. In the present functional magnetic resonance imaging (fMRI) study, we performed multiple-regression interaction analysis to investigate whether hypnotic susceptibility (HS), a cognitive trait referring to the responsiveness to suggestions, explains interindividual differences in the neural mechanisms related to conditioned placebo analgesia in healthy volunteers. HS was not related to the overall strength of placebo analgesia.

Postural effects of imagined leg pain as a function of hypnotizability.

It has been shown that, in subjects with high hypnotizability (Highs), imagined somatosensory stimulation can involuntarily activate the neural circuits involved in the modulation of reflex action. In this vein, aim of the study was to investigate whether the imagery of nociceptive stimulation in one leg may produce both subjective experience of pain and congruent postural adjustments during normal upright stance. The displacement of the centre of pressure (CoP) was studied during imagery of leg pain (LP) and during the control conditions of imagery of tactile stimulation of the same leg and of throat pain (TP) in 12 Highs and 12 low hypnotizable subjects (Lows).

Hypnotizability and sensorimotor integration: an Italian Space Agency project.

In highly hypnotizable individuals (highs), postural control is more independent of sensory information than in low hypnotizable subjects (lows). The aim of the study was to find out whether locomotion is also less affected in highs than in lows by visual suppression and changes in the neck proprioceptive input. Eighteen highs and 20 lows were asked to walk straight ahead, blindfolded, in basal conditions (face forward), during real and imagined right/left head rotation and mental computation.

Alexithymia in fibromyalgia syndrome: associations with ongoing pain, experimental pain sensitivity and illness behavior.

Objective: Alexithymia, a lack of emotional awareness, is common in chronic pain patients. The aim of the study was to investigate the relationship of alexithymia to ongoing pain, experimental pain sensitivity, and illness behavior in patients with chronic musculoskeletal pain.

Methods: Sixty-eight women with fibromyalgia (age: average, 43.

Predictors of psychological distress and well-being in women with chronic musculoskeletal pain: two sides of the same coin?

Objective: To date, few results on well-being in chronic-pain patients have been published, while several studies in patients without pain have indicated that well-being may not be equivalent to absence of psychological distress. The aim of the present study was to investigate the relationship between psychological distress and well-being and to identify the predictors of each in patients with chronic nonmalignant pain.

Methods: Sixty-nine women with chronic multiregional musculoskeletal pain, 41 of whom met American College of Rheumatology criteria for fibromyalgia, completed questionnaires on pain, fatigue, stiffness, physical disability (Fibromyalgia Impact Questionnaire), psychological distress [Multidimensional Affect and Pain Survey (MAPS), Symptom Check List-90 (SCL-90), State-Trait Anxiety Inventory Form Y2 (STAI-Y2)], and hedonic and eudaimonic well-being (MAPS).

Dimensions of "unidimensional" ratings of pain and emotions in patients with chronic musculoskeletal pain.

The use of unidimensional scales to measure pain intensity has been criticised because of the multidimensional nature of pain. We conducted multiple linear regression analyses to determine which dimensions of pain--sensory versus affective--predicted scores on unidimensional scales measuring pain intensity and emotions in 109 Italian women suffering from chronic, non-malignant musculoskeletal pain. We then compared the results with earlier findings in two groups of cancer patients suffering from acute post-operative pain and chronic cancer-related pain, respectively.