Publications by authors named "Axel D Vittersø"

10 Publications

  • Page 1 of 1

Characterising sensorimotor adaptation in Complex Regional Pain Syndrome.

Cortex 2021 Jul 22;140:157-178. Epub 2021 Apr 22.

Centre for Pain Research, University of Bath, Bath, Somerset, United Kingdom; Department of Psychology, University of Bath, Bath, Somerset, United Kingdom.

It has been suggested that sensorimotor conflict contributes to the maintenance of some pathological pain conditions, implying that there are problems with the adaptation processes that normally resolve such conflict. We tested whether sensorimotor adaptation is impaired in people with Complex Regional Pain Syndrome (CRPS) by characterising their adaption to lateral prismatic shifts in vision. People with unilateral upper-limb CRPS Type I (n = 17), and pain-free individuals (n = 18; matched for age, sex, and handedness) completed prism adaptation with their affected/non-dominant and non-affected/dominant arms. We examined 1) the rate at which participants compensated for the optical shift during prism exposure (i.e., strategic recalibration), 2) endpoint errors made directly after prism adaptation (sensorimotor realignment) and the retention of these errors, and 3) kinematic markers associated with strategic control. Direct comparisons between people with CRPS and controls revealed no evidence of any differences in strategic recalibration, including no evidence for differences in a kinematic marker associated with trial-by-trial changes in movement plans during prism exposure. All participants made significant endpoint errors after prism adaptation exposure, indicative of sensorimotor realignment. Overall, the magnitude of this realignment did not differ between people with CRPS and pain-free controls. However, when endpoint errors were considered separately for each hand, people with CRPS made greater errors (indicating more rather than less realignment) when using their affected hand than their non-affected hand. No such difference was seen in controls. Taken together, these findings provide no evidence of impaired strategic control or sensorimotor realignment in people with CRPS. In contrast, they provide some indication that there could be a greater propensity for sensorimotor realignment in the CRPS-affected arm, consistent with more flexible representations of the body and peripersonal space. Our study challenges an implicit assumption of the theory that sensorimotor conflict might underlie some pathological pain conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cortex.2021.03.028DOI Listing
July 2021

Validation of the Bath CRPS Body Perception Disturbance Scale.

J Pain 2021 May 6. Epub 2021 May 6.

Department of Psychology, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom; Centre for Pain Research, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.

The Bath Complex Regional Pain Syndrome Body Perception Disturbance Scale ("B-CRPS-BPDS") measures alterations in body perception. We assessed its internal consistency, known group validity, construct validity, and associations with demographic and clinical characteristics. We also evaluated changes in, and baseline predictors of B-CRPS-BPDS scores at follow-up. We included people with CRPS (N = 114) and pain-free controls (N = 69). People with CRPS obtained higher scores than pain-free controls on all B-CRPS-BPDS items, except the item on attention. Because this item also had an insufficient corrected item-total correlation, we propose a revised B-CRPS-BPDS (r-B-CRPS-BPDS) excluding this item. The internal consistency of the r-B-CRPS-BPDS was good. The r-B-CRPS-BPDS showed a large positive relationship with "motor neglect-like symptoms", indicating good construct validity. The r-B-CRPS-BPDS showed positive relationships with pain intensity, fear of movement, depression, and upper limb disability. There were no independent relationships with handedness, affected side, affected limb, disease duration, CRPS severity score, tension, anger, fatigue, confusion, and vigour. Finally, r-B-CRPS-BPDS scores did not consistently change over time. Our results demonstrate the utility of the r-B-CRPS-BPDS for measuring body perception disturbances in CRPS. PERSPECTIVE: This article evaluates the validity of the Bath Complex Regional Pain Syndrome Body Perception Disturbance Scale ("B-CRPS-BPDS") in CRPS, and assesses relationships with demographic and clinical variables. The proposed revised B-CRPS-BPDS appears to be a valid measure of body perception disturbances in CRPS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jpain.2021.04.007DOI Listing
May 2021

Ignoring space around a painful limb? No evidence for a body-related visuospatial attention bias in complex regional pain syndrome.

Cortex 2021 Mar 24;136:89-108. Epub 2020 Dec 24.

Department of Psychology, University of Bath, Bath, United Kingdom; Centre for Pain Research, University of Bath, Bath, United Kingdom.

Background: Complex Regional Pain Syndrome (CRPS) is a disorder of severe chronic pain in one or more limb(s). People with CRPS report unusual perceptions of the painful limb suggesting altered body representations, as well as difficulty attending to their affected limb (i.e., a 'neglect-like' attention bias). Altered body representations and attention in CRPS might be related, however, existing evidence is unclear. We hypothesized that if there were a body-related visuospatial attention bias in CRPS, then any attention bias away from the affected side should be larger for or limited to circumstances when the (impaired) body representation is involved in the task versus when this is not the case.

Methods: We included 40 people with CRPS, 40 with other limb pain conditions, and 40 pain-free controls. In half of the people with pain, their upper limb was affected, in the other half their lower limb. We administered computerized tasks of spatial attention, including free viewing of images, shape cancellation, temporal order judgement, and dot-probe. The degree to which different versions of each task involved body representation was manipulated by one or more of the following: (1) presenting stimuli nearer versus further away from the body, (2) using body related versus neutral stimuli, and (3) inducing mental rotation of body parts versus no mental rotation. In addition to perceptual judgements, eye movements were recorded as a sensitive index of spatial attention. Bayesian repeated measures analyses were performed.

Results: We found no evidence for a (body-related) visuospatial attention bias in upper limb CRPS. Secondary analyses suggested the presence of a body-related visuospatial attention bias away from the affected side in some participants with lower limb CRPS.

Discussion: Our results add to growing evidence that there might be no general visuospatial attention bias away from the affected side in CRPS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cortex.2020.12.007DOI Listing
March 2021

Prism adaptation treatment for upper-limb complex regional pain syndrome: a double-blind randomized controlled trial.

Pain 2021 02;162(2):471-489

Centre for Pain Research, University of Bath, Bath, United Kingdom.

Abstract: Initial evidence suggested that people with complex regional pain syndrome (CRPS) have reduced attention to the affected side of their body and the surrounding space, which might be related to pain and other clinical symptoms. Three previous unblinded, uncontrolled studies showed pain relief after treatment with prism adaptation, an intervention that has been used to counter lateralised attention bias in brain-lesioned patients. To provide a robust test of its effectiveness for CRPS, we conducted a double-blind randomized controlled trial of prism adaptation for unilateral upper-limb CRPS-I. Forty-nine eligible adults with CRPS were randomized to undergo 2 weeks of twice-daily home-based prism adaptation treatment (n = 23) or sham treatment (n = 26). Outcomes were assessed in person 4 weeks before and immediately before treatment, and immediately after and 4 weeks after treatment. Long-term postal follow-ups were conducted 3 and 6 months after treatment. We examined the effects of prism adaptation vs sham treatment on current pain intensity and the CRPS symptom severity score (primary outcomes), as well as sensory, motor, and autonomic functions, self-reported psychological functioning, and experimentally tested neuropsychological functions (secondary outcomes). We found no evidence that primary or secondary outcomes differed between the prism adaptation and sham treatment groups when tested at either time point after treatment. Overall, CRPS severity significantly decreased over time for both groups, but we found no benefits of prism adaptation beyond sham treatment. Our findings do not support the efficacy of prism adaptation treatment for relieving upper-limb CRPS-I. This trial was prospectively registered (ISRCTN46828292).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/j.pain.0000000000002053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7808368PMC
February 2021

Neuropsychological Changes in Complex Regional Pain Syndrome (CRPS).

Behav Neurol 2020 14;2020:4561831. Epub 2020 Jan 14.

Centre for Pain Research, University of Bath, Claverton Down Road, Bath BA2 7AY, UK.

Complex Regional Pain Syndrome (CRPS) is a poorly understood chronic pain condition of multifactorial origin. CRPS involves sensory, motor, and autonomic symptoms primarily affecting one extremity. Patients can also present with neuropsychological changes such as reduced attention to the CRPS-affected extremity, reminiscent of hemispatial neglect, yet in the absence of any brain lesions. However, this "neglect-like" framework is not sufficient to characterise the range of higher cognitive functions that can be altered in CRPS. This comprehensive literature review synthesises evidence of neuropsychological changes in CRPS in the context of potential central mechanisms of the disorder. The affected neuropsychological functions constitute three distinct but not independent groups: distorted body representation, deficits in lateralised spatial cognition, and impairment of non-spatially-lateralised higher cognitive functions. We suggest that many of these symptoms appear to be consistent with a broader disruption to parietal function beyond merely what could be considered "neglect-like." Moreover, the extent of neuropsychological symptoms might be related to the clinical signs of CRPS, and rehabilitation methods that target the neuropsychological changes can improve clinical outcomes in CRPS and other chronic pain conditions. Based on the limitations and gaps in the reviewed literature, we provide several suggestions to improve further research on neuropsychological changes in chronic pain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2020/4561831DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7201816PMC
January 2021

Disputing space-based biases in unilateral complex regional pain syndrome.

Cortex 2020 06 13;127:248-268. Epub 2020 Mar 13.

Centre for Pain Research, University of Bath, Bath, UK; Department of Psychology, University of Bath, Bath, UK.

There is some evidence that people with Complex Regional Pain Syndrome (CRPS) show reduced attention to the affected relative to unaffected limb and its surrounding space, resembling hemispatial neglect after brain injury. These neuropsychological symptoms could be related to central mechanisms of pathological pain and contribute to its clinical manifestation. However, the existing evidence of changes in spatial cognition is limited and often inconsistent. We examined visuospatial attention, the mental representation of space, and spatially-defined motor function in 54 people with unilateral upper-limb CRPS and 22 pain-free controls. Contrary to our hypotheses and previous evidence, individuals with CRPS did not show any systematic spatial biases in visuospatial attention to or representation of the side of space corresponding to their affected limb (relative to the unaffected side). We found very little evidence of directional slowing of movements towards the affected relative to unaffected side that would be consistent with motor neglect. People with CRPS were, however, slower than controls to initiate and execute movements with both their affected and unaffected hands, which suggests disrupted central motor networks. Finally, we found no evidence of any clinical relevance of changes in spatial cognition because there were no relationships between the magnitude of spatial biases and the severity of pain or other CRPS symptoms. The results did reveal potential relationships between CRPS pain and symptom severity, subjective body perception disturbance, and extent of motor impairment, which would support treatments focused on normalizing body representation and improving motor function. Our findings suggest that previously reported spatial biases in CRPS might have been overstated.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cortex.2020.02.018DOI Listing
June 2020

Altered updating of bodily and spatial representations after tool-use in complex regional pain syndrome.

Pain 2020 07;161(7):1609-1628

Centre for Pain Research, University of Bath, Bath, Somerset, United Kingdom.

Distorted representations of the body and peripersonal space are common in complex regional pain syndrome (CRPS), and might modulate its symptoms (eg, asymmetric limb temperature). In pain-free people, such representations are malleable, and update when we interact with objects in our environment (eg, during tool-use). Distortions are also common after immobilisation, but quickly normalise once movement is regained. We tested the hypothesis that people with CRPS have problems updating bodily and spatial representations, which contributes to the maintenance of their distorted representations by preventing normalization. We also explored spatially defined modulations of hand temperature asymmetries, and any influence of updating bodily and spatial representations on this effect. Thirty-six people with unilateral CRPS (18 upper limb and 18 lower limb) and 36 pain-free controls completed tool-use tasks considered to alter body and peripersonal space representations (measured using tactile distance judgements and a visuotactile crossmodal congruency task, respectively). We also tested how the arrangement (crossed and uncrossed) of the hands and tools affected hand temperature. In upper-limb CRPS, the nonaffected arm representation updated normally, but the affected arm representation updated in the opposite to normal direction. A similar pattern was seen in lower-limb CRPS, although not significant. Furthermore, people with CRPS showed more pronounced updating of peripersonal space than the controls. We did not observe any modulation of hand temperature asymmetries by the arrangement of hands or tools. Our findings show enhanced malleability of bodily and spatial representations in CRPS, which may suggest that central mechanisms are altered in this condition.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/j.pain.0000000000001845DOI Listing
July 2020

Pain reduction by inducing sensory-motor adaptation in Complex Regional Pain Syndrome (CRPS PRISMA): protocol for a double-blind randomized controlled trial.

BMC Neurol 2020 Feb 19;20(1):62. Epub 2020 Feb 19.

Centre for Pain Research, University of Bath, Claverton Down Road, Bath, BA2 7AY, UK.

Background: Complex Regional Pain Syndrome (CRPS) presents as chronic, continuous pain and sensory, autonomic, and motor abnormalities affecting one or more extremities. People with CRPS can also show changes in their perception of and attention to the affected body part and sensory information in the affected side of space. Prism Adaptation (PA) is a behavioural intervention targeted at reducing attention deficits in post-stroke hemispatial neglect. PA also appears to reduce pain and other CRPS symptoms; however, these therapeutic effects have been demonstrated only in small unblinded studies. This paper describes the protocol for an ongoing double-blind, randomized, sham-controlled clinical trial that will evaluate the efficacy of PA treatment for CRPS. The secondary aims of the study are to examine the relationships between neuropsychological changes (such as spatial attention, space and body representation, and motor spatial performance) and clinical manifestations of CRPS, as well as symptom improvement.

Methods: Forty-two participants with upper-limb CRPS type I will undergo 2 weeks of twice-daily PA treatment or sham treatment. The primary outcome measures are current pain intensity and CRPS severity score, measured immediately before and after the treatment period. Secondary outcome measures include the results of self-report questionnaires about pain, movement, symptoms interference, and body representation; clinical assessments of sensory, motor, and autonomic functions; and computer-based psychophysical tests of neuropsychological functions. Data are collected in four research visits: 4 weeks and 1 day before treatment, and 1 day and 4 weeks after the end of treatment. Additional follow-up through postal questionnaires is conducted 3 and 6 months post-treatment.

Discussion: It is hypothesised that participants undergoing PA treatment, compared to those receiving sham treatment, will show greater reduction in pain and CRPS severity score, and improvements on other clinical and neuropsychological measures. Also, more pronounced neuropsychological symptoms are predicted to correlate with more severe clinical CRPS symptoms. This study will provide the first randomized double-blind evaluation of the therapeutic effects of PA that could be implemented as a rehabilitation method for CRPS, and will contribute to the understanding of how neuropsychological changes in body representation and attention pertain to the manifestation and treatment of CRPS.

Trial Registration: (27/03/2017): ISRCTN46828292 (ISRCTN - ISRCTN46828292: Treatment of complex regional pain syndrome (CRPS) with sensory-motor adaptation).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12883-020-1604-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7031894PMC
February 2020

Experimentally induced pain does not influence updating of peripersonal space and body representations following tool-use.

PLoS One 2019 16;14(5):e0210045. Epub 2019 May 16.

Centre for Pain Research, University of Bath, Bath, Somerset, United Kingdom.

Representations of the body and peripersonal space can be distorted for people with some chronic pain conditions. Experimental pain induction can give rise to similar, but transient distortions in healthy individuals. However, spatial and bodily representations are dynamic, and constantly update as we interact with objects in our environment. It is unclear whether induced pain disrupts the mechanisms involved in updating these representations. In the present study, we sought to investigate the effect of induced pain on the updating of peripersonal space and body representations during and following tool-use. We compared performance under three conditions (pain, active placebo, neutral) on a visuotactile crossmodal congruency task and a tactile distance judgement task to measure updating of peripersonal space and body representations, respectively. Consistent with previous findings, the difference in crossmodal interference from visual distractors in the same compared to opposite visual field to the tactile target was less when tools were crossed than uncrossed. This suggests an extension of peripersonal space to incorporate the tips of the tools. Also consistent with previous findings, estimates of the felt tactile distance judgements decreased after active tool-use. In contrast to our predictions, however, we found no evidence that pain interfered with performance on either task when compared to the control conditions. Our findings suggest that the updating of peripersonal space and body representations is not disrupted by induced pain. That is, experiencing acute pain does not give rise to distorted representations of the body and peripersonal space that can be present in people with chronic pain conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0210045PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6522125PMC
January 2020

Dispositional Mindfulness and Psychological Health: a Systematic Review.

Mindfulness (N Y) 2018 1;9(1):23-43. Epub 2017 Jul 1.

Department of Psychology, University of Bath, BA2 7AY, 10W 3.51, Bath, UK.

Interest in the influence of dispositional mindfulness (DM) on psychological health has been gathering pace over recent years. Despite this, a systematic review of this topic has not been conducted. A systematic review can benefit the field by identifying the terminology and measures used by researchers and by highlighting methodological weaknesses and empirical gaps. We systematically reviewed non-interventional, quantitative papers on DM and psychological health in non-clinical samples published in English up to June 2016, following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A literature search was conducted using PsycINFO, PubMED, Medline and Embase, and 93 papers met the inclusion criteria. Within these, three main themes emerged, depicting the relationship between DM and psychological health: (1) DM appears to be inversely related to psychopathological symptoms such as depressive symptoms, (2) DM is positively linked to adaptive cognitive processes such as less rumination and pain catastrophizing and (3) DM appears to be associated with better emotional processing and regulation. These themes informed the creation of a taxonomy. We conclude that research has consistently shown a positive relationship between DM and psychological health. Suggestions for future research and conceptual and methodological limitations within the field are discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12671-017-0762-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5770488PMC
July 2017