Relative contributions of spatial weighting, explicit knowledge and proprioception to hand localisation during positional ambiguity.

When vision and proprioception are rendered incongruent during a hand localisation task, vision is initially weighted more than proprioception in determining location, and proprioception gains more weighting over time. However, it is not known whether, under these incongruency conditions, particular areas of space are also weighted more heavily than others, nor whether explicit knowledge of the sensory incongruence (i.e. disconfirming the perceived location of the hand) modulates the effect. Here, we hypothesised that both non-informative inputs coming from one side of space and explicit knowledge of sensory incongruence would modulate perceived location of the limb. Specifically, we expected spatial weighting to shift hand localisation towards the weighted area of space, and we expected greater weighting of proprioceptive input once perceived location was demonstrated to be inaccurate. We manipulated spatial weighting using an established auditory cueing paradigm (Experiment 1, n = 18) and sensory incongruence using the 'disappearing hand trick' (Experiment 2, n = 9). Our first hypothesis was not supported-spatial weighting did not modulate hand localisation. Our second hypothesis was only partially supported-disconfirmation of hand position did lead to more accurate localisations, even if participants were still unaware of their hand position. This raised the possibility that rather than disconfirmation, a simple movement of the hand in view could update the sensory-motor system, by immediately increasing the weighting of proprioceptive input relative to visual input. This third hypothesis was then confirmed (Experiment 3, n = 9). These results suggest that hand localisation is robust in the face of differential weighting of space, but open to modulation in a modality-specific manner, when one sense (vision) is rendered inaccurate.

Pain in elite athletes-neurophysiological, biomechanical and psychosocial considerations: a narrative review.

Pain is a common problem among elite athletes and is frequently associated with sport injury. Both injury and pain interfere with peak performance. Pain management should be based on the physiological, anatomical and psychosocial influences on the individual's pain and is not equivalent to injury management, which focuses on musculoskeletal recovery and return-to-play. This narrative review provides a foundation for understanding the differing causes and types of pain in elite athletes, thereby serving as a springboard for comprehensive pain management.

International Olympic Committee consensus statement on pain management in elite athletes.

Pain is a common problem among elite athletes and is frequently associated with sport injury. Both pain and injury interfere with the performance of elite athletes. There are currently no evidence-based or consensus-based guidelines for the management of pain in elite athletes. Typically, pain management consists of the provision of analgesics, rest and physical therapy. More appropriately, a treatment strategy should address all contributors to pain including underlying pathophysiology, biomechanical abnormalities and psychosocial issues, and should employ therapies providing optimal benefit and minimal harm. To advance the development of a more standardised, evidence-informed approach to pain management in elite athletes, an IOC Consensus Group critically evaluated the current state of the science and practice of pain management in sport and prepared recommendations for a more unified approach to this important topic.

Harnessing Children's Picture Books to Socialize Children About Pain and Injury: A Qualitative Study.

Pain experiences are common during childhood (eg, "everyday" pain, vaccine injections) and are powerful opportunities for children to learn about pain and injury. These experiences likely inform fundamental and life-long beliefs about pain. There is scant research investigating the sociocultural contexts in which children learn about pain and injury. One unexplored context is the shared reading of picture books (eg, between parents/caregivers and children). In this study, we investigated whether shared reading of picture books that included depictions of pain and/or injury prompted parent/caregiver-child interactions. If interactions were observed, we explored what those interactions entailed. Twenty parents/caregivers (8 men, 12 women) and their children (n = 27; 10 boys, 17 girls) were recruited from libraries in South Australia. Parent/caregiver-child families chose from 8 books (7 fiction, 1 nonfiction) with varying amounts of pain/injury-related content. Shared reading interactions were video recorded, transcribed, and analyzed alongside analysis of the picture books using reflexive thematic analysis. Pain/injury-related interactions were observed between parents/caregivers and children during shared reading of picture books. Qualitative analyses generated 1 main theme and 3 subthemes. Findings identified that shared reading presented an opportunity for children's understanding of pain and injury to be socialized through discussion of characters' experiences. This included teaching children about pain and injury, as well as promoting empathy and emotional attunement toward characters who were depicted as being in pain. Finally, parents/caregivers often responded with observable/expressed amusement if pain/injury was depicted in a light-hearted or unrealistic way. Overall, shared reading of picture books presents an untapped opportunity to socialize children about pain and injury. PERSPECTIVE: Shared reading of picture books that have depictions of pain and/or injury can prompt parent/caregiver-child interactions about pain and injury. These interactions present critical opportunities that can be harnessed to promote children's learning of adaptive pain-related concepts and behaviors during a critical developmental period.

We Are All in This Together-Whole of Community Pain Science Education Campaigns to Promote Better Management of Persistent Pain.

Persistent pain is a major public health issue-estimated to affect a quarter of the world's population. Public understanding of persistent pain is based on outdated biomedical models, laden with misconceptions that are contrary to best evidence. This understanding is a barrier to effective pain management. Thus, there have been calls for public health-based interventions to address these misconceptions. Previous pain-focussed public education campaigns have targeted pain beliefs and behaviours that are thought to promote recovery, such as staying active. However, prevailing pain-related misconceptions render many of these approaches counter-intuitive, at best. Pain Science Education improves understanding of 'how pain works' and has been demonstrated to improve pain and disability outcomes. Extending Pain Science Education beyond the clinic to the wider community seems warranted. Learning from previous back pain-focussed and other public health educational campaigns could optimise the potential benefit of such a Pain Science Education campaign. Pain Science Education-grounded campaigns have been delivered in Australia and the UK and show promise, but robust evaluations are needed before any firm conclusions on their population impact can be made. Several challenges exist going forward. Not least is the need to ensure all stakeholders are involved in the development and implementation of Pain Science Education public messaging campaigns. Furthermore, it is crucial that campaigns are undertaken through a health equity lens, incorporating underrepresented communities to ensure that any intervention does not widen existing health inequalities associated with persistent pain. PERSPECTIVE: Public misconceptions about pain are a significant public health challenge and a viable intervention target to reduce the personal, social, and economic burden of persistent pain. Adaptation of Pain Science Education, which improves misconceptions in a clinical setting, into the public health setting seems a promising approach to explore.

Teaching Patients About Pain: The Emergence of Pain Science Education, its Learning Frameworks and Delivery Strategies.

Since it emerged in the early 2000's, intensive education about 'how pain works', widely known as pain neuroscience education or explaining pain, has evolved into a new educational approach, with new content and new strategies. The substantial differences from the original have led the PETAL collaboration to call the current iteration 'Pain Science Education'. This review presents a brief historical context for Pain Science Education, the clinical trials, consumer perspective, and real-world clinical data that have pushed the field to update both content and method. We describe the key role of educational psychology in driving this change, the central role of constructivism, and the constructivist learning frameworks around which Pain Science Education is now planned and delivered. We integrate terminology and concepts from the learning frameworks currently being used across the PETAL collaboration in both research and practice-the Interactive, Constructive, Active, Passive framework, transformative learning theory, and dynamic model of conceptual change. We then discuss strategies that are being used to enhance learning within clinical encounters, which focus on the skill, will, and thrill of learning. Finally, we provide practical examples of these strategies so as to assist the reader to drive their own patient pain education offerings towards more effective learning. PERSPECTIVE: Rapid progress in several fields and research groups has led to the emergence 'Pain Science Education'. This PETAL review describes challenges that have spurred the field forward, the learning frameworks and educational strategies that are addressing those challenges, and some easy wins to implement and mistakes to avoid.

Spatially defined disruption of motor imagery performance in people with osteoarthritis.

OBJECTIVES: To determine whether motor imagery performance is disrupted in patients with painful knee OA and if this disruption is specific to the location of the pain. METHODS: Twenty patients with painful knee OA, 20 patients with arm pain and 20 healthy pain-free controls undertook a motor imagery task in which they made left/right judgements of pictured hands and feet. Accuracy and reaction time of judgements were compared between groups and pain locations (side: left vs right; site: upper vs lower). RESULTS: Patients with knee pain were less accurate (P < 0.01) than healthy controls, but not different from people with arm pain (all P > 0.11). There were no differences in reaction time between groups (P = 0.64). Further, there was no effect of side or site of pain on reaction time (P = 0.43, 0.54, respectively) and no effect of site of pain on accuracy of left/right judgements (P = 0.12). However, there was an interaction effect of side of pain on accuracy of left vs right images (P = 0.03). If left-sided pain was present, accuracy was lower when images showed left hands/feet than when images showed right hands/feet. CONCLUSION: Motor imagery performance is disrupted in patients with knee OA, but is also disrupted in patients with arm pain. Accuracy of left/right judgements is disrupted in a spatially defined manner, raising the important possibility that brain-grounded maps of peripersonal space contribute to the cortical proprioceptive representation.

Reliability and validity of a mobile tablet for assessing left/right judgements.

BACKGROUND: Left/right judgement (LRJ) of body parts is commonly used to assess the ability to perform implicit motor imagery and the integrity of brain-grounded maps of the body. Clinically, LRJ are often undertaken using a mobile tablet, but the concurrent validity and reliability of this approach has not yet been established. OBJECTIVES: To evaluate the concurrent validity and test-retest reliability of a mobile tablet for assessing LRJ. METHOD: Participants completed LRJ for 50 hand images (Experiment 1), and 40 back, foot, or neck images (Experiment 2) using a mobile tablet and desktop computer in random order. Participants in Experiment 2 performed a repeat test the following day to assess test-retest reliability. Accuracy and response time (RT) were recorded. RESULTS: Twenty participants aged 55.3 (±6.7) years in Experiment 1, and 37 participants aged 38.2 (±12.3) years in Experiment 2, were recruited. Concurrent validity of the mobile tablet was good to excellent for hand judgements (ICC3,1 = 0.836 for RT; ICC = 0.909 for accuracy), and was good for back, foot, and neck judgements (ICC = 0.781 for accuracy; ICC = 0.880 for RT). Test-retest reliability of the mobile tablet was good to excellent (ICC = 0.824 for accuracy; ICC = 0.903 for RT). CONCLUSIONS: The mobile tablet demonstrated good to excellent concurrent validity with the desktop computer in two separate samples. The mobile tablet also demonstrated good to excellent test-retest reliability. The mobile tablet for LRJ is a valid alternative to the original desktop version.

Non-informative vision enhances tactile acuity: A systematic review and meta-analysis.

BACKGROUND: Individual experimental data suggest that visual input during tactile stimulation enhances tactile appreciation - whether this finding is replicated across studies and across body sites is unknown. OBJECTIVE: To determine the available evidence as to whether non-informative vision of the body has an effect on tactile acuity. METHODS: Studies that assessed tactile acuity with vision of the body, compared to vision of a neutral object or vision occluded, were systematically identified and reviewed. Seven relevant electronic databases were searched from their inception to April 2014. Risk of bias was assessed using adapted criteria from the Cochrane Handbook. Effect sizes were calculated using mean differences in a random effects model. RESULTS: Ten studies were included. All were randomized, within subject, controlled trials published in English (total n=232 participants), with low to moderate risk of bias. Despite the diversity of protocols and outcome measures used, eight of the studies reported improvements in tactile acuity when vision of the relevant body part (predominantly the hand) was available. Meta-analysis revealed statistically significant findings from grating orientation tests (p=0.002, SMD 3.31, 95% CI 1.24-5.39), demonstrating a positive effect of vision of the body. No significant effect was found for other sensory tests or for other body parts, such as the back, and statistical heterogeneity was high. CONCLUSIONS: This review provides confirmatory evidence for a visual enhancement effect for tactile acuity for body parts where vision has a plausible functional linkage - further studies are required to elaborate on the mechanisms for multi-modal processing of sensory stimuli.

Generalization of Pain-Related Fear Using a Left-Right Hand Judgment Conditioning Task.

Recent research suggests that the mere intention to perform a painful movement can elicit pain-related fear. Based on these findings, the present study aimed to determine whether imagining a movement that is associated with pain (CS+) can start to elicit conditioned pain-related fear as well and whether pain-related fear elicited by imagining a painful movement can spread towards novel, similar but distinct imagined movements. We proposed a new experimental paradigm that integrates the left-right hand judgment task (HJT) with a differential fear conditioning procedure. During Acquisition, one hand posture (CS+) was consistently followed by a painful electrocutaneous stimulus (pain-US) and another hand posture (CS-) was not. Participants were instructed to make left-right judgments, which involve mentally rotating their own hand to match the displayed hand postures (i.e., motor imagery). During Generalization, participants were presented with a series of novel hand postures with six grades of perceptual similarity to the CS+ (generalization stimuli; GSs). Finally, during Extinction, the CS+ hand posture was no longer reinforced. The results showed that (1) a painful hand posture triggers fear and increased US-expectancy as compared to a nonpainful hand posture, (2) this pain-related fear spreads to similar but distinct hand postures following a generalization gradient, and subsequently, (3) it can be successfully reduced during extinction. These effects were apparent in the verbal ratings, but not in the startle measures. Because of the lack of effect in the startle measures, we cannot draw firm conclusions about whether the "imagined movements" (i.e., motor imagery of the hand postures) gained associative strength rather than the hand posture pictures itself. From a clinical perspective, basic research into generalization of pain-related fear triggered by covert CSs such as intentions, imagined movements and movement-related cognitions might further our understanding of how pain and fear avoidance spread and persevere.

Effects of experimentally induced pain and fear of pain on trunk coordination and back muscle activity during walking.

OBJECTIVE: To examine the effects of experimentally induced pain and fear of pain on trunk coordination and erector spinae EMG activity during gait. DESIGN: In 12 healthy subjects, hypertonic saline (acute pain) and isotonic saline (fear of pain) were injected into erector spinae muscle, and unpredictable electric shocks (fear of impending pain) were presented during treadmill walking at different velocities, while trunk kinematics and EMG were recorded. BACKGROUND: Chronic low back pain patients often have disturbed trunk coordination and enhanced erector spinae EMG while walking, which may either be due to the pain itself or to fear of pain, as is suggested by studies on both low back pain patients and healthy subjects. METHODS: The effects of the aforementioned pain-related manipulations on trunk coordination and EMG were examined. Results. Trunk kinematics was not affected by the manipulations. Induced pain led to an increase in EMG variability and induced fear of pain to a decrease in mean EMG amplitude during double stance. CONCLUSIONS: Induced pain and fear of pain have subtle effects on erector spinae EMG activity during walking while leaving the global pattern of EMG activity and trunk kinematics unaffected. This suggests that the altered gait observed in low back pain patients is probably a complex evolved consequence of a lasting pain, rather than a simple immediate effect. RELEVANCE: Variability of EMG data and kinematics may explain pain-dependent alterations of motor control, which in turn might contribute to a further understanding of the development of movement impairments in low back pain.

Evidence for working memory deficits in chronic pain: a systematic review and meta-analysis.

People with chronic pain commonly report impaired cognitive function. However, to date, there has been no systematic evaluation of the body of literature concerning cognitive impairment and pain. Nor have modern meta-analytical methods been used to verify and clarify the extent to which cognition may be impaired. The objective of this study was to systematically evaluate and critically appraise the literature concerning working memory function in people with chronic pain. The study was conducted along Cochrane collaboration and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. A sensitive search strategy was designed and conducted with the help of an expert librarian using 6 databases. Twenty-four observational studies evaluating behavioural and/or physiological outcomes in a chronic pain group and a control group met the inclusion criteria. All studies had a high risk of bias, owing primarily to lack of assessor blinding to outcome. High heterogeneity within the field was found with the inclusion of 24 papers using 21 different working memory tests encompassing 9 different working memory constructs and 9 different chronic pain populations. Notwithstanding high heterogeneity, pooled results from behavioural outcomes reflected a consistent, significant moderate effect in favour of better performance by healthy controls and, with the exception of one study, pooled results from physiological outcomes reflected no evidence for an effect. Future research would benefit from the use of clearly defined constructs of working memory, as well as standardised methods of testing.

Dysynchiria is not a common feature of neuropathic pain.

Patients with chronic neuropathic pain (non-CRPS) and brush-evoked allodynia watched a reflected image of their corresponding but opposite skin region being brushed in a mirror. Unlike complex regional pain syndrome Type 1, this process did not evoke any sensation at the affected area ('dysynchiria'). We conclude that central nociceptive sensitisation alone is not sufficient to cause dysynchiria in neuropathic pain. The results imply a difference in cortical pain processing between complex regional pain syndrome and other chronic neuropathic pain.