Multisensory processing and proprioceptive plasticity during resizing illusions.

Bodily resizing illusions typically use visual and/or tactile inputs to produce a vivid experience of one's body changing size. Naturalistic auditory input (an input that reflects the natural sounds of a stimulus) has been used to increase illusory experience during the rubber hand illusion, whilst non-naturalistic auditory input can influence estimations of finger length. We aimed to use a non-naturalistic auditory input during a hand-based resizing illusion using augmented reality, to assess whether the addition of an auditory input would increase both subjective illusion strength and measures of performance-based tasks. Forty-four participants completed the following three conditions: no finger stretching, finger stretching without tactile feedback and finger stretching with tactile feedback. Half of the participants had an auditory input throughout all the conditions, whilst the other half did not. After each condition, the participants were given one of the following three performance tasks: stimulated (right) hand dot touch task, non-stimulated (left) hand dot touch task, and a ruler judgement task. Dot tasks involved participants reaching for the location of a virtual dot, whereas the ruler task concerned estimates of the participant's own finger on a ruler whilst the hand was hidden from view. After all trials, the participants completed a questionnaire capturing subjective illusion strength. The addition of auditory input increased subjective illusion strength for manipulations without tactile feedback but not those with tactile feedback. No facilitatory effects of audio were found for any performance task. We conclude that adding auditory input to illusory finger stretching increased subjective illusory experience in the absence of tactile feedback but did not affect performance-based measures.

Changing hands: persistent alterations to body image following brief exposure to multisensory distortions.

The dynamic flexibility of body representation has been highlighted through numerous lines of research that range from clinical studies reporting disorders of body ownership, to experimentally induced somatic illusions that have provided evidence for the embodiment of manipulated representations and even fake limbs. While most studies have reported that enlargement of body parts alters somatic perception, and that these can be more readily embodied, shrunken body parts have not been found to consistently alter somatic experiences, perhaps due to reduced feelings of ownership over smaller body parts. Over two experiments, we aimed to investigate the mechanisms responsible for altered somatic representations following exposure to both enlarged and shrunken body parts. Participants were given the impression that their hand and index finger were either longer or shorter than veridical length and asked to judge veridical finger length using online and offline size estimation tasks, as well as to report the degree of ownership towards the distorted finger and hand representations. Ownership was claimed over all distorted representations of the hand and finger and no differences were seen across ownership ratings, while the online and offline measurements of perceived size demonstrated differing response patterns. These findings suggest that ownership towards manipulated body representations is more bidirectional than previously thought and also suggest differences in perceived body representation with respect to the method of measurement suggesting that online and offline tasks may tap into different aspects of body representation.

Multisensory distortions of the hand have differential effects on tactile perception.

Research has suggested that altering the perceived shape and size of the body image significantly affects perception of somatic events. The current study investigated how multisensory illusions applied to the body altered tactile perception using the somatic signal detection task. Thirty-one healthy volunteers were asked to report the presence or absence of near-threshold tactile stimuli delivered to the index finger under three multisensory illusion conditions: stretched finger, shrunken finger and detached finger, as well as a veridical baseline condition. Both stretching and shrinking the stimulated finger enhanced correct touch detections; however, the mechanisms underlying this increase were found to be different. In contrast, the detached appearance reduced false touch reports-possibly due to reduced tactile noise, as a result of attention being directed to the tip of the finger only. These findings suggest that distorted representations of the body could have different modulatory effects on attention to touch and provide a link between perceived body representation and somatosensory decision-making.

Distinct neural signatures of multimodal resizing illusions.

Illusory body resizing typically uses multisensory integration to change the perceived size of a body part. Previous studies associate these multisensory body illusions with frontal theta oscillations and parietal gamma oscillations for dis-integration and integration of multisensory signals, respectively. However, recent studies also support illusory changes of embodiment from unimodal visual stimuli. This preregistered study (N = 48) investigated differences between multisensory visuo-tactile and unimodal visual resizing illusions using EEG, to gain a more comprehensive understanding of the neural underpinnings of resizing illusions in a healthy population. We hypothesised (1) stronger illusion in multisensory compared to unimodal, and unimodal compared to incongruent (dis-integration) conditions, (2) greater parietal gamma during multisensory compared to unimodal, and (3) greater frontal theta during incongruent compared to baseline conditions. Subjective Illusory results partially support Hypothesis 1, showing a stronger illusion in multisensory compared to unimodal conditions, but finding no significant difference comparing unimodal to incongruent conditions. Results partially supported EEG hypotheses, finding increased parietal gamma activity comparing multisensory to unimodal visual conditions, happening at a later stage of the illusion when compared to previous rubber hand illusion EEG findings, whilst also finding increased parietal theta activity when comparing incongruent to non-illusion conditions. While results demonstrated that only 27% of participants experienced the stretching illusion with unimodal visual stimuli compared to 73% of participants experiencing the stretching illusion in the multisensory condition, further analysis suggested that those who experience visual-only illusions exhibit a different neural signature to those who do not, with activity focussed around frontal and parietal regions early on in the illusory manipulation, compared to activity focussed more over parietal regions and at a later point in the illusory manipulation for the full sample of participants. Our results replicate previous subjective experience findings and support the importance of multisensory integration for illusory changes in perceived body size, whilst adding to our understanding of the temporal onset of multisensory integration within resizing illusions, differing from that of rubber hand illusions.

Classifying external causes of injury: history, current approaches, and future directions.

The International Classification of Diseases (ICD) is used to categorize diseases, injuries, and external causes of injury, and it is a key epidemiologic tool enabling storage and retrieval of data from health and vital records to produce core international mortality and morbidity statistics. The ICD is updated periodically to ensure the classification system remains current, and work is now under way to develop the next revision, ICD-11. It has been almost 20 years since the last ICD edition was published and over 60 years since the last substantial structural revision of the external causes chapter. Revision of such a critical tool requires transparency and documentation to ensure that changes made to the classification system are recorded comprehensively for future reference. In this paper, the authors provide a history of the development of external causes classification and outline the external cause structure. They discuss approaches to manage ICD-10 deficiencies and outline the ICD-11 revision approach regarding the development of, rationale for, and implications of proposed changes to the chapter. Through improved capture of external cause concepts in ICD-11, a stronger evidence base will be available to inform injury prevention, treatment, rehabilitation, and policy initiatives to ultimately contribute to a reduction in injury morbidity and mortality.

Physical symptom reporting is associated with a tendency to experience somatosensory distortion.

OBJECTIVE: Theory suggests that a tendency to experience distortions in somatosensory awareness is associated with physical symptom reporting (i.e., somatization) but empirical evidence for this is lacking. This article describes research designed to test this hypothesis. METHODS: Somatosensory distortion was operationalized as the frequency of illusory touch experiences (i.e., false alarm rate) on the Somatic Signal Detection Task. Two studies correlated false alarms on this task with physical symptom reporting on the 15-item Patient Health Questionnaire, the first using a nonclinical sample (n = 35), the second using a clinical sample of endoscopy patients who were identified as having either medically explained (n = 25) or medically unexplained symptoms (n = 30). RESULTS: Scores on the 15-item Patient Health Questionnaire were positively correlated with false alarm rate in both studies (r = 0.288-0.506), even after controlling for trait anxiety, depression, anxiety (standardized ß range = 0.793-0.932, all p < .0001) and (in Study 2) somatosensory amplification and hypochondriacal worry (standardized ß range = 0.345-0.375, both p < .05). There was no difference in false alarm rate between patients with medically explained and medically unexplained symptoms (medically explained median range = 6.8 [3.7] to 6.8 [4.0] versus medically unexplained median range = 4.3 [3.9] to 5.6 [3.1], both p > .1). CONCLUSIONS: There seems to be a robust link between physical symptom reporting and the tendency to experience somatosensory distortion, consistent with recent cognitive theories. It may be possible to reduce the impact of somatization by developing treatments that target this tendency.

Assessing the concordance of health and child protection data for 'maltreated' and 'unintentionally injured' children.

OBJECTIVES: To quantify the concordance of hospital child maltreatment data with child protection service (CPS) records, and identify factors associated with linkage. METHODS: Multivariable logistic regression analysis was conducted following retrospective medical record review and database linkage of 884 child records from 20 hospitals and the CPS in Queensland, Australia. RESULTS: Nearly all children with hospital assigned maltreatment codes (93.1%) had a CPS record. Of these, 85.1% had a recent notification. 29% of the linked maltreatment group (n=113) were not known to the CPS prior to the hospital presentation. Almost one third of children with unintentional injury hospital codes were known to the CPS. Just over 24% of the linked unintentional injury group (n=34) were not known to the CPS prior to the hospital presentation but became known during or after discharge from hospital. These estimates are higher than the 2006/2007 annual rate of 2.39% of children being notified to the CPS. Rural children were more likely to link to the CPS, and children were over three times more likely to link if the index injury documentation included additional diagnoses or factors affecting their health. CONCLUSIONS: The system for referring maltreatment cases to the CPS is generally efficient, although up to 1 in 15 children had codes for maltreatment but could not be linked to CPS data. The high proportion of children with unintentional injury codes who linked to CPS suggests that clinicians and hospital-based child protection staff should be supported by further education and training to ensure children at risk are being detected by the child protection system.

Quantity of documentation of maltreatment risk factors in injury-related paediatric hospitalisations.

BACKGROUND: While child maltreatment is recognised as a global problem, solid epidemiological data on the prevalence of child maltreatment and risk factors associated with child maltreatment is lacking in Australia and internationally. There have been recent calls for action to improve the evidence-base capturing and describing child abuse, particularly those data captured within the health sector. This paper describes the quantity of documentation of maltreatment risk factors in injury-related paediatric hospitalisations in Queensland, Australia. METHODS: This study involved a retrospective medical record review, text extraction and coding methodology to assess the quantity of documentation of risk factors and the subsequent utility of data in hospital records for describing child maltreatment and data linkage to Child Protection Service (CPS). RESULTS: There were 433 children in the maltreatment group and 462 in the unintentional injury group for whom medical records could be reviewed. Almost 93% of the maltreatment code sample, but only 11% of the unintentional injury sample had documentation identified indicating the presence of any of 20 risk factors. In the maltreatment group the most commonly documented risk factor was history of abuse (41%). In those with an unintentional injury, the most commonly documented risk factor was alcohol abuse of the child or family (3%). More than 93% of the maltreatment sample also linked to a child protection record. Of concern are the 16% of those children who linked to child protection who did not have documented risk factors in the medical record. CONCLUSION: Given the importance of the medical record as a source of information about children presenting to hospital for treatment and as a potential source of evidence for legal action the lack of documentation is of concern. The details surrounding the injury admission and consideration of any maltreatment related risk factors, both identifying their presence and ruling them out are required for each and every case. This highlights the need for additional training for clinicians to understand the importance of their documentation in child injury cases.

Using routinely collected hospital data for child maltreatment surveillance: issues, methods and patterns.

BACKGROUND: International data on child maltreatment are largely derived from child protection agencies, and predominantly report only substantiated cases of child maltreatment. This approach underestimates the incidence of maltreatment and makes inter-jurisdictional comparisons difficult. There has been a growing recognition of the importance of health professionals in identifying, documenting and reporting suspected child maltreatment. This study aimed to describe the issues around case identification using coded morbidity data, outline methods for selecting and grouping relevant codes, and illustrate patterns of maltreatment identified. METHODS: A comprehensive review of the ICD-10-AM classification system was undertaken, including review of index terms, a free text search of tabular volumes, and a review of coding standards pertaining to child maltreatment coding. Identified codes were further categorised into maltreatment types including physical abuse, sexual abuse, emotional or psychological abuse, and neglect. Using these code groupings, one year of Australian hospitalisation data for children under 18 years of age was examined to quantify the proportion of patients identified and to explore the characteristics of cases assigned maltreatment-related codes. RESULTS: Less than 0.5% of children hospitalised in Australia between 2005 and 2006 had a maltreatment code assigned, almost 4% of children with a principal diagnosis of a mental and behavioural disorder and over 1% of children with an injury or poisoning as the principal diagnosis had a maltreatment code assigned. The patterns of children assigned with definitive T74 codes varied by sex and age group. For males selected as having a maltreatment-related presentation, physical abuse was most commonly coded (62.6% of maltreatment cases) while for females selected as having a maltreatment-related presentation, sexual abuse was the most commonly assigned form of maltreatment (52.9% of maltreatment cases). CONCLUSION: This study has demonstrated that hospital data could provide valuable information for routine monitoring and surveillance of child maltreatment, even in the absence of population-based linked data sources. With national and international calls for a public health response to child maltreatment, better understanding of, investment in and utilisation of our core national routinely collected data sources will enhance the evidence-base needed to support an appropriate response to children at risk.

Reliability of routinely collected hospital data for child maltreatment surveillance.

BACKGROUND: Internationally, research on child maltreatment-related injuries has been hampered by a lack of available routinely collected health data to identify cases, examine causes, identify risk factors and explore health outcomes. Routinely collected hospital separation data coded using the International Classification of Diseases and Related Health Problems (ICD) system provide an internationally standardised data source for classifying and aggregating diseases, injuries, causes of injuries and related health conditions for statistical purposes. However, there has been limited research to examine the reliability of these data for child maltreatment surveillance purposes. This study examined the reliability of coding of child maltreatment in Queensland, Australia. METHODS: A retrospective medical record review and recoding methodology was used to assess the reliability of coding of child maltreatment. A stratified sample of hospitals across Queensland was selected for this study, and a stratified random sample of cases was selected from within those hospitals. RESULTS: In 3.6% of cases the coders disagreed on whether any maltreatment code could be assigned (definite or possible) versus no maltreatment being assigned (unintentional injury), giving a sensitivity of 0.982 and specificity of 0.948. The review of these cases where discrepancies existed revealed that all cases had some indications of risk documented in the records. 15.5% of cases originally assigned a definite or possible maltreatment code, were recoded to a more or less definite strata. In terms of the number and type of maltreatment codes assigned, the auditor assigned a greater number of maltreatment types based on the medical documentation than the original coder assigned (22% of the auditor coded cases had more than one maltreatment type assigned compared to only 6% of the original coded data). The maltreatment types which were the most 'under-coded' by the original coder were psychological abuse and neglect. Cases coded with a sexual abuse code showed the highest level of reliability. CONCLUSION: Given the increasing international attention being given to improving the uniformity of reporting of child-maltreatment related injuries and the emphasis on the better utilisation of routinely collected health data, this study provides an estimate of the reliability of maltreatment-specific ICD-10-AM codes assigned in an inpatient setting.

The population approach to falls injury prevention in older people: findings of a two community trial.

BACKGROUND: There is a sound rationale for the population-based approach to falls injury prevention but there is currently insufficient evidence to advise governments and communities on how they can use population-based strategies to achieve desired reductions in the burden of falls-related injury. The aim of the study was to quantify the effectiveness of a streamlined (and thus potentially sustainable and cost-effective), population-based, multi-factorial falls injury prevention program for people over 60 years of age. METHODS: Population-based falls-prevention interventions were conducted at two geographically-defined and separate Australian sites: Wide Bay, Queensland, and Northern Rivers, NSW. Changes in the prevalence of key risk factors and changes in rates of injury outcomes within each community were compared before and after program implementation and changes in rates of injury outcomes in each community were also compared with the rates in their respective States. RESULTS: The interventions in neither community substantially decreased the rate of falls-related injury among people aged 60 years or older, although there was some evidence of reductions in occurrence of multiple falls reported by women. In addition, there was some indication of improvements in fall-related risk factors, but the magnitudes were generally modest. CONCLUSIONS: The evidence suggests that low intensity population-based falls prevention programs may not be as effective as those that are intensively implemented.

Identifying work related injuries: comparison of methods for interrogating text fields.

BACKGROUND: Work-related injuries in Australia are estimated to cost around $57.5 billion annually, however there are currently insufficient surveillance data available to support an evidence-based public health response. Emergency departments (ED) in Australia are a potential source of information on work-related injuries though most ED's do not have an 'Activity Code' to identify work-related cases with information about the presenting problem recorded in a short free text field. This study compared methods for interrogating text fields for identifying work-related injuries presenting at emergency departments to inform approaches to surveillance of work-related injury. METHODS: Three approaches were used to interrogate an injury description text field to classify cases as work-related: keyword search, index search, and content analytic text mining. Sensitivity and specificity were examined by comparing cases flagged by each approach to cases coded with an Activity code during triage. Methods to improve the sensitivity and/or specificity of each approach were explored by adjusting the classification techniques within each broad approach. RESULTS: The basic keyword search detected 58% of cases (Specificity 0.99), an index search detected 62% of cases (Specificity 0.87), and the content analytic text mining (using adjusted probabilities) approach detected 77% of cases (Specificity 0.95). CONCLUSIONS: The findings of this study provide strong support for continued development of text searching methods to obtain information from routine emergency department data, to improve the capacity for comprehensive injury surveillance.

Distorted body image influences body schema in individuals with negative bodily attitudes.

There is now a considerable body of evidence to suggest that internal representations of the body can be meaningfully separated into at least two general levels; body image as a perceptual construct and body schema as a motor metric. However, recent studies with eating disordered individuals have suggested that there may in fact be more interaction between these two representations than first thought. We aimed to investigate how body image might act to influence body schema within a typical, healthy population. 100 healthy adult women were asked to judge the smallest gap between a pair of sliding doors that they could just pass through. We then determined whether these estimates were sufficient to predict the size of the smallest gap that they could actually pass through, or whether perceptual and attitudinal body image information was required in order to make these predictions. It was found that perceptual body image did indeed mediate performance on the egocentric (but not allocentric) motor imagery affordance task, but only for those individuals with raised body image concerns and low self-esteem; body schema was influenced by both the perceptual and attitudinal components of body image in those with more negative bodily attitudes. Furthermore, disparities between perceived versus actual size were associated with body parts that had larger variations in adipose/muscle-dependent circumference. We therefore suggest that it may be the affective salience of a distorted body representation that mediates the degree to which it is incorporated into the current body state.

Coding external causes of injuries: problems and solutions.

Complete and accurate information about hospitalised injuries is essential for injury risk and outcome research, though the accuracy and reliability of hospital data for injury surveillance are often questioned. To ascertain clinical coders' views of the reasons for a lack of specificity in external cause code usage and ways to improve external cause coding, a nationwide survey of coders was conducted in Australia in 2006. Four hundred and two coders participated in the questionnaire. The results of this study show that discharge summaries and doctors' notes were the poorest source of information regarding external causes, place of injury occurrence, and activity at the time of injury. Coders viewed missing external cause information and missing documentation as having the greatest impact on the quality of external cause coding. A large majority of coders suggested that improving clinical documentation in the emergency department and introducing a centralised structured form for external cause information would improve the quality of external cause coding. Clinical coders are a valuable source of information regarding problems with, and solutions to the collection of high quality data and this research has highlighted several areas where improvements can be made and further research is needed.

Vimentin Diversity in Health and Disease.

Vimentin is a protein that has been linked to a large variety of pathophysiological conditions, including cataracts, Crohn's disease, rheumatoid arthritis, HIV and cancer. Vimentin has also been shown to regulate a wide spectrum of basic cellular functions. In cells, vimentin assembles into a network of filaments that spans the cytoplasm. It can also be found in smaller, non-filamentous forms that can localise both within cells and within the extracellular microenvironment. The vimentin structure can be altered by subunit exchange, cleavage into different sizes, re-annealing, post-translational modifications and interacting proteins. Together with the observation that different domains of vimentin might have evolved under different selection pressures that defined distinct biological functions for different parts of the protein, the many diverse variants of vimentin might be the cause of its functional diversity. A number of review articles have focussed on the biology and medical aspects of intermediate filament proteins without particular commitment to vimentin, and other reviews have focussed on intermediate filaments in an in vitro context. In contrast, the present review focusses almost exclusively on vimentin, and covers both ex vivo and in vivo data from tissue culture and from living organisms, including a summary of the many phenotypes of vimentin knockout animals. Our aim is to provide a comprehensive overview of the current understanding of the many diverse aspects of vimentin, from biochemical, mechanical, cellular, systems biology and medical perspectives.

Parietal updating of limb posture: an event-related fMRI study.

The posterior parietal cortex (PPC) is thought to integrate different kinds of sensory information (e.g., visual, auditory, somatosensory) to produce multiple representations of space that are each associated with different types or combinations of action; such as saccadic eye movements and reaching or grasping movements of the upper limb. Lesion studies in monkeys and in humans have shown that reaching movements to visually defined and to posturally defined targets can be dissociated from one another; indicating that different regions of the parietal cortex may code the same movement in either extrinsic (visual) or intrinsic (postural) coordinates. These studies also suggest that regions within the posterior parietal cortex play an important role in maintaining an accurate and up-to-date representation of the current postural state of the body (the body schema). We used event-related functional magnetic resonance imaging (fMRI) to investigate those brain areas involved in maintaining and updating postural (i.e., non-visual) representations of the upper limb that participate in the accurate control of reaching movements. We show that a change in the posture of the upper-limb is associated with a significant increase in BOLD activation in only one brain region--the superior parietal cortex, particularly the medial aspect (precuneus). We note that this finding is consistent with the suggestion, based upon human neurological investigations and monkey electrophysiology, that this region of the PPC may participate in the dynamic representation of the body schema, and is the most likely location for damage leading to errors in visually guided reaching to non-foveated target locations. We also note that this brain area corresponds to a region of PPC recently identified as the human homologue of the Parietal Reach Region (PRR) observed in the monkey brain that has been thought to represent reaching movements in eye-centred coordinates.

The quality of cause-of-injury data: where hospital records fall down.

OBJECTIVES: This research identifies the level of specificity of cause-of-injury morbidity data in Australia. The research explores reasons for poor-quality data across different causes-of-injury areas, including a lack of clinical documentation and insufficient detail in the classification system. METHODS: The 2002/03 hospital morbidity dataset of 593,079 injury-related hospital admissions was analysed to examine the specificity of coded external cause-of-injury data. RESULTS: While overall specificity appeared high, the cause of 47,660 injuries was not specifically defined according to the code assigned. Only 56% of cases for whom injury was the result of an accidental fall were assigned a specific code to identify the causal detail; 19% were assigned an 'Other Specified' fall code, suggesting a lack of specific code availability; and 25% were assigned an 'Unspecified Fall' code, suggesting a lack of clinical documentation to facilitate code selection. CONCLUSIONS: To improve the quality of injury-related hospital morbidity data, two main areas to focus resources are: 1) the development of more specific cause-of-injury codes; and 2) the provision of more detailed documentation from clinicians. IMPLICATIONS: Clinicians and clinical coders need to work together to improve the quality of injury-related coded data through the provision of specific codes and improved clinical documentation. Accurate and comprehensive data pertaining to the circumstances surrounding hospitalised injury events will benefit injury prevention and surveillance initiatives, provide justification for resources related to injury hospitalisation, and assist in external cause research in Australia.

Increased somatic sensations are associated with reduced limb ownership.

OBJECTIVE: Medically unexplained symptoms (MUS) are increasingly being thought of as resulting from dysfunctional modulation of interoceptive sensory signals by top-down cognitive processes. The current study investigated whether individuals with a tendency toward MUS would be more susceptible to visual illusions that suggest tactile sensation on the skin in the absence of any actual somatosensory input. METHOD: Participants viewed real-time-mediated reality video images of their own hand, either un-manipulated or digitally altered to display moving pixelated 'static' effect, the crawling skin illusion. The strength of various physical sensations during each condition were rated on a numeric scale and compared to standard measures of somatoform dissociation (Somatoform Dissociation Questionnaire 20). RESULTS: Participants reporting a higher degree of somatoform dissociation were found to be more susceptible to somatic sensations across all conditions. Interestingly, participants who reported more visually induced somatosensory sensations also felt less ownership over their digitally presented hands. CONCLUSION: These findings support the proposed link between MUS and disturbances in body representation, and suggest that an over-reliance on top-down knowledge may interfere with current sensory inputs, contributing to symptom formation and maintenance in susceptible individuals.

Cerebral asymmetry for mental rotation: effects of response hand, handedness and gender.

We assessed lateralization of brain function during mental rotation, measuring the scalp distribution of a 400-600 ms latency event-related potential (ERP) with 128 recording electrodes. Twenty-four subjects, consisting of equal numbers of dextral and sinistral males and females, performed a mental rotation task under two response conditions (dominant non-dominant hand). For males, ERPs showed a right parietal bias regardless of response hand. For females, the parietal ERPs were slightly left-lateralized when making dominant hand responses, but strongly right-lateralized when making non-dominant hand responses. These results support the notion that visuo-spatial processing is more bilaterally organized in females. However, left hemisphere resources may be allocated to response preparation when using the non-dominant hand, forcing visuo-spatial processing to the right hemisphere.