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Previous behavioral studies reported a robust effect of increased naming latencies when objects to be named were blocked within semantic category, compared to items blocked between category. This semantic context effect has been attributed to various mechanisms including inhibition or excitation of lexico-semantic representations and incremental learning of associations between semantic features and names, and is hypothesized to increase demands on verbal self-monitoring during speech production. Objects within categories also share many visual structural features, introducing a potential confound when interpreting the level at which the context effect might occur. Consistent with previous findings, we report a significant increase in response latencies when naming categorically related objects within blocks, an effect associated with increased perfusion fMRI signal bilaterally in the hippocampus and in the left middle to posterior superior temporal cortex. No perfusion changes were observed in the middle section of the left middle temporal cortex, a region associated with retrieval of lexical-semantic information in previous object naming studies. Although a manipulation of visual feature similarity did not influence naming latencies, we observed perfusion increases in the perirhinal cortex for naming objects with similar visual features that interacted with the semantic context in which objects were named. These results provide support for the view that the semantic context effect in object naming occurs due to an incremental learning mechanism, and involves increased demands on verbal self-monitoring.

This fMRI study investigates how audiovisual integration differs for verbal stimuli that can be matched at a phonological level and nonverbal stimuli that can be matched at a semantic level. Subjects were presented simultaneously with one visual and one auditory stimulus and were instructed to decide whether these stimuli referred to the same object or not. Verbal stimuli were simultaneously presented spoken and written object names, and nonverbal stimuli were photographs of objects simultaneously presented with naturally occurring object sounds. Stimulus differences were controlled by including two further conditions that paired photographs of objects with spoken words and object sounds with written words. Verbal matching, relative to all other conditions, increased activation in a region of the left superior temporal sulcus that has previously been associated with phonological processing. Nonverbal matching, relative to all other conditions, increased activation in a right fusiform region that has previously been associated with structural and conceptual object processing. Thus, we demonstrate how brain activation for audiovisual integration depends on the verbal content of the stimuli, even when stimulus and task processing differences are controlled. (Contains 4 figures and 4 tables.)

Objective: To evaluate the Canadian Syncope Risk Score (CSRS) in syncope patients presenting to the ED from an economic perspective, using very‐low and low‐risk patients (CSRS −3 to 0) as a threshold for avoiding hospital admissions. Methods: A decision‐analytic model, specifically a decision‐tree, was developed to evaluate application of the CSRS. A hypothetical cohort of 1000 patients was modelled based on characteristics and outcome of patients enrolled in a clinical validation study performed alongside this evaluation. Several analytic based approaches were used to handle model outputs and uncertainties. Results: For a cohort of 1000 patients, applying the CSRS was associated with 169 less inpatient admissions from the ED, when compared to usual care. There was also a cost‐saving of $8255 per admitted patient, when the CSRS was applied, compared to usual care. Adopting the CSRS was the optimal approach in all scenario analyses and was robust to changes in model parameters. More than three‐quarters (78.6%) of all model simulations showed that applying the CSRS is a cost‐saving approach to managing syncope. There was high confidence in all results, with the approach using the CSRS reducing the costs and number of syncope‐related hospital admissions. Conclusions: Compared to usual care, applying the CSRS appeared as a cost‐effective strategy. This new evidence will help decision‐makers choose cost‐effective approaches for the management of patients presenting to the ED with syncope, as they search for efficient ways to maximise health gain from a finite budget. [ABSTRACT FROM AUTHOR]

Objective: To investigate the experience of nurses involved in decision‐making to transfer residents from a residential aged care facility (RACF) to their local hospital emergency department. This paper reports on the findings of the second phase of a two‐phase study. Methods: Qualitative semi‐structured interviews with 19 aged care nurses were conducted. Interviews were audio‐taped and transcribed verbatim, and a thematic analysis was carried out. Results: The analysis revealed five major themes that influenced decision‐making in relation to the transfer of a resident from the residential aged care facility to the emergency department: conflict with key stakeholders; knowledge and experience; policy and process; stakeholder perception; and recognition and support. Conclusions: Robust outreach programs, support from other health‐care professionals, and improving interdisciplinary understanding and communication between aged care nurses, paramedics and the emergency department would be advantageous to ensure effective care delivery and decision‐making. [ABSTRACT FROM AUTHOR]

Objective: This study aims to determine whether redeploying junior doctors to assist at triage represents good value for money and a good use of finite staffing resources. Methods: We undertook a cost-minimisation analysis to produce new evidence, from an economic perspective, about the costs associated with reallocating junior doctors in the emergency department. We built a decision-analytic model, using a mix of prospectively collected data, routinely collected administrative databases and hospital costings to furnish the model. To measure the impact of uncertainty on the model's inputs and outputs, probabilistic sensitivity analysis was undertaken, using Monte Carlo simulation. Results: The mean costs for usual care were $27,035 (95% CI $27,016 to $27,054), while the mean costs for the new model of care were $25,474, (95% CI $25,453 to $25,494). As a result, the mean difference was -$1,561 (95% CI -$1,533 to -$1,588), with the new model of care being a less costly approach to managing staffing allocations, in comparison to the usual approach. Conclusion: Our study shows that redeploying a junior doctor from the fast-track area of the department to assist at triage provides a modest reduction in cost. Our findings give decision-makers who seek to maximise benefit from their finite budget, support to reallocate personnel within the ED. [ABSTRACT FROM AUTHOR]

Objective: To validate the accuracy and safety of the Canadian Syncope Risk Score (CSRS) for patients presenting with syncope. Methods: Single centre prospective observational study in Brisbane, Australia. Adults presenting to the ED with syncope within the last 24 h were recruited after applying exclusion criteria. Study was conducted over 1 year, from March 2018 to March 2019. Thirty‐day serious adverse events (SAE) were reported based on the original derivation study and standardised outcome reporting for syncope. Individual patient CSRS was calculated and correlated with 30‐day SAE and disposition status from ED. Results: Two hundred and eighty‐three patients were recruited to the study. Average age was 55.6 years (SD 22.7 years), 37.1% being male with a 39.9% admission rate. Thirty‐day SAE occurred in seven patients (2.5%) and no recorded deaths. The CSRS performed with a sensitivity of 71.4% (95% confidence interval [CI] 30.3–94.9%), specificity 72.8% (95% CI 67.1–77.9%) for a threshold score of 1 or higher. Conclusion: Syncope patients in our study were predominantly very low to low risk (72%). The prevalence of 30‐day SAE was low, majority occurring following hospital discharge. Sensitivity estimates for CSRS was lower than the derivation study but lacked robustness with wide CIs because of a small sample size and number of events observed. However, the CSRS did not miss any clinically relevant outcomes in low risk patients making it potentially useful in aiding their disposition. Larger validation studies in Australia are encouraged to further test the diagnostic accuracy of the CSRS. [ABSTRACT FROM AUTHOR]

Objectives: Nursing staff in residential aged care facilities (RACF)s often make decisions about the transfer of residents to the emergency department (ED). This paper describes the protocol of a study that aims to understand decision‐making process utilised by RACF registered nurses (RNs) and to explore the perceptions of RNs about the decision and communication process between RACF and ED. Methods: The proposed mixed‐method study will survey and interview RACF RNs to understand their decision to transfer a resident and collect information about older people referred to the ED. Data collection will involve telephone survey, ED information system (EDIS) data and semistructured interviews. Results: The project outcomes will provide an understanding of existing ED service provision, communication between facilities and the reasons for transfer of older person to ED. This may inform redesign in communication processes between the ED and local RACFs and outreach care from the ED to RACFs. [ABSTRACT FROM AUTHOR]

Objectives: Expiratory radiographs are sometimes performed in addition to inspiratory radiographs when a diagnosis of pneumothorax is suspected. There is little published evidence to support this practice and most studies suggest the additional radiograph does not confer any benefit in terms of increased sensitivity. The present study is the first to assess if specialist emergency physicians are more likely to detect a pneumothorax on an inspiratory radiograph compared to an expiratory radiograph. Methods: Across two urban district EDs 103 paired radiographs positive for pneumothorax and 112 negative controls were identified for inclusion in the study. These were reviewed by three specialist emergency physicians who rated them as either positive or negative for pneumothorax. Results: The mean sensitivity for the three reviewers was 84.8% (95% CI 82.0–87.5) for the inspiratory radiographs and 91.9% (95% CI 88.2–95.6) for the expiratory radiographs, a mean absolute difference of 7.1% (95% CI 2.2–12.1, P = 0.025) in favour of expiratory radiographs. Conclusions: When reviewed by emergency physicians the present study found expiratory radiographs confer an increase in sensitivity for the diagnosis of pneumothorax compared with inspiratory radiographs. In certain patients where the clinical suspicion for pneumothorax is high performing an expiratory radiograph may increase the likelihood of the diagnosis being made in the ED. [ABSTRACT FROM AUTHOR]

Objective: ED access block is an ongoing significant problem and has been associated with excess mortality. Multiple models of care have been studied in an effort to improve access block and other key performance indicators (KPIs) of ED. Methods: This present study describes the impact of a new model of care using an ED led, consultant run clinical decision unit (CDU) on performance, using a retrospective analysis of data for 9 month periods before and after the introduction of the CDU model of care. Primary outcomes were access block (percentage of patients admitted >8 h), discharge National Emergency Access Target (NEAT) adherence and Queensland Ambulance Service level three escalations. Results: After the implementation of the CDU, access block significantly improved. There was a significant improvement in NEAT adherence. Total ambulance ramping time fell by 58% and ambulance service level three escalations fell from 21 to 5 post‐CDU implementation. Overall there was no change to hospital mortality numbers. The percentage of patients that did not wait and 30 day representations showed a small but statistically significant decrease. Conclusion: In summary, this ED led, consultant run CDU model of care resulted in significantly improved performance on a range of KPIs, including improvement in access block and NEAT figures. The substantial improvements in ambulance ramping and escalations also indicated that the department was able to cope better with periods of high activity. [ABSTRACT FROM AUTHOR]

Reliance on the hemodynamic response as a surrogate marker of neural activity imposes an intrinsic limit on the spatial specificity of functional MRI. An alternative approach based on diffusion-weighted functional MRI (DfMRI) has been reported as a contrast less reliant on hemodynamic effects, however current evidence suggests that both hemodynamic and unique neural sources contribute to the diffusion signal. Here we compare activation patterns obtained with the standard blood oxygenation level-dependent (BOLD) contrast to DfMRI in order to gain a deeper understanding of how the BOLD proportion contributes to the observable diffusion signal. Both individual and group-level activation patterns obtained with DfMRI and BOLD to a visual field stimulation paradigm were analyzed. At the individual level, the DfMRI contrast showed a strong, positive relationship between the volumes of cortex activated in response to quadrant- and hemi-field visual stimulation. This was not observed in the corresponding BOLD experiment. Overall, the DfMRI response indicated less between-subject variability, with random effects analyses demonstrating higher statistical values at the peak voxel for DfMRI. Furthermore, the spatial extent of the activation was more restricted to the primary visual region for DfMRI than BOLD. However, the diffusion signal was sensitive to the hemodynamic response in a manner dependent on experimental manipulation. It was also limited by its low signal-to-noise ratio (SNR), demonstrating lower sensitivity than BOLD. Together these findings both support DfMRI as a contrast that bears a closer spatial relationship to the underlying neural activity than BOLD, and raise important caveats regarding its utilization. Models explaining the DfMRI signal change need to consider the dynamic vascular contributions that may vary with neural activity. [ABSTRACT FROM AUTHOR]

This research explored the feasibility of using multidimensional scaling (MDS) analysis in novel combination with other techniques to study comprehension of epistemic adverbs expressing doubt and certainty (e.g., evidently, obviously, probably) as they relate to health communication in clinical settings. In Study 1, Australian English speakers performed a dissimilarity-rating task with sentence pairs containing the target stimuli, presented as "doctors' opinions." Ratings were analyzed using a combination of cultural consensus analysis (factor analysis across participants), weighted-data classical-MDS, and cluster analysis. Analyses revealed strong within-community consistency for a 3-dimensional semantic space solution that took into account individual differences, strong statistical acceptability of the MDS results in terms of stress and explained variance, and semantic configurations that were interpretable in terms of linguistic analyses of the target adverbs. The results confirmed the feasibility of using MDS in this context. Study 2 replicated the results with Canadian English speakers on the same task. Semantic analyses and stress decomposition analysis were performed on the Australian and Canadian data sets, revealing similarities and differences between the two groups. Overall, the results support using MDS to study comprehension of words critical for health communication, including in future studies, for example, second language speaking patients and/or practitioners. More broadly, the results indicate that the techniques described should be promising for comprehension studies in many communicative domains, in both clinical settings and beyond, and including those targeting other aspects of language and focusing on comparisons across different speech communities. [ABSTRACT FROM AUTHOR]

Background: Miscommunication in the healthcare sector can be life-threatening. The rising number of migrant patients and foreign-trained staff means that communication errors between a healthcare practitioner and patient when one or both are speaking a second language are increasingly likely. However, there is limited research that addresses this issue systematically. This protocol outlines a hospital-based study examining interactions between healthcare practitioners and their patients who either share or do not share a first language. Of particular interest are the nature and efficacy of communication in language-discordant conversations, and the degree to which risk is communicated. Our aim is to understand language barriers and miscommunication that may occur in healthcare settings between patients and healthcare practitioners, especially where at least one of the speakers is using a second (weaker) language. Methods/Design: Eighty individual interactions between patients and practitioners who speak either English or Chinese (Mandarin or Cantonese) as their first language will be video recorded in a range of in- and out-patient departments at three hospitals in the Metro South area of Brisbane, Australia. All participants will complete a language background questionnaire. Patients will also complete a short survey rating the effectiveness of the interaction. Recordings will be transcribed and submitted to both quantitative and qualitative analyses to determine elements of the language used that might be particularly problematic and the extent to which language concordance and discordance impacts on the quality of the patient-practitioner consultation. Discussion: Understanding the role that language plays in creating barriers to healthcare is critical for healthcare systems that are experiencing an increasing range of culturally and linguistically diverse populations both amongst patients and practitioners. The data resulting from this study will inform policy and practical solutions for communication training, provide an agenda for future research, and extend theory in health communication. [ABSTRACT FROM AUTHOR]

Lateralization of temporal lobe epilepsy (TLE) is critical for successful outcome of surgery to relieve seizures. TLE affects brain regions beyond the temporal lobes and has been associated with aberrant brain networks, based on evidence from functional magnetic resonance imaging. We present here a machine learning-based method for determining the laterality of TLE, using features extracted from resting-state functional connectivity of the brain. A comprehensive feature space was constructed to include network properties within local brain regions, between brain regions, and across the whole network. Feature selection was performed based on random forest and a support vector machine was employed to train a linear model to predict the laterality of TLE on unseen patients. A leaveone- patient-out cross validation was carried out on 12 patients and a prediction accuracy of 83% was achieved. The importance of selected features was analyzed to demonstrate the contribution of resting-state connectivity attributes at voxel, region, and network levels to TLE lateralization. [ABSTRACT FROM AUTHOR]

Background: Seizures and interictal spikes in mesial temporal lobe epilepsy (MTLE)affect a network of brain regions rather than a single epileptic focus. Simultaneous electroencephalography and functional magnetic resonance imaging (EEG-fMRI) studies have demonstrated a functional network in which hemodynamic changes are time-locked to spikes. However, whether this reflects the propagation of neuronal activity from a focus,or conversely the activation of a network linked to spike generation remains unknown. The functional connectivity (FC) changes prior to spikes may provide information about the connectivity changes that lead to the generation of spikes. We used EEG-fMRI to investigate FC changes immediately prior to the appearance of interictal spikes on EEG in patients with MTLE. Methods/principal findings: Fifteen patients with MTLE underwent continuous EEG-fMRI during rest. Spikes were identified on EEG and three 10 s epochs were defined relative to spike onset: spike (0-10 s), pre-spike (-10 to 0 s), and rest (-20 to -10 s, with no previous spikes in the preceding 45s). Significant spike-related activation in the hippocampusipsilateral to the seizure focus was found compared to the pre-spike and rest epochs. The peak voxel within the hippocampus ipsilateral to the seizure focus was used as a seed region for FC analysis in the three conditions. A significant change in FC patterns was observed before the appearance of electrographic spikes. Specifically, there was significant loss of coherence between both hippocampi during the pre-spike period compared to spike and rest states. Conclusion/significance: In keeping with previous findings of abnormal inter-hemispheric hippocampal connectivity in MTLE, our findings specifically link reduced connectivity to the period immediately before spikes. This brief decoupling is consistent with a deficit in mutual(inter-hemispheric) hippocampal inhibition that may predispose to spike generation. [ABSTRACT FROM AUTHOR]

In this paper we provide normative data along multiple cognitive and affective variable dimensions for a set of 110 sounds, including living and manmade stimuli. Environmental sounds are being increasingly utilized as stimuli in the cognitive, neuropsychological and neuroimaging fields, yet there is no comprehensive set of normative information for these type of stimuli available for use across these experimental domains. Experiment 1 collected data from 162 participants in an on-line questionnaire, which included measures of identification and categorization as well as cognitive and affective variables. A subsequent experiment collected response times to these sounds. Sounds were normalized to the same length (1 second) in order to maximize usage across multiple paradigms and experimental fields. These sounds can be freely downloaded for use, and all response data have also been made available in order that researchers can choose one or many of the cognitive and affective dimensions along which they would like to control their stimuli. Our hope is that the availability of such information will assist researchers in the fields of cognitive and clinical psychology and the neuroimaging community in choosing well-controlled environmental sound stimuli, and allow comparison across multiple studies. [ABSTRACT FROM AUTHOR]

Background: Syncope is a common problem but can have any of a broad range of underlying causes. Initial evaluation of the patient in the emergency department often does not identify a specific cause, and the cornerstone of management is reliable risk stratification with clinical decision rules.Objectives: The primary objective is to validate the utility and safety of the Canadian Syncope Risk Score (CSRS) as a clinical decision rule when assessing patients who present with syncope to Australian emergency departments. Our secondary objective is to evaluate the economic benefits of diverting patients with syncope at low risk of serious adverse events from admission to hospital.Methods and Analysis: Prospective, observational study. Patients aged 18 years or more who present to the emergency department (ED) after syncope in the preceding 24 hours and have returned to their baseline state will be enrolled. Patients will be contacted by telephone to determine whether they have experienced any adverse events within 30 days of their initial presentation to the ED. The CSRS will be applied retrospectively to determine the relationship between whether patients were admitted to hospital or discharged home and the reporting of serious adverse events for each CSRS risk level. We will also undertake a cost-effectiveness analysis from the health care perspective.Ethics Approval: Prince Charles Hospital Human Research Ethics Committee (reference, HREC/17/QPCH/48).Dissemination Of Results: Outcomes will be disseminated by Queensland Health and the funding body via social media, presented at local and national emergency medicine conferences, and published in international emergency medicine and health economics journals.Clinical Trials Registration: Not applicable. [ABSTRACT FROM AUTHOR]

Introduction: Decreased water displacement following increased neural activity has been observed using diffusion-weighted functional MRI (DfMRI) at high b-values. The physiological mechanisms underlying the diffusion signal change may be unique from the standard blood oxygenation level-dependent (BOLD) contrast and closer to the source of neural activity. Whether DfMRI reflects neural activity more directly than BOLD outside the primary cerebral regions remains unclear., Methods: Colored and achromatic Mondrian visual stimuli were statistically contrasted to functionally localize the human color center Area V4 in neurologically intact adults. Spatial and temporal properties of DfMRI and BOLD activation were examined across regions of the visual cortex., Results: At the individual level, DfMRI activation patterns showed greater spatial specificity to V4 than BOLD. The BOLD activation patterns were more prominent in the primary visual cortex than DfMRI, where activation was localized to the ventral temporal lobe. Temporally, the diffusion signal change in V4 and V1 both preceded the corresponding hemodynamic response, however the early diffusion signal change was more evident in V1., Conclusions: DfMRI may be of use in imaging applications implementing cognitive subtraction paradigms, and where highly precise individual functional localization is required.

Lateralization of temporal lobe epilepsy (TLE) is critical for successful outcome of surgery to relieve seizures. TLE affects brain regions beyond the temporal lobes and has been associated with aberrant brain networks, based on evidence from functional magnetic resonance imaging. We present here a machine learning-based method for determining the laterality of TLE, using features extracted from resting-state functional connectivity of the brain. A comprehensive feature space was constructed to include network properties within local brain regions, between brain regions, and across the whole network. Feature selection was performed based on random forest and a support vector machine was employed to train a linear model to predict the laterality of TLE on unseen patients. A leave-one-patient-out cross validation was carried out on 12 patients and a prediction accuracy of 83% was achieved. The importance of selected features was analyzed to demonstrate the contribution of resting-state connectivity attributes at voxel, region, and network levels to TLE lateralization.