Acute transitory head mislocalization - a novel syndrome of pathological embodiment in a patient with traumatic brain injury - a case study.

Feeling of body ownership is a complex process with different brain mechanisms involved in integrating the varied and multiple representations of the body . The ability to discriminate between one's own and others' body parts can be lost after brain damage. We report a unique case study of a patient with head injury who experienced a phenomenon where he felt that his head was positioned with another person standing next to him. We describe this as a form of pathological embodiment and call it the "head mislocalization" phenomenon. We report his clinical findings and using the methods of lesion mapping and lesion network mapping postulate the neural mechanisms for this symptom.

Robustness of the emergence of synchronized clusters in branching hierarchical systems under parametric noise.

The dynamical robustness of networks in the presence of noise is of utmost fundamental and applied interest. In this work, we explore the effect of parametric noise on the emergence of synchronized clusters in diffusively coupled Chaté-Manneville maps on a branching hierarchical structure. We consider both quenched and dynamically varying parametric noise. We find that the transition to a synchronized fixed point on the maximal cluster is robust in the presence of both types of noise. We see that the small sub-maximal clusters of the system, which coexist with the maximal cluster, exhibit a power-law cluster size distribution. This power-law scaling of synchronized cluster sizes is robust against noise in a broad range of coupling strengths. However, interestingly, we find a window of coupling strength where the system displays markedly different sensitivities to noise for the maximal cluster and the small clusters, with the scaling exponent for the cluster distribution for small clusters exhibiting clear dependence on noise strength, while the cluster size of the maximal cluster of the system displays no significant change in the presence of noise. Our results have implications for the observability of synchronized cluster distributions in real-world hierarchical networks, such as neural networks, power grids, and communication networks, that necessarily have parametric fluctuations.

Self-motion induced environmental kinetopsia and pop-out illusion - Insight from a single case phenomenology.

Stable visual perception, while we are moving, depends on complex interactions between multiple brain regions. We report a patient with damage to the right occipital and temporal lobes who presented with a visual disturbance of inward movement of roadside buildings towards the centre of his visual field, that occurred only when he moved forward on his motorbike. We describe this phenomenon as "self-motion induced environmental kinetopsia". Additionally, he was identified to have another illusion, in which objects displayed on the screen, appeared to pop out of the background. Here, we describe the clinical phenomena and the behavioural tasks specifically designed to document and measure this altered visual experience. Using the methods of lesion mapping and lesion network mapping we were able to demonstrate disrupted functional connectivity in the areas that process flow-parsing such as V3A and V6 that may underpin self-motion induced environmental kinetopsia. Moreover, we suggest that altered connectivity to the regions that process environmental frames of reference such as retrosplenial cortex (RSC) might explain the pop-out illusion. Our case adds novel and convergent lesion-based evidence to the role of these brain regions in visual processing.

Impact of coupling on neuronal extreme events: Mitigation and enhancement.

We focus on the emergence of extreme events in a collection of aperiodic neuronal maps, under local diffusive coupling, as well as global mean-field coupling. Our central finding is that local diffusive coupling enhances the probability of occurrence of both temporal and spatial extreme events, while in marked contrast, global mean-field coupling suppresses extreme events. So the nature of the coupling crucially determines whether the extreme events are enhanced or mitigated by coupling. Further, in globally coupled systems, there exist initial states in a window of coupling strength that exhibit spatial extreme events, but not temporal extreme events, suggesting that spatial extreme events do not imply temporal extreme events. We also explored the existence of discernible patterns in the return maps of successive inter-event intervals in order to gauge short-term risk-assessment. We find that single neuronal maps, as well as systems under strong diffusive coupling, display broad noisy patterns in these return maps, with clusters around characteristic intervals, allowing some short-term predictability in the extreme event sequence. In contrast, under weak diffusive coupling and global coupling, inter-event intervals lose all perceptible correlations, and the distribution extends to very large inter-event intervals. Lastly, we investigated a non-local diffusive coupling form. Interestingly, this coupling yielded a large window where temporal extreme events occurred, but the spatial profile was synchronized, namely, we found synchronized temporal extreme events. Such synchronized extreme spiking is reminiscent of the neuronal activity leading to epileptic seizures and is of potential relevance to extreme events in brain activity.

Sensitivity and specificity of phrenic nerve electrophysiology to predict mechanical ventilation in the Guillain-Barré syndrome.

INTRODUCTION/AIMS: In Guillain-Barré syndrome (GBS), the sensitivity and specificity of phrenic compound muscle action potential (CMAP) measurements to predict endotracheal mechanical ventilation are unknown. Hence, we sought to estimate sensitivity and specificity. METHODS: We performed a 10-year retrospective analysis of adult GBS patients from our single-center laboratory database (2009 to 2019). The phrenic nerve amplitudes and latencies before ventilation were recorded along with other clinical and demographic features. Receiver operating curve (ROC) analysis with area under the curve (AUC) was used to determine the sensitivity and specificity with 95% confidence interval (CI) for phrenic amplitudes and latencies in predicting the need for mechanical ventilation. RESULTS: Two hundred five phrenic nerves were analyzed in 105 patients. The mean age was 46.1 ± 16.2 years, with 60% of them being male. Fourteen patients (13.3%) required mechanical ventilation. The average phrenic amplitudes were lower in the ventilated group (P = .003), but average latencies did not differ (P = .133). ROC analysis confirmed that phrenic amplitudes could predict respiratory failure (AUC = 0.76; 95% CI, 0.61 to 0.91; P < .002), but phrenic latencies could not (AUC = 0.60; 95% CI, 0.46 to 0.73; P = .256). The best threshold for amplitude was ≥0.6 mV, with sensitivity, specificity, and positive and negative predictive values of 85.7%, 58.2%, 24.0%, and 96.4%, respectively. DISCUSSION: Our study suggests that phrenic CMAP amplitudes can predict the need for mechanical ventilation in GBS. In contrast, phrenic CMAP latencies are not reliable. The high negative predictive value of phrenic CMAP amplitudes ≥0.6 mV can preclude mechanical ventilation, making these a useful adjunct to clinical decision-making.

The transition to synchronization on branching hierarchical lattices.

We study the transition to synchronization on hierarchical lattices using the evolution of Chaté-Manneville maps placed on a triangular lattice. Connections are generated between the levels of the triangular lattice, assuming that each site is connected to its neighbors on the level below with probability half. The maps are diffusively coupled, and the map parameters increase hierarchically, depending on the map parameters at the sites they are coupled to in the previous level. The system shows a transition to synchronization, which is second order in nature, with associated critical exponents. However, the V-lattice, which is a special realization of this lattice, shows a transition to synchronization that is discontinuous with accompanying hysteretic behavior. This transition can thus be said to belong to the class of explosive synchronization with the explosive nature depending on the nature of the substrate. We carry out finite-size-finite-time scaling for the continuous transition and analyze the scaling of the jump size for the discontinuous case. We discuss the implications of our results and draw parallels with avalanche statistics on branching hierarchical lattices.

Role of Pain-Related Evoked Potential in the Diagnosis of Meralgia Paresthetica.

INTRODUCTION: Entrapment of the lateral femoral cutaneous nerve (LFCN) of thigh results in meralgia paresthetica (MP). Standard electrophysiological tests for MP are technically demanding and unreliable. We aimed to study the role of pain-related evoked potentials (PREP) in the diagnosis of MP. METHODS: Patients with MP and normal volunteers were included. PREP was recorded by stimulating the skin over the lateral thigh 20 cm below the anterior-superior iliac spine and recording from the cortex at Cz. RESULTS: A total of 28 subjects and 56 LFCNs were studied. 36 nerves had MP and 20 were normal. The mean PREP latency was 118 (8) ms among normal controls and 164 (10.8) ms in MP. The optimal cut-off point for the diagnosis of MP was 134 ms. Area under receiver operator characteristic curve was 0.97; sensitivity was 91.7% and specificity was 100%. CONCLUSION: PREP is reliable and easy to use electrophysiological test in establishing the diagnosis of MP.

Healthcare provider and service user perspectives on STI risk reduction interventions for young people and MSM in the UK.

OBJECTIVE: Behavioural interventions have been shown to reduce sexual behaviours associated with increased risk of sexually transmitted infections in young people (<25 years) and men who have sex with men (MSM) internationally, but evidence from England is limited. We aimed to explore service provider and user experiences and perspectives on behavioural interventions to reduce sexual behaviour risks, and the use of automated methods to triage individuals to these services. METHODS: We conducted a sequential mixed methods study with sexual health service providers and users in 2015/2016. Qualitative interviews with providers and service users (heterosexual young people and MSM) in London and Brighton allowed us to explore a range of experiences and expectations. A subsequent national web-survey of service providers measured the feasibility of delivery within existing resources and preferences for intervention attributes. RESULTS: We conducted 35 service user (15 heterosexual young people; 20 MSM) and 26 provider interviews and had 100 web-survey responses. We found considerable heterogeneity in prevention services offered. Service users and providers were broadly supportive of tailoring interventions offered, but service users raised concerns about automated, data-driven triage, particularly around equity and fairness of service delivery. Digital technologies, including social media or apps, were appealing to providers, being less resource intensive. However, one-to-one talking interventions remained popular with both service users and providers, being familiar, trustworthy and personal. Key tensions between desirability of interventions and availability of resources to deliver them were acknowledged/recognised by providers and users. CONCLUSION: Overall, behavioural interventions to reduce sexual behaviour risks were viewed favourably by service providers and users, with key considerations including: privacy, personalisation and convenience. However, introducing desirable targeted interventions within heterogeneous sexual health settings will require resources to adapt interventions and research to fully understand the barriers and facilitators to use within routine services.

Sexual risk reduction interventions for patients attending sexual health clinics: a mixed-methods feasibility study.

BACKGROUND: Sexually transmitted infections (STIs) continue to represent a major public health challenge. There is evidence that behavioural interventions to reduce risky sexual behaviours can reduce STI rates in patients attending sexual health (SH) services. However, it is not known if these interventions are effective when implemented at scale in SH settings in England. OBJECTIVES: The study (Santé) had two main objectives - (1) to develop and pilot a package of evidence-based sexual risk reduction interventions that can be delivered through SH services and (2) to assess the feasibility of conducting a randomised controlled trial (RCT) to determine effectiveness against usual care. DESIGN: The project was a multistage, mixed-methods study, with developmental and pilot RCT phases. Preparatory work included a systematic review, an analysis of national surveillance data, the development of a triage algorithm, and interviews and surveys with SH staff and patients to identify, select and adapt interventions. A pilot cluster RCT was planned for eight SH clinics; the intervention would be offered in four clinics, with qualitative and process evaluation to assess feasibility and acceptability. Four clinics acted as controls; in all clinics, participants would be consented to a 6-week follow-up STI screen. SETTING: SH clinics in England. PARTICIPANTS: Young people (aged 16-25 years), and men who have sex with men. INTERVENTION: A three-part intervention package - (1) a triage tool to score patients as being at high or low risk of STI using routine data, (2) a study-designed web page with tailored SH information for all patients, regardless of risk and (3) a brief one-to-one session based on motivational interviewing for high-risk patients. MAIN OUTCOME MEASURES: The three outcomes were (1) the acceptability of the intervention to patients and SH providers, (2) the feasibility of delivering the interventions within existing resources and (3) the feasibility of obtaining follow-up data on STI diagnoses (primary outcome in a full trial). RESULTS: We identified 33 relevant trials from the systematic review, including videos, peer support, digital and brief one-to-one sessions. Patients and SH providers showed preferences for one-to-one and digital interventions, and providers indicated that these intervention types could feasibly be implemented in their settings. There were no appropriate digital interventions that could be adapted in time for the pilot; therefore, we created a placeholder for the purposes of the pilot. The intervention package was piloted in two SH settings, rather than the planned four. Several barriers were found to intervention implementation, including a lack of trained staff time and clinic space. The intervention package was theoretically acceptable, but we observed poor engagement. We recruited patients from six clinics for the follow-up, rather than eight. The completion rate for follow-up was lower than anticipated (16% vs. 46%). LIMITATIONS: Fewer clinics were included in the pilot than planned, limiting the ability to make strong conclusions on the feasibility of the RCT. CONCLUSION: We were unable to conclude whether or not a definitive RCT would be feasible because of challenges in implementation of a pilot, but have laid the groundwork for future research in the area. TRIAL REGISTRATION: Current Controlled Trials ISRCTN16738765. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 12. See the NIHR Journals Library website for further project information.

Reducing sexually transmitted infections (STIs) is a public health priority. Those most likely to be diagnosed with a STI are young people (aged 16­25 years) and men who have sex with men. Studies in other countries have shown that interventions aimed at changing sexual behaviour (e.g. increasing condom use) can reduce the chance of getting new STIs in patients attending sexual health (SH) clinics. However, it is not clear if these interventions will work in English sexual health clinics, or if they could be implemented within existing resources. This study aimed to find out if effective interventions could be adapted to an English setting and tested this in a randomised trial. The scientific literature was searched for potential interventions and 33 trials were found. Effective methods included videos, digital web-based interventions, self-testing kits and talking sessions (e.g. counselling). Patients and providers were asked which interventions were acceptable and preferences for digital and one-to-one talking interventions were found. Providers suggested that these were feasible to deliver. Data routinely collected from patients (e.g. number of partners) were used to select patients at a higher risk of having a STI, a computerised risk score calculation was developed, and the highest risk group was directed to a one-to-one counselling intervention. There were no appropriate digital interventions available; therefore, a stand-in web page was created to signpost users to appropriate SH resources. This was offered to all patients. The intervention package was piloted in two SH settings rather than the planned four because of a lack of clinic staff time and space. It was planned to follow up a subset of patients from all eight clinics 6 weeks after their visit to collect information on STI diagnoses. Patients were recruited from six clinics, but only 16% of patients completed the survey and returned a sample. It was not possible to conclude definitively whether or not a randomised trial is feasible because of challenges in implementation and recruitment.

Designing a brief behaviour change intervention to reduce sexually transmitted infections: a discrete choice experiment.

To understand whether people attending sexual health (SH) clinics are willing to participate in a brief behavioural change intervention (BBCI) to reduce the likelihood of future sexually transmitted infections (STIs) and to understand their preferences for different service designs, we conducted a discrete choice experiment (DCE) with young heterosexual adults (aged 16-25 years), and men who have sex with men (MSM) aged 16 or above, attending SH clinics in England. Data from 368 participants showed that people particularly valued BBCIs that involved talking (OR 1.45; 95%CI 1.35, 1.57 compared with an 'email or text'-based BBCIs), preferably with a health care professional rather than a peer. Findings also showed that 26% of respondents preferred 'email/texts' to all other options; the remaining 14% preferred not to participate in any of the offered BBCIs. These results suggest that most people attending SH clinics in England are likely to participate in a BBCI if offered, but the type/format of the BBCI is likely to be the single important determinant of uptake rather than characteristics such as the length and the number of sessions. Moreover, participants generally favoured 'talking'-based options rather than digital alternatives, which are likely to require the most resources to implement.

Gender, Migration, and Exclusionary Citizenship Regimes: Conceptualizing Transnational Abandonment of Wives as a Form of Violence Against Women.

Based on life history narratives of 57 women in India and interviews with 21 practitioners, we document the neglect, abuse, and instrumental deprivation of women's rights through the process of transnational abandonment. While gendered local sociocultural milieus and economic norms contribute to these harms, they are crucially enabled and sustained by transnational formal-legal frameworks. Widening the explanatory lens for understanding domestic violence beyond the family and community, we argue that in a globalized world, (inter)state policies serve to construct these women as a subordinate category of citizens-"disposable women"-who can be abused and abandoned with impunity.