The vestigial pinna-orienting system in humans briefly suppresses superior auricular muscle activity during reflexive orienting toward auditory stimuli.

The vestigial pinna-orienting system in humans is capable of increasing the activity of several auricular muscles in response to lateralized transient auditory stimuli. For example, transient increases in electromyographic activity in the posterior auricular muscle (PAM) to an attention-capturing stimulus have been documented. For the current study, surface electromyograms (EMGs) were recorded from the PAMs and superior auricular muscles (SAMs) of 10 normal-hearing participants. During the experiments, lateralized transient auditory stimuli, such as a crying baby, a shattering vase, or the participant's first names, were presented. These transient stimuli were either presented in silence or when participants actively listened to a podcast. Although ipsilateral PAM activity increased in response to transient stimuli, the SAM displayed the opposite behavior, i.e., a brief, ipsilateral suppression of activity. This suppression of ipsilateral SAM activity was more frequent on the right (75%) than left side (35%), whereas an ipsilateral PAM increase was roughly equal in prevalence on the two sides (left: 90%, right: 95%). During the active listening task, SAM suppression on the right ear was significantly larger in response to ipsilateral stimuli, compared with contralateral ones (P = 0.002), whereas PAM activity increased significantly (P = 0.002). Overall, this study provides evidence of a systematic transient suppression of the SAM during exogenous attention. This could suggest a more complex system than previously assumed, as the presence of synchronized excitatory and inhibitory components in different auricular muscles points toward a coordinated attempt at reflexively orienting the pinna toward a sound.NEW & NOTEWORTHY This study provides evidence that two auricular muscles in humans, the posterior and superior auricular muscles (PAM, SAM), react fundamentally different to lateralized transient auditory stimuli, especially during active listening. Although the PAM reacts with a transient increase in ipsilateral activity, ongoing ipsilateral SAM activity is briefly suppressed at the same time. This indicates the presence of a more complex and nuanced pinna-orienting system, with synchronized excitatory and inhibitory components in humans, than previously suspected.

The role of attention in immersion: The two-competitor model.

Currently, we face an exponentially increasing interest in immersion, especially sensory-driven immersion, mainly due to the rapid development of ideas and business models centered around a digital virtual universe as well as the increasing availability of affordable immersive technologies for education, communication, and entertainment. However, a clear definition of 'immersion', in terms of established neurocognitive concepts and measurable properties, remains elusive, slowing research on the human side of immersive interfaces. To address this problem, we propose a conceptual, taxonomic model of attention in immersion. We argue (a) modeling immersion theoretically as well as studying immersion experimentally requires a detailed characterization of the role of attention in immersion, even though (b) attention, while necessary, cannot be a sufficient condition for defining immersion. Our broader goal is to characterize immersion in terms that will be compatible with established psychophysiolgical measures that could then in principle be used for the assessment and eventually the optimization of an immersive experience. We start from the perspective that immersion requires the projection of attention to an induced reality, and build on accepted taxonomies of different modes of attention for the development of our two-competitor model. The two-competitor model allows for a quantitative implementation and has an easy graphical interpretation. It helps to highlight the important link between different modes of attention and affect in studying immersion.

Prevalence and Risk Factors of Psychological Distress among Older People Seeking Health Care at Hospital in Dhaka City.

Increasing age is the main risk factor for chronic illnesses. The illnesses are not only physical, but also affect their psychological well-being and this has a significant effect on their quality of life. Numerous researches have shown that there is high prevalence of psychological distress in different medical and surgical patients while considerable percentage that is not detected by doctors. The study was conducted to identify the prevalence and risk factors of psychological distress in older people seeking health care at hospital in Dhaka city. This was a cross-sectional study conducted in the Bangladesh Association for the Aged and Institution of Geriatric Medicine (Bangladesh Probin Hospital) in Dhaka city, Bangladesh. A total of 451 older people seeking for healthcare was interviewed face-to-face using a standard Bengali validated General Health Care Questionnaire-12 (GHQ-12). Recruitment of respondents was based on the systematic random sampling of the older people aged at or more than 60 years who were seeking health care at hospital in Dhaka city. A total of 59.65% (n=269) participants were found to have psychological distress. Age of more than 75, education up to secondary level, being unemployment, living alone, respondents with lower socioeconomic background, not having spouse, history of bereavement was found to be significantly associated with psychological distress. Other factors such as smokers, respondents who consume alcohol, physically inactive older people, older people with multiple comorbidities and having diagnosed with a disease more than 6 months were found to be associated with psychological distress. Majority of the older patients with physical illness were distressed. The prevalence of psychological distress among older peoples seeking for healthcare with multiple comorbidities who seek care in the hospital was very high (59.65%). Age, education, marital status, history of bereavement, smoking, alcohol use, physical activity and presence of multiple comorbidities were independent determinants of psychological distress among older people seeking for healthcare. Encouraging healthy lifestyle through cessation of smoking and alcohol use and increasing physical activity could be an effective step in reducing psychological comorbidities among older people seeking for healthcare.

Complete Common Bile Duct Injury after Laparoscopic Cholecystectomy in Situs Inversus Totalis: A Case Report, Review of the Literature and Illustrative Case Video.

INTRODUCTION AND IMPORTANCE: Situs Inversus Totalis (SIT) is a rare condition characterized by the transposition of internal organs. Given the anatomical variations in SIT, surgeons must exercise extreme caution when performing laparoscopic cholecystectomy to avoid iatrogenic bile duct injury. Despite the high difficulty index associated with laparoscopic cholecystectomy in SIT, there is only one case report of common bile duct (CBD) injury in the English-language literature. CASE PRESENTATION: A 41-year-old female patient, known to have Kartagener syndrome, underwent laparoscopic cholecystectomy for acute cholecystitis and was discharged home on post-operative day one. However, on post-operative day five, the patient presented to the emergency room with abdominal pain, fever, and jaundice. Laboratory tests revealed leukocytosis and hyperbilirubinemia. Radiological images revealed complete occlusion of the CBD. A delayed approach was chosen, and six weeks after her initial operation, a hepaticojejunostomy was performed. CLINICAL DISCUSSION: Laparoscopic cholecystectomy is the standard operative procedure for gallbladder disease. The unique anatomy of SIT increases the risk of CBD injury during laparoscopic cholecystectomy. Surgeons are required to perform a mirror-image procedure and adhere to the basic principles of safe laparoscopic cholecystectomy in SIT. This is only the second reported case of CBD injury in SIT patients. CONCLUSION: Laparoscopic cholecystectomy in SIT presents a significant challenge. In patients with SIT, preventing CBD injury is the best approach, and referral to an experienced hepato-pancreato-biliary (HPB) surgeon is recommended. A delayed approach to CBD injuries in SIT allows thorough planning and understanding of the complex anatomical variations in these patients.

Zoonoses research in Somalia: A scoping review using a One Health approach.

Zoonoses are likely to cause a substantial burden on both human and animal health systems in Somalia, given the close proximity between the pastoralist majority and their livestock. However, decades of instability leading to weak disease surveillance have meant that data on the burden of zoonoses is lacking. The aim of this scoping review was to assess and synthesize the available literature on the presence and burden of zoonoses in Somalia. We used keywords to search Web of Science for relevant publications. Studies were included if they contained relevant data on a zoonosis and were undertaken in Somalia or were undertaken in another country where exposure could reasonably be assumed to have occurred in Somalia (e.g., migrants/refugees, returning soldiers, exported animals). Studies were not included if they focused on Somali ethnic communities permanently living elsewhere or if zoonotic aspects were not considered. We extracted data on disease(s) reported, geographic focus, data reported (human, animal, environment), study design and author affiliation. A total of 22 zoonotic infections were documented in 76 publications. The most frequently studied diseases were Rift Valley Fever (n = 15, 17%), brucellosis (n = 13, 14%) and hepatitis E (n = 10, 11%). Around 30% of papers reported data from relevant populations outside Somalia. Only 18 papers undertook laboratory analysis within Somalia. Most papers reported data on humans (45%) and animals (36%) with limited research on the environmental domain. Descriptive studies (47%) dominated and most were led by non-Somali researchers (89% in first authors and 95% of last authors). This study highlights the need for well-designed zoonoses research in Somalia supported by capacity building of local researchers and investments in diagnostic laboratories.

Prioritization of zoonoses for multisectoral, One Health collaboration in Somalia, 2023.

Background: The human population of Somalia is vulnerable to zoonoses due to a high reliance on animal husbandry. This disease risk is exacerbated by relatively low income (poverty) and weak state capacity for health service delivery in the country as well as climate extremes and geopolitical instability in the region. To address this threat to public health efficiently and effectively, it is essential that all sectors have a common understanding of the priority zoonotic diseases of greatest concern to the country. Methods: Representatives from human, animal (domestic and wildlife), agriculture, and environmental health sectors undertook a multisectoral prioritization exercise using the One Health Zoonotic Disease Prioritization (OHZDP) tool developed by the United States CDC. The process involved: reviewing available literature and creating a longlist of zoonotic diseases for potential inclusion; developing and weighting criteria for establishing the importance of each zoonoses; formulating categorical questions (indicators) for each criteria; scoring each disease according to the criteria; and finally ranking the diseases based on the final score. Participants then brainstormed and suggested strategic action plans to prevent, and control prioritized zoonotic diseases. Results: Thirty-three zoonoses were initially considered for prioritization. Final criteria for ranking included: 1) socioeconomic impact (including sensitivity) in Somalia; 2) burden of disease in humans in Somalia); 3) availability of intervention in Somalia; 4) environmental factors/determinants; and 5) burden of disease in animals in Somalia. Following scoring of each zoonotic disease against these criteria, and further discussion of the OHZDP tool outputs, seven priority zoonoses were identified for Somalia: Rift Valley fever, Middle East respiratory syndrome, anthrax, trypanosomiasis, brucellosis, zoonotic enteric parasites (including Giardia and Cryptosporidium), and zoonotic influenza viruses. Conclusions: The final list of seven priority zoonotic diseases will serve as a foundation for strengthening One Health approaches for disease prevention and control in Somalia. It will be used to: shape improved multisectoral linkages for integrated surveillance systems and laboratory networks for improved human, animal, and environmental health; establish multisectoral public health emergency preparedness and response plans using One Health approaches; and enhance workforce capacity to prevent, control and respond to priority zoonotic diseases.

Assessment of Vestigial Auriculomotor Activity to Acoustic Stimuli Using Electrodes In and Around the Ear.

Recently, it has been demonstrated that electromyographic (EMG) activity of auricular muscles in humans, especially the postauricular muscle (PAM), depends on the spatial location of auditory stimuli. This observation has only been shown using wet electrodes placed directly on auricular muscles. To move towards a more applied, out-of-the-laboratory setting, this study aims to investigate if similar results can be obtained using electrodes placed in custom-fitted earpieces. Furthermore, with the exception of the ground electrode, only dry-contact electrodes were used to record EMG signals, which require little to no skin preparation and can therefore be applied extremely fast. In two experiments, auditory stimuli were presented to ten participants from different spatial directions. In experiment 1, stimuli were rapid onset naturalistic stimuli presented in silence, and in experiment 2, the corresponding participant's first name, presented in a "cocktail party" environment. In both experiments, ipsilateral responses were significantly larger than contralateral responses. Furthermore, machine learning models objectively decoded the direction of stimuli significantly above chance level on a single trial basis (PAM: ≈ 80%, in-ear: ≈ 69%). There were no significant differences when participants repeated the experiments after several weeks. This study provides evidence that auricular muscle responses can be recorded reliably using an almost entirely dry-contact in-ear electrode system. The location of the PAM, and the fact that in-ear electrodes can record comparable signals, would make hearing aids interesting devices to record these auricular EMG signals and potentially utilize them as control signals in the future.

COVID-19 and its prevention in internally displaced person (IDP) camps in Somalia: impact on livelihood, food security and mental health.

BACKGROUND: Somalia has over 2.6 million internally displaced people (IDP) that depend on daily wages and humanitarian assistance for their livelihoods. This study investigated the impact of COVID-19 on livelihoods, food security and mental health of Somalia's IDPs. METHODS: A questionnaire was conducted with "breadwinners" (n = 585) residing in 15 randomly selected IDP camps. Mental health was assessed using the 5-item World Health Organization Wellbeing Index (WHO-5) and the Patient Health Questionnaire-9 (PHQ-9). Multivariable regression was used to explore the effect of depressive symptoms on soap use and ability to pay for food/medicine/rent. RESULTS: Knowledge of COVID-19 symptoms, transmission and prevention was relatively high, however only 55% reported using soap for hand washing. Around one third perceived that prohibition of public gatherings had negatively impacted weekly earnings. Participants reported difficulty buying food (85%), medicine (82%) and paying rent (51%) because of COVID-19. The majority were assessed as having low wellbeing and high depressive symptoms (mean WHO-5 = 44.2/100; mean PHQ-9 = 18.6/27), with most (74%) indicating that they felt worse than before the pandemic. Compared to people with low depressive symptoms, people with high depressive symptoms were less likely to use soap (aOR = 0.3, 95% CI = 0.2, 0.7; P < 0.001) and more likely to report difficulty buying food (aOR = 2.2; 95% CI = 1.1, 4.3; P = 0.02). CONCLUSION: COVID-19 and associated restrictions have negatively impacted Somalia's internally displaced population. Livelihood and mental health support is urgently needed in the recovery phase of the pandemic and should be factored into future pandemic planning.

Speech Tracking in Complex Auditory Scenes with Differentiated In- and Out-Field-Of-View Processing in Hearing Aids.

In naturalistic auditory scenes, relevant information is rarely concentrated at a single location, but rather unpredictably scattered in- and out-field-of-view (in-/out-FOV). Although the parsing of a complex auditory scene is a fairly simple job for a healthy human auditory system, the uncertainty represents a major issue in the development of effective hearing aid (HA) processing strategies. Whereas traditional omnidirectional microphones (OM) amplify the complete auditory scene without enhancing signal-to-noise-ratio (SNR) between in- and out-FOV streams, directional microphones (DM) may greatly increase SNR at the cost of preventing HA users to perceive out-FOV information. The present study compares the conventional OM and DM HA settings to a split processing (SP) scheme differentiating between in- and out-FOV processing. We recorded electroencephalographic data of ten young, normal-hearing listeners who solved a cocktail-party-scenario-paradigm with continuous auditory streams and analyzed neural tracking of speech with a stimulus reconstruction (SR) approach. While results for all settings exhibited significantly higher SR accuracies for attended in-FOV than unattended out-FOV streams, there were distinct differences between settings. In-FOV SR performance was dominated by DM and SP and out-FOV SR accuracies were significantly higher for SP compared to OM and DM. Our results demonstrate the potential of a SP approach to combine the advantages of traditional OM and DM settings without introduction of significant compromises.

Clinical Characteristics and Prognosis of Young Middle Eastern Adults with ST-Elevation Myocardial Infarction: One-Year Follow-Up.

AIMS: Few studies have investigated premature ST-elevation myocardial infarction (STEMI) in the Middle East. We aimed to compare the clinical characteristics and one-year prognosis of young (<45 years) and older (≥45 years) Middle Eastern adults with STEMI. METHODS AND MATERIAL: A total of 706 patients with STEMI, who were prospectively enrolled in the First Jordanian Percutaneous Coronary Intervention Registry, were stratified into two groups (<45 or ≥45 years). Baseline clinical variables and one-year major adverse cardiovascular events (MACE) were evaluated. RESULTS: Young patients (<45 years) comprised 17.4% of STEMI patients (123 of 706). Compared with older patients (≥45 years), young patients were mostly male (96% vs 82%, P<0.001), smokers (86% vs 49%, P<0.001) and less likely to have multi-vessel disease (26% vs 44%, P=0.001). Anterior STEMI was the most common diagnosis and left anterior descending artery was the most common culprit vessel in both groups. There were no significant differences between the younger and older patients in in-hospital (20% vs 19%, P=0.12) and one-year MACE (24% vs 26%, P=0.68). However, none (0%) of the young died during one-year follow-up while 21 (4%) of the older patients died (P=0.036). CONCLUSIONS: Young adult patients in the Middle East with STEMI are more likely to be smoking men with multiple risk factors and single vessel disease by angiography. Although, younger patients had similar one-year MACE to older patients, their mortality rate appears to be better. A larger study is warranted to investigate this vulnerable group of patients to prevent future events.

A Novel Benzopyrane Derivative Targeting Cancer Cell Metabolic and Survival Pathways.

(1) Background: Today, the discovery of novel anticancer agents with multitarget effects and high safety margins represents a high challenge. Drug discovery efforts indicated that benzopyrane scaffolds possess a wide range of pharmacological activities. This spurs on building a skeletally diverse library of benzopyranes to identify an anticancer lead drug candidate. Here, we aim to characterize the anticancer effect of a novel benzopyrane derivative, aiming to develop a promising clinical anticancer candidate. (2) Methods: The anticancer effect of SIMR1281 against a panel of cancer cell lines was tested. In vitro assays were performed to determine the effect of SIMR1281 on GSHR, TrxR, mitochondrial metabolism, DNA damage, cell cycle progression, and the induction of apoptosis. Additionally, SIMR1281 was evaluated in vivo for its safety and in a xenograft mice model. (3) Results: SIMR1281 strongly inhibits GSHR while it moderately inhibits TrxR and modulates the mitochondrial metabolism. SIMR1281 inhibits the cell proliferation of various cancers. The antiproliferative activity of SIMR1281 was mediated through the induction of DNA damage, perturbations in the cell cycle, and the inactivation of Ras/ERK and PI3K/Akt pathways. Furthermore, SIMR1281 induced apoptosis and attenuated cell survival machinery. In addition, SIMR1281 reduced the tumor volume in a xenograft model while maintaining a high in vivo safety profile at a high dose. (4) Conclusions: Our findings demonstrate the anticancer multitarget effect of SIMR1281, including the dual inhibition of glutathione and thioredoxin reductases. These findings support the development of SIMR1281 in preclinical and clinical settings, as it represents a potential lead compound for the treatment of cancer.

Speech induced binaural beats: Electrophysiological assessment of binaural interaction.

This paper introduces and evaluates a speech signal manipulation scheme that generates transient speech induced binaural beats (SBBs). These SBBs can only be perceived when different signals are presented dichotically (to both ears). Event-related potentials were recorded in 22 normal-hearing subjects. Dichotic stimulus presentation reliably evoked auditory late responses (ALRs) in all subjects using such manipulated signals. As control measurements, diotic stimulation modalities were presented to confirm that the ALRs were not evoked by the speech signal itself or that the signal manipulation scheme created audible artifacts. Since diotic measurements evoked no ALRs, responses from dichotic stimulation are a pure correlate of binaural interaction. While there are several auditory stimuli (mostly modulated sinusoids or noise) that share this characteristic, none of them are based on running speech. Because SBBs can be added to any arbitrary speech signal, they could easily be combined with psychoacoustic tests, for example speech reception thresholds, adding an objective measure of binaural interaction.

Vestigial auriculomotor activity indicates the direction of auditory attention in humans.

Unlike dogs and cats, people do not point their ears as they focus attention on novel, salient, or task-relevant stimuli. Our species may nevertheless have retained a vestigial pinna-orienting system that has persisted as a 'neural fossil' within in the brain for about 25 million years. Consistent with this hypothesis, we demonstrate that the direction of auditory attention is reflected in sustained electrical activity of muscles within the vestigial auriculomotor system. Surface electromyograms (EMGs) were taken from muscles that either move the pinna or alter its shape. To assess reflexive, stimulus-driven attention we presented novel sounds from speakers at four different lateral locations while the participants silently read a boring text in front of them. To test voluntary, goal-directed attention we instructed participants to listen to a short story coming from one of these speakers, while ignoring a competing story from the corresponding speaker on the opposite side. In both experiments, EMG recordings showed larger activity at the ear on the side of the attended stimulus, but with slightly different patterns. Upward movement (perking) differed according to the lateral focus of attention only during voluntary orienting; rearward folding of the pinna's upper-lateral edge exhibited such differences only during reflexive orienting. The existence of a pinna-orienting system in humans, one that is experimentally accessible, offers opportunities for basic as well as applied science.

Dogs, cats, monkeys and other animals perk their ears in the direction of sounds they are interested in. Humans and their closest ape relatives, however, appear to have lost this ability. Some humans are able to wiggle their ears, suggesting that some of the brain circuits and muscles that allow automatic ear movements towards sounds are still present. This may be a 'vestigial feature', an ability that is maintained even though it no longer serves its original purpose. Now, Strauss et al. show that vestigial movements of muscles around the ear indicate the direction of sounds a person is paying attention to. In the experiments, human volunteers tried to read a boring text while surprising sounds like a traffic jam, a baby crying, or footsteps played. During this exercise, Strauss et al. recorded the electrical activity in the muscles of their ears to see if they moved in response to the direction the sound came from. In a second set of experiments, the same electrical recordings were made as participants listened to a podcast while a second podcast was playing from a different direction. The individuals' ears were also recorded using high resolution video. Both sets of experiments revealed tiny involuntary movements in muscles surrounding the ear closest to the direction of a sound the person is listening to. When the participants tried to listen to one podcast and tune out another, they also made ear 'perking' movements in the direction of their preferred podcast. The results suggest that movements of the vestigial muscles in the human ear indicate the direction of sounds a person is paying attention to. These tiny movements could be used to develop better hearing aids that sense the electrical activity in the ear muscles and amplify sounds the person is trying to focus on, while minimizing other sounds.

Hypertension in School Children of Dhaka City and Associated Risk Factors.

Hypertension has its origin in childhood but goes undetected unless specially looked for detection of hypertension in children will increase the awareness and lead to preventive strategies. The objective of the study was to determine the prevalence of hypertension in school children. This cross sectional study was conducted among children aged 10 to 17 years in three secondary level schools of Dhaka city, Bangladesh. This study included 1146 participants (both boys and girls) by systematic random sampling. Blood pressure was measured and plotted in Blood pressure (BP) chart to define hypertension and structured questionnaire were used to collect socio demographic information. The prevalence of hypertension in school children was 1.8% (male was 1.68% and female was 1.99%). It was noted that there was a strong correlation between body weight and BMI of the children with hypertension. A significant portion of the respondents had family history of hypertension, diabetes and obesity. There was also a positive relation between hypertension and food habit that include low vegetables and more fast food. It was concluded that hypertension exists among secondary level school children in Dhaka, Bangladesh and it is related with obesity, increased BMI, family history and dietary habit.

Implementation and Long-Term Evaluation of a Hearing Aid Supported Tinnitus Treatment Using Notched Environmental Sounds.

Recent work has shown that sharp spectral edges in acoustic stimuli might have advantageous effects in the treatment of tonal tinnitus. In the course of this paper, we evaluate the long-term effects of spectrally notched hearing aids on the subjective tinnitus distress. By merging recent experimental work with a computational tinnitus model, we modified the commercially available behind-the-ear hearing aids so that a frequency band of 0.5 octaves, centered on the patient's individual tinnitus frequency, was blocked out. Those hearing aids employ a steep notch filter that filters environmental sounds to suppress the tinnitus-related changes in neural firing by lateral inhibition. The computational model reveals a renormalization of pathologically increased neural response reliability and synchrony in response to spectrally modified input. The target group, fitted with spectrally notched hearing aids, was matched with a comparable control group, fitted with standard hearing aids of the same type but without a notch filter. We analyze the subjective self-assessment by tinnitus questionnaires, and we monitor the objective distress correlates in auditory evoked response phase data. Both, subjective and objective results show a noticeable trend of a larger therapeutic benefit for notched hearing correction.

Bilateral spontaneous pneumothoraces in anaplastic thyroid cancer.

Spontaneous pneumothorax is rarely associated with cancer. We describe a 73 year old man who presented with recurrent tumor in the right neck, mediastinal lymphadenopathy and bilateral pulmonary nodules after thyroidectomy. He was treated with lenvatinib and presented with bilateral pneumothoraces. Anaplastic thyroid cancer is an aggressive subtype of thyroid cancer that has limited response to cytotoxic chemotherapy and poor prognosis. Recent reports show that targeted therapy with a multiple receptor tyrosine kinase inhibitor, lenvatinib, may have improvement in progression-free survival, but rarely pneumothorax has been reported in those with lung metastases. Various mechanisms have been postulated, but necrosis of pulmonary lesions and/or subpleural micrometastases leading to bilateral pleural defects likely resulted in the development of pneumothoraces for our patient.

Reducing the Effect of Spurious Phase Variations in Neural Oscillatory Signals.

The phase-reset model of oscillatory EEG activity has received a lot of attention in the last decades for decoding different cognitive processes. Based on this model, the ERPs are assumed to be generated as a result of phase reorganization in ongoing EEG. Alignment of the phase of neuronal activities can be observed within or between different assemblies of neurons across the brain. Phase synchronization has been used to explore and understand perception, attentional binding and considering it in the domain of neuronal correlates of consciousness. The importance of the topic and its vast exploration in different domains of the neuroscience presses the need for appropriate tools and methods for measuring the level of phase synchronization of neuronal activities. Measuring the level of instantaneous phase (IP) synchronization has been used extensively in numerous studies of ERPs as well as oscillatory activity for a better understanding of the underlying cognitive binding with regard to different set of stimulations such as auditory and visual. However, the reliability of results can be challenged as a result of noise artifact in IP. Phase distortion due to environmental noise artifacts as well as different pre-processing steps on signals can lead to generation of artificial phase jumps. One of such effects presented recently is the effect of low envelope on the IP of signal. It has been shown that as the instantaneous envelope of the analytic signal approaches zero, the variations in the phase increase, effectively leading to abrupt transitions in the phase. These abrupt transitions can distort the phase synchronization results as they are not related to any neurophysiological effect. These transitions are called spurious phase variation. In this study, we present a model to remove generated artificial phase variations due to the effect of low envelope. The proposed method is based on a simplified form of a Kalman smoother, that is able to model the IP behavior in narrow-bandpassed oscillatory signals. In this work we first explain the details of the proposed Kalman smoother for modeling the dynamics of the phase variations in narrow-bandpassed signals and then evaluate it on a set of synthetic signals. Finally, we apply the model on ongoing-EEG signals to assess the removal of spurious phase variations.

Extensive septic myonecrosis related to compartment syndrome: is the upper extremity salvage achievable in precarious setting?

Management of acute compartment syndrome is well known and based on emergent and generous fasciotomies. In absence of such fasciotomies, or if they are performed too late, the compartment syndrome leads to a Volkmann's syndrome or to a dramatic septic myonecrosis raising the question of an amputation. However, salvage treatment of these extreme clinical presentations may be preferable at the upper extremity, particularly in developing countries where access to sophisticated prosthetic devices is limited. The authors report four typical observations about management of upper extremity delayed compartment syndromes with severe infectious complications. To clarify treatment principles and pitfalls, two situations are distinguished: subacute septic myonecrosis and chronic osteomyelitis. Management specificities of both situations are discussed according to literature data and available resources in austere environments. Despite challenging in low-resources setting, upper extremity salvage is possible at the cost of simple but iterative surgical procedures. Limitations are represented by the need of repeated blood transfusions in the subacute phase, and difficulties in providing medical treatment of bone infection in the chronic phase.

Free-field evoked auditory brainstem responses in cochlear implant users.

The importance of binaural cues in auditory stream formation and sound source segregation is widely accepted. When treating one ear with a cochlear implant (CI) the peripheral auditory system gets partially replaced and processing delays get added potentially, thus important interaural time differences get altered. However, these effects are not fully understood, leaving a lack of systematic binaural fitting strategies with respect to an optimal binaural fusion. To get new insights into such alterations, we suggest a novel method of free-field auditory brainstem evoked responses (ABRs) analysis in CI users. This method does not bypass the technically induced intrinsic delays of the sound processor while leaving the whole electrode array active, thus the most natural way of stimulation is provided. We compared the ABRs collected of 12 CI users and 12 normal hearing listeners using two different stimuli (chirp, click) at four different intensities each. We analyzed the ABRs using the average of 2000 trials as well as a single trial analysis and found consistent results in the ABRs' amplitudes and latencies, as well as in single trial relationships between both groups. This method provides a new perspective into the natural CI users' ABRs and can be useful in future research regarding binaural interaction and fusion.

Neurodynamic evaluation of hearing aid features using EEG correlates of listening effort.

In this study, we propose a novel estimate of listening effort using electroencephalographic data. This method is a translation of our past findings, gained from the evoked electroencephalographic activity, to the oscillatory EEG activity. To test this technique, electroencephalographic data from experienced hearing aid users with moderate hearing loss were recorded, wearing hearing aids. The investigated hearing aid settings were: a directional microphone combined with a noise reduction algorithm in a medium and a strong setting, the noise reduction setting turned off, and a setting using omnidirectional microphones without any noise reduction. The results suggest that the electroencephalographic estimate of listening effort seems to be a useful tool to map the exerted effort of the participants. In addition, the results indicate that a directional processing mode can reduce the listening effort in multitalker listening situations.