Facial expression and emotion. / Mimik und Emotion.

Human facial expressions are unique in their ability to express our emotions and communicate them to others. The mimic expression of basic emotions is very similar across different cultures and has also many features in common with other mammals. This suggests a common genetic origin of the association between facial expressions and emotion. However, recent studies also show cultural influences and differences. The recognition of emotions from facial expressions, as well as the process of expressing one's emotions facially, occurs within an extremely complex cerebral network. Due to the complexity of the cerebral processing system, there are a variety of neurological and psychiatric disorders that can significantly disrupt the coupling of facial expressions and emotions. Wearing masks also limits our ability to convey and recognize emotions through facial expressions. Through facial expressions, however, not only "real" emotions can be expressed, but also acted ones. Thus, facial expressions open up the possibility of faking socially desired expressions and also of consciously faking emotions. However, these pretenses are mostly imperfect and can be accompanied by short-term facial movements that indicate the emotions that are actually present (microexpressions). These microexpressions are of very short duration and often barely perceptible by humans, but they are the ideal application area for computer-aided analysis. This automatic identification of microexpressions has not only received scientific attention in recent years, but its use is also being tested in security-related areas. This article summarizes the current state of knowledge of facial expressions and emotions.

Experience-dependent structural plasticity in the adult brain: How the learning brain grows.

Volumetric magnetic resonance imaging studies have shown that intense learning can be associated with grey matter volume increases in the adult brain. The underlying mechanisms are poorly understood. Here we used monocular deprivation in rats to analyze the mechanisms underlying use-dependent grey matter increases. Optometry for quantification of visual acuity was combined with volumetric magnetic resonance imaging and microscopic techniques in longitudinal and cross-sectional studies. We found an increased spatial vision of the open eye which was associated with a transient increase in the volumes of the contralateral visual and lateral entorhinal cortex. In these brain areas dendrites of neurons elongated, and there was a strong increase in the number of spines, the targets of synapses, which was followed by spine maturation and partial pruning. Astrocytes displayed a transient pronounced swelling and underwent a reorganization of their processes. The use-dependent increase in grey matter corresponded predominantly to the swelling of the astrocytes. Experience-dependent increase in brain grey matter volume indicates a gain of structure plasticity with both synaptic and astrocyte remodeling.

Non-idiopathic peripheral facial palsy: prognostic factors for outcome.

OBJECTIVES: There is a lack of data on patients' and diagnostic factors for prognostication of complete recovery in patients with non-idiopathic peripheral facial palsy (FP). METHODS: Cohort register-based study of 264 patients with non-idiopathic peripheral FP and uniform diagnostics and standardized treatment in a university hospital from 2007 to 2017 (47% female, median age: 57 years). Clinical data, facial grading, electrodiagnostics, motor function tests, non-motor function tests, and onset of prednisolone therapy were assessed for their impact on the probability of complete recovery using univariable and multivariable statistics. RESULTS: The most frequent reason for a non-idiopathic peripheral FP was a reactivation of Varicella Zoster Virus (VZV; 36.4%). Traumatic origin had a higher proportion of complete FP (52.9%). Furthermore, in traumatic FP, the mean interval between onset and start of prednisolone therapy was longer than in other cases (5.6 ± 6.2 days). Patients with reactivation of VZV, Lyme disease or otogenic FP had a significant higher recovery rate (p = 0.002, p < 0.0001, p = 0.018, respectively), whereas patients with post-surgery FP and other reasons had a significant lower recovery rate (p < 0.0001). After multivariate analyses voluntary activity in first EMG, Lyme disease and post-surgery cause were identified as independent diagnostic and prognostic factors on the probability of complete recovery (all p < 0.05). CONCLUSION: Infectious causes for non-idiopathic FP like VZV reactivation and Lyme disease had best probability for complete recovery. Post-surgery FP had a worse prognosis. LEVEL OF EVIDENCE: 2.

The importance of different learning stages for motor sequence learning after stroke.

The task of learning predefined sequences of interrelated motor actions is of everyday importance and has also strong clinical importance for regaining motor function after brain lesions. A solid understanding of sequence learning in stroke patients can help clinicians to optimize and individualize rehabilitation strategies. Moreover, to investigate the impact of a focal lesion on the ability to successfully perform motor sequence learning can enhance our comprehension of the underlying physiological principles of motor sequence learning. In this article, we will first provide an overview of current concepts related to motor sequence learning in healthy subjects with focus on the involved brain areas and their assumed functions according to the temporal stage model. Subsequently, we will consider the question of what we can learn from studies investigating motor sequence learning in stroke patients. We will first focus on the implications of lesion location. Then, we will analyze whether distinct lesion locations affect specific learning stages. Finally, we will discuss the implications for clinical rehabilitation and suggest directions for further research.

The Effect of Endovascular Thrombectomy Studies on the Decision to Transfer Patients in a Telestroke Network.

Background/Introduction: In 2015, five high-quality trials demonstrated the effectiveness of endovascular thrombectomy for certain patients. Patient selection for transfer to a hub hospital is mostly focused on the patient's eligibility for a potential thrombectomy. However, it remains challenging to correctly select those patients with the highest probability of undergoing a thrombectomy. Materials and Methods: In this study, we investigated which factors promote or impede the transfer of patients and whether the impact of these factors has changed since the publication of the five randomized thrombectomy studies in 2015. We analyzed 12,048 cases of telestroke consultation from the stroke telemedicine network in Thuringia (SATELIT) and compared the decision-making process related to patient transfer based on consultations that occurred before and after 2015. Results: In both time intervals, we found that the patient's age and the identification of a proximal vessel occlusion independently influenced the decision to transfer a patient. The age factor remained unchanged over time. A known proximal intracranial vessel occlusion had a strong positive influence on the decision to transfer patients. Discussion: The decision of whether to transfer a patient is currently focused on the identification of intracranial vessel occlusion. However, the age of the patient remains an unchanged but important factor that might be overemphasized. The time elapsed from symptom onset to consultation was not found to have an independent influence on the decision-making process, so it might be underemphasized. Conclusions: The decision-making process to transfer a patient within our telestroke network has been strongly affected by the publication of the endovascular thrombectomy studies, but those studies are not solely optimized for this aim.

Knowledge, Motivation and Sustainability: Divergent Effects of a Staff Training Program on Residents and Specialists in Acute Stroke Care.

BACKGROUND: To improve the clinical efficiency of acute stroke management, we implemented a new staff training intervention. The training consisted of a case-based discussion of recent thrombolysis cases with the entire neurologic staff for 1 year. Here, we sought to determine whether the effects of this training were sustained after the discontinuation of the intervention. METHODS: All thrombolysis cases prior to the intervention (2015, 2016), during the time of training (2017) and after the discontinuation of the training (2018) were recorded and compared. The primary outcome parameter was door-to-needle time. RESULTS: Door-to-needle time decreased from 37 minutes in the preintervention period to 28 minutes during the intervention period (P < .001). After the discontinuation of training, there was a nonsignificant trend toward an increase in door-to-needle time (31 minutes). Performance remained unchanged for residents (<6 years of neurologic training; 30.8-31.2 minutes), while the performance of specialists (>6 years of neurologic training) significantly decreased (from 25.4 minutes during the intervention to 31.7 minutes after discontinuation, P = .047). By using regression analysis to control for multiple confounding factors, we found a significant association between the intervention and an improved patient outcome (P = .008). CONCLUSIONS: The present results demonstrate improved treatment of stroke patients by a regular case-based discussion of recent thrombolysis cases. After discontinuation, the effects were sustained for the residents but not for the specialists. The results suggest that improved knowledge in residents is the main reason for better performance, while the performance of specialists was more affected by motivation.

Talk About Thrombolysis. Regular Case-Based Discussions of Stroke Thrombolysis Improve Door-to-Needle Time by 20.

BACKGROUND: The outcome of stroke patients can be improved by a rapid initiation of thrombolytic therapy. Here, we sought to determine whether an additional simple but thorough case-based discussion of recent thrombolysed cases with the entire neurologic staff can improve the door-to-needle time without changes to the implemented stroke protocol. METHODS: For every performed thrombolysis, a route card, consisting of a timeline with 3 time points and target times, had to be completed by the attending neurologist. Times and reasons for delays were noted. All thrombolysed cases were then reviewed in a 14-day-rhythm with the entire neurologic staff. The responsible stroke consultant gave details and reasons for delays. Possibilities to avoid delays were then discussed with the whole team. All thrombolyses were prospectively recorded and compared with thrombolyses of the 2 preinterventional years. The primary outcome parameter was the door-to-needle time. RESULTS: The door-to-needle time decreased from 37 minutes in the preintervention period (N = 154) to 28 minutes during the intervention (N = 97; P < .001). Performance was improved for residents (<6 years of neurologic training) as well as for the specialists (>6 years of neurologic training). Improvements in the performance of specialists were significantly greater than those of residents. CONCLUSIONS: The present study demonstrates improved treatment of stroke patients by a simple, non-time-consuming intervention that combines education with a potential increase in staff motivation. This intervention is effective in a tertiary academic stroke center with a previously implemented sophisticated stroke protocol but should also improve treatment delays in primary stroke centers.

Transfer of Patients in a Telestroke Network: What Are the Relevant Factors for Making This Decision?

Background/Introduction: Current telestroke network consultations are focused on decision-making in the hyperacute stage of stroke management. The two main questions in telestroke consultations are whether thrombolysis should be initiated and whether the patient should be transferred to a hub hospital. Although guidelines exist for initiating intravenous thrombolytic therapy, the question of whether patients should be transferred is far more elusive. MATERIALS AND METHODS: In this study, we investigated the factors involved in the decision to transfer stroke patients to a hub hospital. We were particularly interested in identifying factors that promote or impede the transfer of patients. We enrolled 1,615 cases of telestroke consultation of the University Hospital Jena. RESULTS: The two main factors that independently influenced the probability of transferring a patient were the patient's age and the identification of a proximal vessel occlusion. Interestingly, factors such as the severity of symptoms and the time elapsed from symptom onset were not found to have an independent influence on the decision to transfer a patient. The transfer of most patients was justified by the possibility of performing interventional reperfusion therapy. DISCUSSION: We discuss the effectiveness of the current decision-making process and possible ways to improve decision-making for a more effective selection of patients who would benefit from transfer. CONCLUSION: The decision-making process to a transfer patient is not standardized and constitutes a trade-off between the intention to treat all possible patients while avoiding the transfer of patients without treatment options.

Initial severity of motor and non-motor disabilities in patients with facial palsy: an assessment using patient-reported outcome measures.

Patients with facial palsy (FP) not only suffer from their facial movement disorder, but also from social and psychological disabilities. These can be assessed by patient-reported outcome measures (PROMs) like the quality-of-life Short-Form 36 Item Questionnaire (SF36) or FP-specific instruments like the Facial Clinimetric Evaluation Scale (FaCE) or the Facial Disability Index (FDI). Not much is known about factors influencing PROMs in patients with FP. We identified predictors for baseline SF36, FaCE, and FDI scoring in 256 patients with unilateral peripheral FP using univariate correlation and multivariate linear regression analyses. Mean age was 52 ± 18 years. 153 patients (60 %) were female. 90 patients (31 %) and 176 patients (69 %) were first seen <90 or >90 days after onset, respectively, i.e., with acute or chronic FP. House-Brackmann grading was 3.9 ± 1.4. FaCE subscores varied from 41 ± 28 to 71 ± 26, FDI scores from 65 ± 20 to 70 ± 22, and SF36 domains from 52 ± 20 to 80 ± 24. Older age, female gender, higher House-Brackmann grading, and initial assessment >90 days after onset were independent predictors for lower FaCE subscores and partly for lower FDI subscores (all p < 0.05). Older age and female gender were best predictors for lower results in SF36 domains. Comorbidity was associated with lower SF General health perception and lower SF36 Emotional role (all p < 0.05). Specific PROMs reveal that older and female patients and patients with chronic FP suffer particularly from motor and non-motor disabilities related to FP. Comorbidity unrelated to the FP could additionally impact the quality of life of patients with FP.

Measuring eye states in functional MRI.

BACKGROUND: In many functional magnetic resonance imaging (fMRI) studies, experimental design often depends on the eye state (i.e., whether the participants had their eyes open or closed). Closed eyes during an fMRI is the general convention, particularly when patients are in a resting-state, but the eye state is difficult to verify. Although knowledge of the impact of the eye state on brain activity is steadily growing, only a few research groups have implemented standardized procedures to monitor eye movements and eye state. These procedures involve advanced methods that are costly (e.g., fMRI-compatible cameras) and often time-consuming (e.g., EEG/EOG). RESULTS: We present a simple method that distinguishes open from closed eyes utilizing functional MR images alone. The utility of this method was demonstrated on fMRI data from 14 healthy subjects who had to open and close their eyes according to a predetermined protocol (3.0 T MRI scanner, EPI sequence with 3 × 3 × 3 mm voxels, TR 2.52 s). CONCLUSION: The method presented herein is capable of extracting the movement direction of the eyes. All described methods are applicable for pre- and post-normalized MR images and are freely available through a MATLAB toolbox.

Parallel processing of somatosensory information: Evidence from dynamic causal modeling of MEG data.

The advent of methods to investigate network dynamics has led to discussion of whether somatosensory inputs are processed in serial or in parallel. Both hypotheses are supported by DCM analyses of fMRI studies. In the present study, we revisited this controversy using DCM on magnetoencephalographic (MEG) data during somatosensory stimulation. Bayesian model comparison was used to allow for direct inference on the processing stream. Additionally we varied the duration of the time-window of analyzed data after the somatosensory stimulus. This approach allowed us to explore time dependent changes in the processing stream of somatosensory information and to evaluate the consistency of results. We found that models favoring a parallel processing route best describe neural activities elicited by somatosensory stimuli. This result was consistent for different time-windows. Although it is assumed that the majority of somatosensory information is delivered to the SI, the current results indicate that at least a small part of somatosensory information is delivered in parallel to the SII. These findings emphasize the importance of data analysis with high temporal resolution.

Excitatory and inhibitory mechanisms underlying somatosensory habituation.

Habituation is a basic process of learning in which repeated exposure to a sensory stimulus leads to a decrease in the strength of neuronal activations and behavioral responses. In addition to increases in neuronal activity, sensory stimuli can also lead to decreases in neuronal activity. Until now, the effects of habituation on stimulus-induced neuronal deactivations have not been investigated. We performed functional magnetic resonance imaging in 30 healthy subjects during repetitive unilateral somatosensory stimulation and combined this analysis with a psychophysiological examination of changes in the perception threshold. Consistent with the literature, we found a time-dependent decrease of the positive blood oxygenation level-dependent (BOLD) response (indicative of habituation) in the primary somatosensory cortex (SI) contralateral to the stimulus. In contrast, the negative BOLD response (NBR) in the ipsilateral SI did not show a decrease in amplitude; instead, an increase in amplitude was found, i.e., a stronger NBR (increased response). The increased NBR was associated with an increased perception threshold of the nonstimulated hand. These findings suggest that habituation is not primarily characterized by a decrease in the neuronal response to repeated stimuli but rather a widespread change in the balance between excitatory and inhibitory effects that favors inhibitory effects.

Thalamocortical connectivity during resting state in schizophrenia.

Schizophrenia has been linked to disturbed connectivity between large-scale brain networks. Altered thalamocortical connectivity might be a major mechanism mediating regionally distributed dysfunction, yet it is only incompletely understood. We analysed functional magnetic resonance imaging data obtained during resting state from 22 DSM-IV schizophrenia patients and 22 matched healthy controls to directly assess the differences in thalamocortical functional connectivity. We identified significantly higher overall thalamocortical functional connectivity in patients, which was mostly accounted for by difference in thalamic connections to right ventrolateral prefrontal and bilateral secondary motor and sensory (superior temporal and lateral occipital) cortical areas. Voxelwise analysis showed group differences at the thalamic level to be mostly in medial and anterior thalamic nuclei and arising thalamocortical changes to be mostly due to higher positive correlations in prefrontal and superior temporal correlations, as well as absent negative correlations to sensory areas in patients. Our findings demonstrate that different types of thalamocortical dysfunction contribute to network alterations, including lack of inhibitory interaction attributed to the lack of significant negative thalamic/sensory cortical connections. These results emphasize the functional importance of the thalamus in the pathophysiology of schizophrenia.

Connecting the dots: Motor and default mode network crossroads in post-stroke motor learning deficits.

BACKGROUND: Strokes frequently result in long-term motor deficits, imposing significant personal and economic burdens. However, our understanding of the underlying neural mechanisms governing motor learning in stroke survivors remains limited - a fact that poses significant challenges to the development and optimisation of therapeutic strategies. OBJECTIVE: This study investigates the diversity in motor learning aptitude and its associated neurological mechanisms. We hypothesised that stroke patients exhibit compromised overall motor learning capacity, which is associated with altered activity and connectivity patterns in the motor- and default-mode-network in the brain. METHODS: We assessed a cohort of 40 chronic-stage, mildly impaired stroke survivors and 39 age-matched healthy controls using functional Magnetic Resonance Imaging (fMRI) and connectivity analyses. We focused on neural activity and connectivity patterns during an unilateral motor sequence learning task performed with the unimpaired or non-dominant hand. Primary outcome measures included task-induced changes in neural activity and network connectivity. RESULTS: Compared to controls, stroke patients showed significantly reduced motor learning capacity, associated with diminished cerebral lateralization. Task induced activity modulation was reduced in the motor network but increased in the default mode network. The modulated activation strength was associated with an opposing trend in task-induced functional connectivity, with increased connectivity in the motor network and decreased connectivity in the DMN. CONCLUSIONS: Stroke patients demonstrate altered neural activity and connectivity patterns during motor learning with their unaffected hand, potentially contributing to globally impaired motor learning skills. The reduced ability to lateralize cerebral activation, along with the enhanced connectivity between the right and left motor cortices in these patients, may signify maladaptive neural processes that impede motor adaptation, possibly affecting long-term rehabilitation post-stroke. The contrasting pattern of activity modulation and connectivity alteration in the default mode network suggests a nuanced role of this network in post-stroke motor learning. These insights could have significant implications for the development of customised rehabilitation strategies for stroke patients.

Perceptual plasticity is mediated by connectivity changes of the medial thalamic nucleus.

It is well known that the threshold for somatosensory perception may adapt to different inputs. Recent studies suggest the presence of a modulating effect of somatosensory inputs on the spinal dorsal horn. However, the effects of somatosensory inputs on cerebral processing and, in particular, on the functional and effective connectivity of the somatosensory brain network, are poorly understood. In this study, we investigated the longitudinal impact of somatosensory stimuli on the resting-state functional connectivity and effective connectivity of the somatosensory brain network. We performed resting-state functional magnetic resonance imaging (fMRI) in 12 healthy subjects before and after unilateral electrical median nerve stimulation. We combined this analysis with a psychophysiological examination of changes of the perception threshold. We found that the unilateral median nerve stimulation increased the perception thresholds bilaterally and increased the resting-state functional and effective connectivity between most cortical areas of the somatosensory network. The major finding, however, was a decreased resting-state functional connectivity between both secondary somatosensory cortices and the bilateral medial nuclear complex of the thalamus. This decreased connectivity was correlated with increased perception thresholds. These findings emphasize the importance of the medial thalamic nucleus for the perceptual awareness of somatosensory stimuli.

Selective zygomaticus muscle activation by ball electrodes in synkinetically reinnervated patients after facial paralysis.

Introduction: Although many different treatments were developed for facial palsy, only a few therapeutic options are available for facial synkinesis. Electrical stimulation of specific muscles via implants could be useful in restoring facial symmetry in synkinetic patients. A challenge in developing stimulation devices is finding the right stimulation location, type, and amplitude. This work assesses the ability to selectively stimulate the zygomaticus muscle (ZYG) in patients with oral-ocular synkinesis to elicit a visually detectable response of the ipsilateral corner of the mouth (COM), without causing a reaction of the orbicularis oculi muscle (OOM). We aimed to assess how close to the COM the stimulation should be delivered in order to be selective. Methods: A total of 10 patients (eight females, two males) were enrolled. Facial function was graded according to the Sunnybrook facial grading system. Needle EMG was used to test the activities of the muscles, during volitional and "unintended" movements, and the degree of synkinesis of the ZYG and OOM. Two ball electrodes connected to an external stimulator were placed on the paretic ZYG, as close as possible to the COM. Results: Independent of the waveform with which the stimulation was presented, a selective ZYG response was observed within 4.5 cm of the horizontal plane and 3 cm of the vertical plane of the COM. When the distance between the electrodes was kept to ≤2 cm, the amplitude necessary to trigger a response ranged between 3 and 6 mA when the stimulation was delivered with triangular pulses and between 2.5 and 3.5 mA for rectangular pulses. The required amplitude did not seem to be dependent on the applied phase duration (PD), as long as the PD was ≥5 ms. Conclusion: Our results show that selective stimulation of the ZYG presenting synkinetic ZYG-OOM reinnervation can be achieved using a broad PD range (25-1,000 ms) and an average amplitude ≤6 mA, which may be further decreased to 3.5 mA if the stimulation is delivered via rectangular rather than triangular waves. The most comfortable and effective results were observed with PDs between 50 and 250 ms, suggesting that this range should be selected in future studies. Clinical Trial Registration: [https://drks.de/search/de/trial/DRKS00019992], identifier (DRKS00019992).

Reward network dysfunction is associated with cognitive impairment after stroke.

Stroke survivors not only suffer from severe motor, speech and neurocognitive deficits, but in many cases also from a "lack of pleasure" and a reduced motivational level. Especially apathy and anhedonic symptoms can be linked to a dysfunction of the reward system. Rewards are considered as important co-factor for learning, so the question arises as to why and how this affects the rehabilitation of stroke patients. We investigated reward behaviour, learning ability and brain network connectivity in acute (3-7d) mild to moderate stroke patients (n = 28) and age-matched healthy controls (n = 26). Reward system activity was assessed using the Monetary Incentive Delay task (MID) during magnetoencephalography (MEG). Coherence analyses were used to demonstrate reward effects on brain functional network connectivity. The MID-task showed that stroke survivors had lower reward sensitivity and required greater monetary incentives to improve performance and showed deficits in learning improvement. MEG-analyses showed a reduced network connectivity in frontal and temporoparietal regions. All three effects (reduced reward sensitivity, reduced learning ability and altered cerebral connectivity) were found to be closely related and differed strongly from the healthy group. Our results reinforce the notion that acute stroke induces reward network dysfunction, leading to functional impairment of behavioural systems. These findings are representative of a general pattern in mild strokes and are independent of the specific lesion localisation. For stroke rehabilitation, these results represent an important point to identify the reduced learning capacity after stroke and to implement individualised recovery exercises accordingly.

Research Data Management and Data Sharing for Reproducible Research-Results of a Community Survey of the German National Research Data Infrastructure Initiative Neuroscience.

Science is changing: the volume and complexity of data are increasing, the number of studies is growing and the goal of achieving reproducible results requires new solutions for scientific data management. In the field of neuroscience, the German National Research Data Infrastructure (NFDI-Neuro) initiative aims to develop sustainable solutions for research data management (RDM). To obtain an understanding of the present RDM situation in the neuroscience community, NFDI-Neuro conducted a comprehensive survey among the neuroscience community. Here, we report and analyze the results of the survey. We focused the survey and our analysis on current needs, challenges, and opinions about RDM. The German neuroscience community perceives barriers with respect to RDM and data sharing mainly linked to (1) lack of data and metadata standards, (2) lack of community adopted provenance tracking methods, (3) lack of secure and privacy preserving research infrastructure for sensitive data, (4) lack of RDM literacy, and (5) lack of resources (time, personnel, money) for proper RDM. However, an overwhelming majority of community members (91%) indicated that they would be willing to share their data with other researchers and are interested to increase their RDM skills. Taking advantage of this willingness and overcoming the existing barriers requires the systematic development of standards, tools, and infrastructure, the provision of training, education, and support, as well as additional resources for RDM to the research community and a constant dialogue with relevant stakeholders including policy makers to leverage of a culture change through adapted incentivization and regulation.

Laryngeal electromyography: a proposal for guidelines of the European Laryngological Society.

Although recognized as a valuable diagnostic tool for more than 60 years, many laryngologists do not routinely use laryngeal electromyography (LEMG). This may be due to a persisting lack of agreement on methodology, interpretation, validity, and clinical application of LEMG. To achieve consensus in these fields, a laryngeal electromyography working group of European neurolaryngologic experts was formed in order to (1) evaluate guidelines for LEMG performance and (2) identify issues requiring further clarification. To obtain an overview of existing knowledge and research, English-language literature about LEMG was identified using Medline. Additionally, cited works not detected in the initial search were screened. Evidence-based recommendations for the performance and interpretation of LEMG and also for electrostimulation for functional evaluation were considered, as well as published reports based on expert opinion and single-institution retrospective case series. To assess the data obtained by this literature evaluation, the working group met five times and performed LEMG together on more than 20 patients. Subsequently, the results were presented and discussed at the 8th Congress of the European Laryngological Society in Vienna, Austria, September 1-4, 2010, and consensus was achieved in the following areas: (1) minimum requirements for the technical equipment required to perform and record LEMG; (2) best practical implementation of LEMG; (3) criteria for interpreting LEMG. Based on this consensus, prospective trials are planned to improve the quality of evidence guiding the proceedings of practitioners.