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The inconsistent response to transcranial electric stimulation in the stroke population is attributed to, among other factors, unknown effects of stroke lesion conductivity on stimulation strength at the targeted brain areas. Volume conduction models are promising tools to determine optimal stimulation settings. However, stroke lesion conductivity is often not considered in these models as a source of inter-subject variability. The goal of this study is to propose a method that combines MRI, EEG, and transcranial stimulation to estimate the conductivity of cortical stroke lesions experimentally. In this simulation study, lesion conductivity was estimated from scalp potentials during transcranial electric stimulation in 12 chronic stroke patients. To do so, first, we determined the stimulation configuration where scalp potentials are maximally affected by the lesion. Then, we calculated scalp potentials in a model with a fixed lesion conductivity and a model with a randomly assigned conductivity. To estimate the lesion conductivity, we minimized the error between the two models by varying the conductivity in the second model. Finally, to reflect realistic experimental conditions, we test the effect rotation of measurement electrode orientation and the effect of the number of electrodes used. We found that the algorithm converged to the correct lesion conductivity value when noise on the electrode positions was absent for all lesions. Conductivity estimation error was below 5% with realistic electrode coregistration errors of 0.1° for lesions larger than 50 ml. Higher lesion conductivities and lesion volumes were associated with smaller estimation errors. In conclusion, this method can experimentally estimate stroke lesion conductivity, improving the accuracy of volume conductor models of stroke patients and potentially leading to more effective transcranial electric stimulation configurations for this population.Background and Objective Although depression is one of the most common non-motor symptoms in essential tremor (ET), its pathogenesis and diagnosis biomarker are still unknown. Recently, machine learning multivariate pattern analysis (MVPA) combined with connectivity mapping of resting-state fMRI has provided a promising way to identify patients with depressed ET at the individual level and help to reveal the brain network pathogenesis of depression in patients with ET. Methods Based on global brain connectivity (GBC) mapping from 41 depressed ET, 49 non-depressed ET, 45 primary depression, and 43 healthy controls (HCs), multiclass Gaussian process classification (GPC) and binary support vector machine (SVM) algorithms were used to identify patients with depressed ET from non-depressed ET, primary depression, and HCs, and the accuracy and permutation tests were used to assess the classification performance. Results While the total accuracy (40.45%) of four-class GPC was poor, the four-class GPC could discriminunderlying depression in patients with ET.Introduction Esketamine (Esk) (S(+)-ketamine) is now used as an alternative to its racemic mixture, i. e., ketamine in anesthesia. Esk demonstrated more powerful potency and rapid recovery in anesthesia and less psychotomimetic side effects comparing with ketamine, but Esk could still induce psychological side effects in patients. This study was to investigate whether dexmedetomidine (Dex) can attenuate the Esk-induced neuronal hyperactivities in Kunming mice. Methods Dexmedetomidine 0.25, 0.5, and 1 mg/kg accompanied with Esk 50 mg/kg were administrated on Kunming mice to assess the anesthesia quality for 1 h. The indicators, such as time to action, duration of agitation, duration of ataxia, duration of loss pedal withdrawal reaction (PWR), duration of catalepsy, duration of righting reflex (RR) loss, duration of sedation, were recorded for 1 h after intraperitoneal administration. The c-Fos expression in the brain was detected by immunohistochemistry and Western Blot after 1 h of administration. Consideringdently increased the recovery time from anesthesia. It demonstrated that a small dose of Dex 0.25 mg/kg could be sufficient to attenuate Esk-induced psychotomimetic side effects without extension of recovery time in Kunming mice.Background Anxiety and depression remain underdiagnosed in routine clinical practice in up to two thirds of epilepsy patients despite significant impact on medical and psychosocial outcome. Barriers to adequate mental health care for epilepsy and/or psychogenic non-epileptic seizures (PNES) include a lack of integrated mental health specialists and standardized procedures. This naturalistic study outlines the procedures and outcome of a recently established psychotherapeutic service. Methods Routine screening included the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E, cut-off value > 13) and Generalized Anxiety Disorder scale (GAD-7, cut-off value > 5). Positively (above cut-off in at least one questionnaire) screened patients were seen for a standardized interview for mental health disorders and the development of a personalized treatment plan. PNES patients were seen irrespective of their screening score. Resources were provided to support self-help and access to psychotherapy. click here Patients were contacted 1 month after discharge to evaluate adherence to therapeutic recommendations. Results 120 patients were screened. Overall, 56 of 77 positively screened patients (77%) were found to have a psychiatric diagnosis through standardized interview. More epilepsy patients with an anxiety disorder had previously been undiagnosed compared to those with a depressive episode (63% vs. 30%); 24 epilepsy patients (62%) with a psychiatric comorbidity and 10 PNES patients (59%) were not receiving any mental health care. At follow-up, 16/17 (94%) epilepsy patients and 7/7 PNES patients without prior psychiatric treatment were adhering to therapeutic recommendations. Conclusion Integrating mental health specialists and establishing standardized screening and follow-up procedures improve adherence to mental health care recommendations in epilepsy and PNES patients.Nitric oxide (NO) is of fundamental importance in regulating immune, cardiovascular, reproductive, neuromuscular, and nervous system function. It is rapidly synthesized and cannot be confined, it is highly reactive, so its lifetime is measured in seconds. These distinctive properties (contrasting with classical neurotransmitters and neuromodulators) give rise to the concept of NO as a "volume transmitter," where it is generated from an active source, diffuses to interact with proteins and receptors within a sphere of influence or volume, but limited in distance and time by its short half-life. In the auditory system, the neuronal NO-synthetizing enzyme, nNOS, is highly expressed and tightly coupled to postsynaptic calcium influx at excitatory synapses. This provides a powerful activity-dependent control of postsynaptic intrinsic excitability via cGMP generation, protein kinase G activation and modulation of voltage-gated conductances. NO may also regulate vesicle mobility via retrograde signaling. This Mini Review focuses on the auditory system, but highlights general mechanisms by which NO mediates neuronal intrinsic plasticity and synaptic transmission. The dependence of NO generation on synaptic and sound-evoked activity has important local modulatory actions and NO serves as a "volume transmitter" in the auditory brainstem. It also has potentially destructive consequences during intense activity or on spill-over from other NO sources during pathological conditions, when aberrant signaling may interfere with the precisely timed and tonotopically organized auditory system.Midbrain dopaminergic neurons located in the substantia nigra and the ventral tegmental area are the main source of dopamine in the brain. They send out projections to a variety of forebrain structures, including dorsal striatum, nucleus accumbens, and prefrontal cortex (PFC), establishing the nigrostriatal, mesolimbic, and mesoprefrontal pathways, respectively. The dopaminergic input to the PFC is essential for the performance of higher cognitive functions such as working memory, attention, planning, and decision making. The gradual maturation of these cognitive skills during postnatal development correlates with the maturation of PFC local circuits, which undergo a lengthy functional remodeling process during the neonatal and adolescence stage. During this period, the mesoprefrontal dopaminergic innervation also matures the fibers are rather sparse at prenatal stages and slowly increase in density during postnatal development to finally reach a stable pattern in early adulthood. Despite the prominent role of dopamine in the regulation of PFC function, relatively little is known about how the dopaminergic innervation is established in the PFC, whether and how it influences the maturation of local circuits and how exactly it facilitates cognitive functions in the PFC. In this review, we provide an overview of the development of the mesoprefrontal dopaminergic system in rodents and primates and discuss the role of altered dopaminergic signaling in neuropsychiatric and neurodevelopmental disorders.Vertebrate hair cell (HC) systems are innervated by efferent fibers that modulate their response to external stimuli. link2 In mammals, the best studied efferent-HC synapse, the cholinergic medial olivocochlear (MOC) efferent system, makes direct synaptic contacts with HCs. The net effect of MOC activity is to hyperpolarize HCs through the activation of α9α10 nicotinic cholinergic receptors (nAChRs) and the subsequent activation of Ca2+-dependent SK2 potassium channels. A serious obstacle in research on many mammalian sensory systems in their native context is that their constituent neurons are difficult to access even in newborn animals, hampering circuit observation, mapping, or controlled manipulation. link3 By contrast, fishes and amphibians have a superficial and accessible mechanosensory system, the lateral line (LL), which circumvents many of these problems. LL responsiveness is modulated by efferent neurons which aid to distinguish between external and self-generated stimuli. One component of the LL efferent syst that an α9-containing nAChR, functionally coupled to SK channels, operates at the LL efferent synapse. In this review, we discuss the tools and findings of these recent investigations into zebrafish efferent-HC synapse, their commonalities with the mammalian counterpart and discuss several emerging areas for future studies.Microglia, which serve as the defensive interface of the nervous system, are activated in many neurological diseases. Their role as immune responding cells has been extensively studied in the past few years. Recent studies have demonstrated that neuronal feedback can be shaped by the molecular signals received and sent by microglia. Altered neuronal activity or synaptic plasticity leads to the release of various communication messages from neurons, which in turn exert effects on microglia. Research on microglia-neuron communication has thus expanded from focusing only on neurons to the neurovascular unit (NVU). This approach can be used to explore the potential mechanism of neurovascular coupling across sophisticated receptor systems and signaling cascades in health and disease. However, it remains unclear how microglia-neuron communication happens in the brain. Here, we discuss the functional contribution of microglia to synapses, neuroimmune communication, and neuronal activity. Moreover, the current state of knowledge of bidirectional control mechanisms regarding interactions between neurons and microglia are reviewed, with a focus on purinergic regulatory systems including ATP-P2RY12R signaling, ATP-adenosine-A1Rs/A2ARs, and the ATP-pannexin 1 hemichannel.

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