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Workman posted an update 7 months, 3 weeks ago
Cortical oscillations have been proposed to play a functional role in speech and music perception, attentional selection and working memory, via the mechanism of neural entrainment. One of the properties of neural entrainment that is often taken for granted is that its modulatory effect on ongoing oscillations outlasts rhythmic stimulation. We tested the existence of this phenomenon by studying cortical neural oscillations during and after presentation of melodic stimuli in a passive perception paradigm. Melodies were composed of ∼60 and ∼80 Hz tones embedded in a 2.5 Hz stream. Using intracranial and surface recordings in male and female humans, we reveal persistent oscillatory activity in the high-gamma band in response to the tones throughout the cortex, well beyond auditory regions. By contrast, in response to the 2.5 Hz stream, no persistent activity in any frequency band was observed. We further show that our data are well-captured by a model of damped harmonic oscillator and can be classified into thres but rarely used in neuroscience.Human language learning differs significantly across individuals in the process and ultimate attainment. Although decades of research exploring the neural substrates of language learning have identified distinct and overlapping neural networks subserving learning of different components, the neural mechanisms that drive the large inter-individual differences are still far from being understood. Here we examine to what extent the neural dynamics of multiple brain networks in men and women across sessions of training contribute to explaining individual differences in learning multiple linguistic components (i.e., vocabulary, morphology, and phrase and sentence structures) of an artificial language in a seven-day training and imaging paradigm with functional Magnetic Resonance Imaging. With machine-learning and predictive modeling, neural activation patterns across training sessions were highly predictive of individual learning success profiles derived from the four components. We identified four neural learningponents. This study demonstrates that the dynamics of multiple brain networks across four imaging sessions of a seven-day artificial language training contribute to individual differences in learning-outcome profiles derived from four language components. With machine-learning predictive modeling, we identified four neural learning networks, including the Perisylvian, frontoparietal, salience, and default-mode networks that contribute to predicting individual learning-outcome profiles and revealed language-component-general and component-specific prediction patterns across training sessions. These findings provide significant insights in understanding training-dependent neural dynamics underlying individual differences in learning success across language components.The α7-type nicotinic acetylcholine receptor is one of the most unique and interesting of all the members of the cys-loop superfamily of ligand-gated ion channels. Since it was first identified initially as a binding site for α-bungarotoxin in mammalian brain and later as a functional homomeric receptor with relatively high calcium permeability, it has been pursued as a potential therapeutic target for numerous indications, from Alzheimer disease to asthma. In this review, we discuss the history and state of the art for targeting α7 receptors, beginning with subtype-selective agonists and the basic pharmacophore for the selective activation of α7 receptors. A key feature of α7 receptors is their rapid desensitization by standard “orthosteric” agonist, and we discuss insights into the conformational landscape of α7 receptors that has been gained by the development of ligands binding to allosteric sites. Some of these sites are targeted by positive allosteric modulators that have a wide range of effects on the activation profile of the receptors. Other sites are targeted by direct allosteric agonist or antagonists. We include a perspective on the potential importance of α7 receptors for metabotropic as well as ionotropic signaling. We outline the challenges that exist for future development of drugs to target this important receptor and approaches that may be considered to address those challenges. SIGNIFICANCE STATEMENT The α7-type nicotinic acetylcholine receptor (nAChR) is acknowledged as a potentially important therapeutic target with functional properties associated with both ionotropic and metabotropic signaling. The functional properties of α7 nAChR can be regulated in diverse ways with the variety of orthosteric and allosteric ligands described in this review.
To report the clinical, neuroimaging, and antibody associations in patients with autoimmune encephalitis (AE) and thymoma.
A retrospective cohort study of 43 patients was conducted. Antibody determination and immunoprecipitation to characterize novel antigens were performed using reported techniques.
Patients’ median age was 52 years (range 23-88 years). Forty (93%) had neuronal surface antibodies gamma-aminobutyric acid receptor A (GABA
R) (15), amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) (13), contactin-associated protein-like 2 (CASPR2) (4), leucine-rich, glioma inactivated 1 (LGI1) (3), glycine receptor (GlyR) (3), and unknown antigens (2). Concurrent antibodies against intracellular antigens occurred in 13 (30%; 9 anti-collapsin response mediator protein 5 [CRMP5]) and were more frequent in anti-AMPAR encephalitis (54% vs 20%;
= 0.037). The most common clinical presentation was encephalitis with multiple T2/fluid-attenuated inversion recovery hyperintense lesions in 23 ( AE and occurred more frequently in Japanese patients.
AE in patients with thymoma include several clinical-radiologic syndromes that vary according to the associated antibodies. Anti-GABAAR encephalitis was the most frequent AE and occurred more frequently in Japanese patients.
To evaluate the aryl hydrocarbon receptor (AHR)-dependent transforming growth factor alpha (TGF-α)/vascular endothelial growth factor B (VEGF-B) ratio, which regulates the effects of metabolic, dietary, and microbial factors on acute and chronic CNS inflammation, as a potential marker in multiple sclerosis (MS).
TGF-α, VEGF-B, and AHR agonistic activity were determined in serum of 252 patients with relapsing-remitting (RR) MS, primary and secondary progressive MS, as well as during active disease (clinically isolated syndrome [CIS] and RRMS relapse).
The TGF-α/VEGF-B ratio and AHR agonistic activity were decreased in all MS subgroups with a stable disease course as compared to controls. Pomalidomide supplier During active CNS inflammation in CIS and RRMS relapse, the TGF-α/VEGF-B ratio and AHR agonistic activity were increased. Conversely, in patients with minimal clinical impairment despite long-standing disease, the TGF-α/VEGF-B ratio and AHR agonistic activity were unaltered. Finally, the TGF-α/VEGF-B ratio and AHR agonistic activity correlated with neurologic impairment and time to conversion from CIS to MS.