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Deep brain stimulation (DBS) treatment has proven effective in suppressing symptoms of rigidity, bradykinesia, and tremor in Parkinson's disease. Still, patients may suffer from disabling fluctuations in motor and non-motor symptom severity during the day. Conventional DBS treatment consists of continuous stimulation but can potentially be further optimised by adapting stimulation settings to the presence or absence of symptoms through closed-loop control. This critically relies on the use of 'physiomarkers' extracted from (neuro)physiological signals. Ideal physiomarkers for adaptive DBS (aDBS) are indicative of symptom severity, detectable in every patient, and technically suitable for implementation. In the last decades, much effort has been put into the detection of local field potential (LFP) physiomarkers and in their use in clinical practice. We conducted a research synthesis of the correlations that have been reported between LFP signal features and one or more specific PD motor symptoms. Features based on the spectral beta band (~ 13 to 30 Hz) explained ~ 17% of individual variability in bradykinesia and rigidity symptom severity. Limitations of beta band oscillations as physiomarker are discussed, and strategies for further improvement of aDBS are explored. [ABSTRACT FROM AUTHOR]

In recent decades, microelectrodes have been widely used in neuroscience to understand the mechanisms behind brain functions, as well as the relationship between neural activity and behavior, perception and cognition. However, the recording of neuronal activity over a long period of time is limited for various reasons. In this review, we briefly consider the types of penetrating chronic microelectrodes, as well as the conductive and insulating materials for microelectrode manufacturing. Additionally, we consider the effects of penetrating microelectrode implantation on brain tissue. In conclusion, we review recent advances in the field of in vivo microelectrodes. [ABSTRACT FROM AUTHOR]

Over the last two decades the combination of brain slice patch clamp electrophysiology with optogenetic stimulation has proven to be a powerful approach to analyze the architecture of neural circuits and (experience-dependent) synaptic plasticity in such networks. Using this combination of methods, originally termed channelrhodopsin-assisted circuit mapping (CRACM), a multitude of measures of synaptic functioning can be taken. The current review discusses their rationale, current applications in the field, and their associated caveats. Specifically, the review addresses: (1) How to assess the presence of synaptic connections, both in terms of ionotropic versus metabotropic receptor signaling, and in terms of mono- versus polysynaptic connectivity. (2) How to acquire and interpret measures for synaptic strength and function, like AMPAR/NMDAR, AMPAR rectification, paired-pulse ratio (PPR), coefficient of variance and input-specific quantal sizes. We also address how synaptic modulation by G protein-coupled receptors can be studied with pharmacological approaches and advanced technology. (3) Finally, we elaborate on advances on the use of dual color optogenetics in concurrent investigation of multiple synaptic pathways. Overall, with this review we seek to provide practical insights into the methods used to study neural circuits and synapses, by combining optogenetics and patch-clamp electrophysiology. [ABSTRACT FROM AUTHOR]

The article addresses concerns raised regarding a study by Whitaker and colleagues on the impact of trainee progress in radiofrequency catheter ablation (RFCA) using the CARTONET artificial intelligence system. Topics include the use of left atrial electro-anatomic mapping and its potential to enhance procedural skills; the comparison of procedural outcomes between 1- and 2-year trainees; and the exploration of other treatment modalities for atrial fibrillation.

Hodgkin and Huxley hastily published their findings (Hodgkin and Huxley [2]) in what the former called in his memoirs "a cautious note to I Nature i " (p. 135; Hodgkin [1]). The second paper (Hodgkin and Huxley [3]) followed up on the "sodium hypothesis" proposed earlier by Hodgkin and Katz ([7]). In the third of the 1952 papers, Hodgkin and Huxley showed that the permeability of the membrane behaves like conductance in an electronic circuit (Hodgkin and Huxley [4]). Five papers that defined the course of history of neuroscience: Indira M. Raman and David L. Ferster: The Annotated HODGKIN & HUXLEY - A Reader's Guide, Princeton University Press (2021). [Extracted from the article]

Cardiomyocytes (CMs) differentiated from human induced pluripotent stem cells (hiPSCs) are increasingly used in cardiac safety assessment, disease modeling and regenerative medicine. A vast majority of cardiotoxicity studies in the past have tested acute effects of compounds and drugs; however, these studies lack information on the morphological or physiological responses that may occur after prolonged exposure to a cardiotoxic compound. In this review, we focus on recent advances in chronic cardiotoxicity assays using hiPSC-CMs. We summarize recently published literature on hiPSC-CMs assays applied to chronic cardiotoxicity induced by anticancer agents, as well as non-cancer classes of drugs, including antibiotics, anti-hepatitis C virus (HCV) and antidiabetic drugs. We then review publications on the implementation of hiPSC-CMs-based assays to investigate the effects of non-pharmaceutical cardiotoxicants, such as environmental chemicals or chronic alcohol consumption. We also highlight studies demonstrating the chronic effects of smoking and implementation of hiPSC-CMs to perform genomic screens and metabolomics-based biomarker assay development. The acceptance and wide implementation of hiPSC-CMs-based assays for chronic cardiotoxicity assessment will require multi-site standardization of assay protocols, chronic cardiac maturity marker reproducibility, time points optimization, minimal cellular variation (commercial vs. lab reprogrammed), stringent and matched controls and close clinical setting resemblance. A comprehensive investigation of long-term repeated exposure-induced effects on both the structure and function of cardiomyocytes can provide mechanistic insights and recapitulate drug and environmental cardiotoxicity. [ABSTRACT FROM AUTHOR]

The ability to rapidly and systematically access knowledge stored in long‐term memory in response to incoming sensory information—that is, to derive meaning from the world—lies at the core of human cognition. Research using methods that can precisely track brain activity over time has begun to reveal the multiple cognitive and neural mechanisms that make this possible. In this article, I delineate how a process of connecting affords an effortless, continuous infusion of meaning into human perception. In a relatively invariant time window, uncovered through studies using the N400 component of the event‐related potential, incoming sensory information naturally induces a graded landscape of activation across long‐term semantic memory, creating what might be called "proto‐concepts". Connecting can be (but is not always) followed by a process of further considering those activations, wherein a set of more attentionally demanding "active comprehension" mechanisms mediate the selection, augmentation, and transformation of the initial semantic representations. The result is a limited set of more stable bindings that can be arranged in time or space, revised as needed, and brought to awareness. With this research, we are coming closer to understanding how the human brain is able to fluidly link sensation to experience, to appreciate language sequences and event structures, and, sometimes, to even predict what might be coming up next. This Presidential Address reviews several decades of work using human electrophysiological methods to build an understanding of how we comprehend the world around us. The brain is able to rapidly and pervasively connect incoming sensory information to knowledge stored in long‐term memory, a process reflected in the N400 component of the event‐related potential. Using attention, this information can then be actively considered further, creating representations that allow prediction, selection, revision, sequencing, and elaboration. [ABSTRACT FROM AUTHOR]

Several neurological diseases are accompanied by rhythmic oscillatory dysfunctions in various frequency ranges and disturbed cross-frequency relationships on regional, interregional, and whole brain levels. Knowledge of these disease-specific oscillopathies is important mainly in the context of deep brain stimulation (DBS) therapy. Electrophysiological biomarkers have been used as input signals for adaptive DBS (aDBS) as well as preoperative outcome predictors. As movement disorders, particularly Parkinson's disease (PD), are among the most frequent DBS indications, the current research of DBS is the most advanced in the movement disorders field. We reviewed the literature published mainly between 2010 and 2020 to identify the most important findings concerning the current evolution of electrophysiological biomarkers in DBS and to address future challenges for prospective research. [ABSTRACT FROM AUTHOR]

The patch-clamp technique is one of the best approaches to investigate neural excitability. Impressive improvements towards the automation of the patch-clamp technique have been made, but obvious limitations and hurdles still exist, such as parallelization, volume displacement in vivo, and long-term recording. Nanotechnologies have provided opportunities to overcome these hurdles by applying electrical devices on the nanoscale. Electrodes based on nanowires, nanotubes, and nanoscale field-effect transistors (FETs) are confirmed to be robust and less invasive tools for intracellular electrophysiological recording. Research on the interface between the nanoelectrode and cell membrane aims to reduce the seal conductance and further improve the recording quality. Many novel recording approaches advance the parallelization, and precision with reduced invasiveness, thus improving the overall intracellular recording system. The combination of nanotechnology and the present intracellular recording framework is a revolutionary and promising orientation, potentially becoming the next generation electrophysiological recording technique and replacing the conventional patch-clamp technique. Here, this paper reviews the recent advances in intracellular electrophysiological recording techniques using nanotechnology, focusing on the design of noninvasive and greatly parallelized recording systems based on nanoelectronics. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF), the commonest arrhythmia, shows associations with various disease conditions. Mounting evidence indicates that atrial fibrosis is an important part of the arrhythmogenic substrate, with an essential function in the generation of conduction abnormalities that underlie the transition from paroxysmal to persistent AF, which in turn contributes to AF perpetuation. Left atrial (LA) fibrosis is considered a possible major factor and predictor in AF treatment. The present review provides insights into LA fibrosis' association with AF. The information is focused on clinical aspects and mechanisms, clinical evaluating methods that evaluate fibrosis changes and examining possible options for the prevention of atrial fibrosis. [ABSTRACT FROM AUTHOR]

Experimental, methodological, and biological variables must be accounted for statistically to maximize accuracy and comparability of published neuroscience data. However, accounting for all variables is nigh impossible. Thus we aimed to identify particularly influential variables within published neurological data, from cat, rat, and mouse studies, via a robust statistical process. Our goal was to develop tools to improve rigor in the collection and analysis of data. We strictly constrained experimental and methodological variables and then assessed four key biological variables within motoneuron research: species, age, sex, and cell type. We quantified intraexperimental and interexperimental variances in 11 commonly reported electrophysiological properties of spinal motoneurons. We first assessed variances without accounting for biological variables and then reassessed them while accounting for all four variables. We next assessed variances with all possible combinations of these four variables. We concluded that some motoneuron properties have low intraexperimental, but high interexperimental, variance; that individual motoneuron properties are impacted differently by biological variables; and that some unexplained variances still remain. We report here the optimal combinations of biological variables to reduce interexperimental variance for all 11 parameters. We also rank each parameter by intra- and interexperimental consistency. We expect these results to assist with design of experimental and analytical methods, and to support accuracy in simulations. Furthermore, although demonstrated on spinal motoneuron electrophysiology literature, our approach is applicable to biological data from all fields of neuroscience. This approach represents an important aid to experimental design, comparison of reported data, and reduction of unexplained variance in neuroscience data. NEW & NOTEWORTHY Our meta-analysis shows the impact of species, age, sex, and cell type on lumbosacral motoneuron electrophysiological properties by thoroughly quantifying variances across literature for the first time. We quantify the variances of 11 motoneuron properties with consideration of biological variables, thus providing specific insights for motoneuron modelers and experimenters, and providing a general methodological template for the quantification of variance in neurological data with the consideration of any experimental, methodological, or biological variables of interest. [ABSTRACT FROM AUTHOR]

The posteromedial thalamus (POm) has extensive recurrent connectivity with the whisker-related primary somatosensory cortex (wS1) of rodents. However, its functional contribution to somatosensory processing in wS1 remains unclear. This article reviews several recent findings, which begin to elucidate the role of POm in sensory-evoked plasticity and discusses their implications for somatosensory processing. [ABSTRACT FROM AUTHOR]

A science writer explores bioelectricity and the developments of exciting new electrical treatments. [ABSTRACT FROM AUTHOR]

The article reviews the book "Electrophysiological Recording Techniques," edited by Robert P. Vertes and Robert W. Stackman, Jr.

A review of the book "The Spark of Life: Electricity in the Human Body," by Frances Ashcroft is presented.

A review of the book "The Spark of Life," by Frances Ashcroft is presented.

A review of the book "The Spark of Life: Electricity in the Human Body," by Frances Ashcroft is presented.

The article reviews the book "Clinical Electrophysiology: A Handbook for Neurologists."

The article reviews the book "Clinical Electrophysiology: A Handbook for Neurologists."

Reviews the book "Cardiac Electrophysiology: From Cell to Bedside" 4th Edition, edited by D. P. Zipes and J. Jalife.

Reviews the book "Current Practice of Clinical Electroencephalography," 3rd ed., edited by John S. Ebersole and Timothy A. Pedley.

Reviews the book, "Interventional Electrophysiology," 2nd ed., by Igor Singer.

Reviews the book "QT Dispersion," edited by Marek Malik and Velislay Batchvarov.

Reviews the electrophysiological software program Clampex 7.0, by Axon Instruments, Inc., of Forest City, California.

Reviews the book "Basic Cardiac Electrophysiology for the Clinician," by Jose Jalife, Mario Delmar, Jorge M. Davidenko and Justus M. B. Anumonwo.

Reviews the book "Electrophysiology of Mind: Event-Related Brain Potentials and Cognition," edited by Michael D. Rugg and Michael G.H. Coles.

Reviews the book "Electrogastrography: Methodology, Validation, and Applications," edited by R.M. Stern and K.L. Koch.

Reviews the book 'Clinical Cardiac Electrophysiology: Techniques and Interpretations,' 2nd ed., by Mark E. Josephson.

Reviews the book 'Cardiac Pacing and Electrophysiology,' 3rd ed., edited by Nabil El-Sherif and Philip Samet.

Reviews the book 'Clinical Cardiac Electrophysiology: Techniques and Interpretations,' edited by Mark E. Josephson and Stuart F. Seides.

Reviews the book "Clinical Cardiac Electrophysiology: Perioperative Considerations," edited by Carl Lynch.

Reviews the book "Clinical Electrophysiology of the Heart," by D.E. Ward and A.J. Camm.