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Multi-Electrode Array Technologies for Neuroscience and Cardiology
Published in Lajos P. Balogh, Nano-Enabled Medical Applications, 2020
At present, the prime methodology for studying neuronal circuit-connectivity, physiology and pathology under in vitro or in vivo conditions is by using substrate-integrated microelectrode arrays. Although this methodology permits simultaneous, cell-non-invasive, long-term recordings of extracellular field potentials generated by action potentials, it is ‘blind’ to subthreshold synaptic potentials generated by single cells. On the other hand, intracellular recordings of the full electrophysiological repertoire (subthreshold synaptic potentials, membrane oscillations and action potentials) are, at present, obtained only by sharp or patch microelectrodes. These, however, are limited to single cells at a time and for short durations. Recently a number of laboratories began to merge the advantages of extracellular microelectrode arrays and intracellular microelectrodes. This Review describes the novel approaches, identifying their strengths and limitations from the point of view of the end users—with the intention to help steer the bioengineering efforts towards the needs of brain-circuit research.
Review of the Human Brain and EEG Signals
Published in Teodiano Freire Bastos-Filho, Introduction to Non-Invasive EEG-Based Brain–Computer Interfaces for Assistive Technologies, 2020
Alessandro Botti Benevides, Alan Silva da Paz Floriano, Mario Sarcinelli-Filho, Teodiano Freire Bastos-Filho
The EEG or electroencephalography is the recording of the electrical activity of a large population of neurons (several million neurons) of the cerebral cortex measured on the surface of the scalp using electrodes. This noninvasive technique is most usual; however, much more accurate neuronal activity can be obtained by introducing the electrode within the brain tissue (depth recording) or by placing electrodes on the exposed surface of the brain, which is called electrocorticogram (ECoG) [7]. These implantable electrodes can be formed by microelectrode array (e.g., 4 × 4 mm) with about 100 electrodes of 1.5 mm in length, able to register between 100 and 200 neurons [14,15].
Bidirectional Neural Interfaces
Published in Chang S. Nam, Anton Nijholt, Fabien Lotte, Brain–Computer Interfaces Handbook, 2018
Mikhail A. Lebedev, Alexei Ossadtchi
In Evarts’ classical settings, usually just one neuron would be recorded at a time. This is fine for certain neurophysiological inquiries but insufficient to achieve an accurate performance of an NI in real time. In the mid-1990s, Miguel Nicolelis and John Chapin pioneered recordings from many neurons simultaneously using multielectrode implants (Chapin et al. 1999; Nicolelis et al. 1995); they were also the first to incorporate this method in an NI (Chapin et al. 1999). Currently, multielectrode recordings are the mainstream approach to NIs in nonhuman primates (Krüger et al. 2010; Schwarz et al. 2014). Multielectrode NIs have also been tested in humans (Bouton et al. 2016; Collinger et al. 2013; Hochberg et al. 2006, 2012) using the implant, called Utah array (Campbell et al. 1991). Chronically implanted microelectrode arrays can both record and electrically stimulate brain tissue (Bensmaia & Miller 2014; O’Doherty et al. 2011; Tabot et al. 2013).
Cannabis-like activity of Zornia latifolia Sm. detected in vitro on rat cortical neurons: major role of the flavone syzalterin
Published in Drug and Chemical Toxicology, 2022
Susanna Alloisio, Marco Clericuzio, Mario Nobile, Annalisa Salis, Gianluca Damonte, Claudia Canali, Ana Paula Fortuna-Perez, Laura Cornara, Bruno Burlando
The presence on the market of new psychoactive substances raises the need for an in vitro screening of possible effects on the central nervous system. In recent years, in vitro cultures of neurons grown on microelectrode arrays (MEAs) have proved to be suitable for neurotoxicity screening of chemicals, pharmaceuticals, drugs, and new psychoactive drugs (Nicolas et al. 2014, Alloisio et al. 2015, Hondebrink et al. 2016, Vassallo et al. 2017, Strickland et al. 2018). Specific targets, such as neurotransmitter receptors or transporters, are sometimes underrepresented in this in vitro model, but nevertheless, it is always possible to achieve an integrated endpoint, since MEA recordings represent the sum of the effects on all the targets affected within the neuronal network.
Advances in stem cell therapy for amyotrophic lateral sclerosis
Published in Expert Opinion on Biological Therapy, 2018
Letizia Mazzini, Daniela Ferrari, Pavle R Andjus, Leonora Buzanska, Roberto Cantello, Fabiola De Marchi, Maurizio Gelati, Rashid Giniatullin, Joel C. Glover, Mariagrazia Grilli, Elena N. Kozlova, Margherita Maioli, Dinko Mitrečić, Augustas Pivoriunas, Rosario Sanchez-Pernaute, Anna Sarnowska, Angelo L. Vescovi
The assessment of functional phenotypes in in vitro models can be a challenge. Electrophysiological abnormalities in MNs may be an early hallmark of ALS disease progression. Hence, assays that can be used to test electrical properties and functions are likely to be pivotal in the characterization of disease mechanisms. Compared to patch-clamp recording and microelectrode arrays, optical recording of electrical events provides several advantages. For example, voltage sensitive dye imaging permits the recording of membrane potential at submillisecond resolution, sufficient to distinguish the fine temporal structure of electrical signals, and can be used to assess both excitatory and inhibitory synaptic interactions and depolarizing and hyperpolarizing neurotransmitter and drug actions [78].
Perspectives on the current developments with neuromodulation for the treatment of epilepsy
Published in Expert Review of Neurotherapeutics, 2020
Churl-Su Kwon, Nathalie Jetté, Saadi Ghatan
ANT DBS and RNS in long-term follow-up studies report approximately a 65% reduction in seizures [40,47], with continued improvement over time in the RNS system and a suggestion of plasticity and a therapeutic benefit from ongoing, repetitive training by the device [47]. The closed-loop RNS system delivers therapeutic stimulation conditional on seizure detection by electrocorticographic correlate; compared to DBS it may result in superior efficacy and cause fewer side effects. A few centers across the US are currently targeting modulatory nodes such as the ANT in response to seizure detection with RNS and have shown feasibility, safety and good tolerance [52]. Further studies are needed to determine optimal stimulation parameters and the true efficacy of RNS targeting the ANT. Microelectrode arrays have been used extensively for single/multi-unit recordings and stimulation on brain–machine interfaces [53]. Microelectrodes have the advantage of having the capability of delivering numerous spatio-temporal patterns of stimulation, which is not possible with DBS. Differentiating states associated with seizures with detection of theta band activity and continuous multimicroelectrode stimulation have been explored [54] and it is plausible that the RNS system can be customized to undertake this. More recently a 128-channel wireless artifact-free neuromodulation device has been developed that is both wireless and autonomous, adjusting stimulation parameters in real-time, within a closed-loop system used in a non-human primate model [55]. Discoveries such as this will continue to help evolve neuromodulatory investigation and stimulation-based treatment.