The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform
Pedram Mohseni - One of the best experts on this subject based on the ideXlab platform.
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Generation of Stimulus Triggering From IntraCortical Spike Activity for Brain–Machine–Body Interfaces (BMBIs)
IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2017Co-Authors: Shahab Shahdoost, Randolph J. Nudo, Pedram MohseniAbstract:Brain-machine-body interfaces (BMBIs) aim to create an artificial connection in the nervous system by converting neural activity recorded from one Cortical Region to electrical stimuli delivered to another Cortical Region, spinal cord, or muscles in real-time. In particular, conditioning-mode BMBIs utilize such activity-dependent stimulation strategies to induce functional re-organization in the nervous system and promote functional recovery after injury by exploiting mechanisms underlying neuroplasticity. This paper reports on reconfigurable, field-programmable gate array (FPGA)-based implementation of a translation algorithm to extract multichannel stimulus trigger signals from intraCortical neural spike activity. The approach features digital spike discrimination based on user-set thresholding and time-amplitude windowing, decision making to support different triggering patterns for various stimulation scenarios, as well as trigger-pattern-dependent blanking schemes for robust operation in the presence of stimulus artifacts. Readily lending itself to low-power, low-area implementation for future integration, the algorithm has been synthesized on a Cyclone II FPGA using Altera's Quartus II design software and validated experimentally with prerecorded intraCortical neural spike activity from an anesthetized laboratory rat.
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An FPGA platform for generation of stimulus triggering based on intraCortical spike activity in brain-machine-body interface (BMBI) applications
2015 IEEE International Symposium on Circuits and Systems (ISCAS), 2015Co-Authors: Shahab Shahdoost, Pedram MohseniAbstract:Brain-machine-body interfaces (BMBIs) aim to create an artificial connection in the nervous system by converting neural activity recorded from one Cortical Region to electrical stimuli delivered to another Cortical Region, spinal cord, or muscles in real time. In particular, conditioning-mode BMBIs utilize such activity-dependent stimulation strategies to alter the strength of synaptic efficacy between remote Regions of the nervous system and promote functional recovery after injury by exploiting mechanisms underlying neuroplasticity. This paper presents a reconfigurable, field-programmable gate array (FPGA)-based platform that incorporates digital spike discrimination based on user-set thresholding and time-amplitude windowing, as well as decision-making circuitry to generate multichannel stimulation triggers derived from intraCortical neural spike activity. The algorithm has been synthesized on a Cyclone II FPGA using Altera's Quartus II design software and validated with prerecorded intraCortical neural spike activity from an anesthetized laboratory rat.
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ISCAS - An FPGA platform for generation of stimulus triggering based on intraCortical spike activity in brain-machine-body interface (BMBI) applications
2015 IEEE International Symposium on Circuits and Systems (ISCAS), 2015Co-Authors: Shahab Shahdoost, Pedram MohseniAbstract:Brain-machine-body interfaces (BMBIs) aim to create an artificial connection in the nervous system by converting neural activity recorded from one Cortical Region to electrical stimuli delivered to another Cortical Region, spinal cord, or muscles in real time. In particular, conditioning-mode BMBIs utilize such activity-dependent stimulation strategies to alter the strength of synaptic efficacy between remote Regions of the nervous system and promote functional recovery after injury by exploiting mechanisms underlying neuroplasticity. This paper presents a reconfigurable, field-programmable gate array (FPGA)-based platform that incorporates digital spike discrimination based on user-set thresholding and timeamplitude windowing, as well as decision-making circuitry to generate multichannel stimulation triggers derived from intraCortical neural spike activity. The algorithm has been synthesized on a Cyclone II FPGA using Altera's Quartus II design software and validated with prerecorded intraCortical neural spike activity from an anesthetized laboratory rat.
Shahab Shahdoost - One of the best experts on this subject based on the ideXlab platform.
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Generation of Stimulus Triggering From IntraCortical Spike Activity for Brain–Machine–Body Interfaces (BMBIs)
IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2017Co-Authors: Shahab Shahdoost, Randolph J. Nudo, Pedram MohseniAbstract:Brain-machine-body interfaces (BMBIs) aim to create an artificial connection in the nervous system by converting neural activity recorded from one Cortical Region to electrical stimuli delivered to another Cortical Region, spinal cord, or muscles in real-time. In particular, conditioning-mode BMBIs utilize such activity-dependent stimulation strategies to induce functional re-organization in the nervous system and promote functional recovery after injury by exploiting mechanisms underlying neuroplasticity. This paper reports on reconfigurable, field-programmable gate array (FPGA)-based implementation of a translation algorithm to extract multichannel stimulus trigger signals from intraCortical neural spike activity. The approach features digital spike discrimination based on user-set thresholding and time-amplitude windowing, decision making to support different triggering patterns for various stimulation scenarios, as well as trigger-pattern-dependent blanking schemes for robust operation in the presence of stimulus artifacts. Readily lending itself to low-power, low-area implementation for future integration, the algorithm has been synthesized on a Cyclone II FPGA using Altera's Quartus II design software and validated experimentally with prerecorded intraCortical neural spike activity from an anesthetized laboratory rat.
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An FPGA platform for generation of stimulus triggering based on intraCortical spike activity in brain-machine-body interface (BMBI) applications
2015 IEEE International Symposium on Circuits and Systems (ISCAS), 2015Co-Authors: Shahab Shahdoost, Pedram MohseniAbstract:Brain-machine-body interfaces (BMBIs) aim to create an artificial connection in the nervous system by converting neural activity recorded from one Cortical Region to electrical stimuli delivered to another Cortical Region, spinal cord, or muscles in real time. In particular, conditioning-mode BMBIs utilize such activity-dependent stimulation strategies to alter the strength of synaptic efficacy between remote Regions of the nervous system and promote functional recovery after injury by exploiting mechanisms underlying neuroplasticity. This paper presents a reconfigurable, field-programmable gate array (FPGA)-based platform that incorporates digital spike discrimination based on user-set thresholding and time-amplitude windowing, as well as decision-making circuitry to generate multichannel stimulation triggers derived from intraCortical neural spike activity. The algorithm has been synthesized on a Cyclone II FPGA using Altera's Quartus II design software and validated with prerecorded intraCortical neural spike activity from an anesthetized laboratory rat.
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ISCAS - An FPGA platform for generation of stimulus triggering based on intraCortical spike activity in brain-machine-body interface (BMBI) applications
2015 IEEE International Symposium on Circuits and Systems (ISCAS), 2015Co-Authors: Shahab Shahdoost, Pedram MohseniAbstract:Brain-machine-body interfaces (BMBIs) aim to create an artificial connection in the nervous system by converting neural activity recorded from one Cortical Region to electrical stimuli delivered to another Cortical Region, spinal cord, or muscles in real time. In particular, conditioning-mode BMBIs utilize such activity-dependent stimulation strategies to alter the strength of synaptic efficacy between remote Regions of the nervous system and promote functional recovery after injury by exploiting mechanisms underlying neuroplasticity. This paper presents a reconfigurable, field-programmable gate array (FPGA)-based platform that incorporates digital spike discrimination based on user-set thresholding and timeamplitude windowing, as well as decision-making circuitry to generate multichannel stimulation triggers derived from intraCortical neural spike activity. The algorithm has been synthesized on a Cyclone II FPGA using Altera's Quartus II design software and validated with prerecorded intraCortical neural spike activity from an anesthetized laboratory rat.
John H R Maunsell - One of the best experts on this subject based on the ideXlab platform.
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microstimulation reveals limits in detecting different signals from a local Cortical Region
Current Biology, 2010Co-Authors: Amy M Ni, John H R MaunsellAbstract:Summary Behavioral performance depends on the activity of neurons in sensory cortex, but little is known about the brain's capacity to access specific neuronal signals to guide behavior. Even the individual sensory neurons that are most sensitive to a relevant stimulus are only weakly correlated with behavior [1, 2], suggesting that behavioral decisions are based on the combined activity of groups of neurons with sensitivities well matched to task demands [3, 4]. To explore how flexibly different patterns of activity can be accessed from a given Cortical Region, we trained animals to detect electrical microstimulation of local V1 sites. By allowing the animals to become expert at the detection of microstimulation of specific V1 sites that corresponded to particular retinotopic locations, we could measure the effects of that training on the ability of those sites to support the detection of visual stimuli. Training to detect electrical activation caused a large, reversible, retinotopically localized impairment of thresholds for detecting visual stimuli. Retraining on visual detection restored normal thresholds and in turn impaired thresholds for detecting microstimulation. These results suggest that there are substantial limits to the types of signals for which a local Cortical Region can be simultaneously optimized.
Jeanpascal Lefaucheur - One of the best experts on this subject based on the ideXlab platform.
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Stroke rehabilitation using noninvasive Cortical stimulation: hemispatial neglect
Expert Review of Neurotherapeutics, 2020Co-Authors: Veit Mylius, Samar S. Ayache, Hela G. Zouari, Mehdi Aoun-sebaïti, Wassim H. Farhat, Jeanpascal LefaucheurAbstract:The rehabilitation of neuropsychological sequels of cerebral stroke such as hemispatial neglect by noninvasive Cortical stimulation (NICS) attracts increasing attention from the scientific community. The NICS techniques include primarily repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). They are based on the concept of either reactivating a hypoactive Cortical Region affected by the stroke (the right hemisphere in case of neglect) or reducing Cortical hyperactivity of the corresponding Cortical Region in the contralateral hemisphere (the left hemisphere). In the studies published to date on the topic of neglect rehabilitation, rTMS was used to inhibit the left parietal cortex and tDCS to either activate the right or inhibit the left parietal cortex. Sham-controlled NICS studies assessed short-term effects, whereas long-term effects were only assessed in noncontrolled rTMS studies. Further controlled studies of large series of patients are necessary to ...
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relieving peripheral neuropathic pain by increasing the power ratio of low β over high β activities in the central Cortical Region with eeg based neurofeedback study protocol for a controlled pilot trial smrpain study
Neurophysiologie Clinique-clinical Neurophysiology, 2020Co-Authors: Julie Bismuth, Francois Vialatte, Jeanpascal LefaucheurAbstract:Summary Background Chronic neuropathic pain associated with peripheral neuropathies cannot be attributed solely to lesions of peripheral sensory axons and likely involves alteration in the processing of nociceptive information in the central nervous system in most patients. Few data are available regarding EEG correlates of chronic neuropathic pain. The fact is that effective Cortical neuromodulation strategies to treat neuropathic pain target the precentral Cortical Region, i.e. a Cortical area corresponding to the motor cortex. It is not known how these strategies might modulate brain rhythms in the central Cortical Region, but it can be speculated that sensorimotor rhythms (SMRs) are modified. Another potent way of modulating Cortical rhythms is to use EEG-based neurofeedback (NFB). Rare studies previously aimed at relieving neuropathic pain using EEG-NFB training. Methods/Design The objective of this single-centre, single-blinded, randomized controlled pilot study is to assess the value of an EEG-NFB procedure to relieve chronic neuropathic pain in patients with painful peripheral neuropathy. A series of 32 patients will be randomly assigned to one of the two following EEG-NFB protocols, aimed at increasing either the low-β(SMR)/high-β ratio (n = 16) or the α(μ)/θ ratio (n = 16) at central (rolandic) Cortical level. Various clinical outcome measures will be collected before and one week after 12 EEG-NFB sessions performed over 4 weeks. Resting-state EEG will also be recorded immediately before and after each NFB session. The primary endpoint will be the change in the impact of pain on patient's daily functioning, as assessed on the Interference Scale of the short form of the Brief Pain Inventory. Discussion The value of EEG-NFB procedures to relieve neuropathic pain has been rarely studied. This pilot study will attempt to show the value of endogenous modulation of brain rhythms in the central (rolandic) Region in the frequency band corresponding to the frequency of stimulation currently used by therapeutic motor cortex stimulation. In the case of significant clinical benefit produced by the low-β(SMR)/high-β ratio increasing strategy, this work could pave the way for using EEG-NFB training within the armamentarium of neuropathic pain therapy.
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intraoperative neurophysiologic mapping of the central Cortical Region for epidural electrode placement in the treatment of neuropathic pain by motor cortex stimulation
Brain Stimulation, 2009Co-Authors: Jeanpascal Lefaucheur, Daniel Ciampi De AndradeAbstract:Neuropathic pain results from injury to the central or peripheral nervous system and can prove itself refractory to classical medical treatment by anticonvulsants and antidepressants. In such cases, motor cortex stimulation is among the neurostimulation techniques available for its symptomatic control. This technique is based on surgical implantation of electrodes over the motor Cortical representation of the painful area. Image-guided navigation is used for precise identification of the motor cortex intraoperatively, but proper placement of the electrodes is usually ensured by electrophysiologic mapping. This article details the intraoperative electrophysiologic procedure that we currently use for refining electrode placement in the epidural space, including the recording of somatosensory and motor-evoked potentials (MEPs). Various procedures have been reported and some groups are using direct Cortical mapping and subdural electrode placement rather than epidural. Our method is one of several proposed techniques and is mostly based on intraoperative MEP mapping in response to monopolar (anodal) epidural stimulation of the cortex. The limit of this approach is that MEPs cannot be recorded in patients with total or severe motor deficit. We have shown that intraoperative mapping of the Cortical Region corresponding to the painful area by recording MEPs could help select contacts to be activated for chronic stimulation. Therefore, the patients in whom intraoperative MEP mapping is possible could benefit from this technique, at least if we consider that it improves the accuracy of electrode placement and that motor cortex stimulation efficacy critically depends on this placement.
T. Yoshimoto - One of the best experts on this subject based on the ideXlab platform.
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ICIP (3) - Estimation Of Neuromagnetic Source Location In The Cortical Region Using MR Images
Proceedings of International Conference on Image Processing, 1997Co-Authors: K. Mine, N. Niki, N. Nakasato, T. YoshimotoAbstract:We present an estimation for location of the neuromagnetic source in the Cortical Region using MR images. Magnetic fields of the brain are due to neural activity. As there are many neurons on the cortex, we regard it as a prime candidate for source location. The cortex is extracted from MR images. We assume that the points on the extracted cortex are current dipoles and all the acquired points are considered as candidate sources. We then perform the estimation on the extracted cortex by means of the MUltiple SIgnal Classification (MUSIC) method. We apply this algorithm to real human brain data.
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Neuromagnetic source location estimation in the Cortical Region using MR images
1997 IEEE Nuclear Science Symposium Conference Record, 1997Co-Authors: M. Nobuta, K. Mino, N. Niki, N. Nakasato, T. YoshimotoAbstract:The authors present neuromagnetic source location estimation in the Cortical Region using MR images. As there are many neurons on the cortex, the authors regard it as a prime candidate for source location. The cortex is extracted from MR images. The authors assume that the points on the extracted cortex are current dipoles and all the acquired points are considered as candidate sources. The authors then perform the estimation on the extracted cortex by means of the MUltiple SIgnal Classification (MUSIC) method. They apply this algorithm to real human brain data.
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Estimation of neuromagnetic source location in the Cortical Region using MR images
Proceedings of International Conference on Image Processing, 1997Co-Authors: K. Mino, N. Niki, N. Nakasato, T. YoshimotoAbstract:We present an estimation for location of the neuromagnetic source in the Cortical Region using MR images. Magnetic fields of the brain are due to neural activity. As there are many neurons on the cortex, we regard it as a prime candidate for source location. The cortex is extracted from MR images. We assume that the points on the extracted cortex are current dipoles and all the acquired points are considered as candidate sources. We then perform the estimation on the extracted cortex by means of the MUltiple SIgnal Classification (MUSIC) method. We apply this algorithm to real human brain data.
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ICIP (2) - A magnetic source estimation in the Cortical Region
Proceedings of 3rd IEEE International Conference on Image Processing, 1996Co-Authors: K. Mino, N. Niki, N. Nakasato, T. YoshimotoAbstract:The Region for estimation is limited to the surface of the cortex. Considering this limitation, the cortex is extracted from MR images. We assume that the points on the extracted cortex are current dipoles. All the acquired points are considered as candidate sources. We perform the estimation by means of the multiple signal classification (MUSIC) method which is applied to the limited Region. In the MUSIC method, the measured magnetic field data is divided into two subspaces, the signal subspace and the noise subspace. The minimum description length (MDL) criterion is used for this division.
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A magnetic source estimation in the Cortical Region
Proceedings of 3rd IEEE International Conference on Image Processing, 1996Co-Authors: K. Mino, N. Niki, N. Nakasato, T. YoshimotoAbstract:The Region for estimation is limited to the surface of the cortex. Considering this limitation, the cortex is extracted from MR images. We assume that the points on the extracted cortex are current dipoles. All the acquired points are considered as candidate sources. We perform the estimation by means of the multiple signal classification (MUSIC) method which is applied to the limited Region. In the MUSIC method, the measured magnetic field data is divided into two subspaces, the signal subspace and the noise subspace. The minimum description length (MDL) criterion is used for this division.
