Spontaneous activity and evoked responses of cerebellar cortical neurons to vagal and limb nerve stimulation in pigeons

1976 ◽  
Vol 7 (4) ◽  
pp. 294-299 ◽  
Author(s):  
O. V. Levchuk
Keyword(s):  
Spontaneous Activity ◽  
Nerve Stimulation ◽  
Cortical Neurons ◽  
Evoked Responses

Effects of external trigeminal nerve stimulation (eTNS) on laser evoked cortical potentials (LEP): A pilot study in migraine patients and controls

Cephalalgia ◽  
2017 ◽  
Vol 38 (7) ◽  
pp. 1245-1256 ◽  
Author(s):  
Eleonora Vecchio ◽  
Eleonora Gentile ◽  
Giovanni Franco ◽  
Katia Ricci ◽  
Marina de Tommaso
Keyword(s):  
Pilot Study ◽  
Nerve Stimulation ◽  
Migraine Without Aura ◽  
Anterior Cingulate ◽  
Evoked Responses ◽  
The Real ◽  
Sham Stimulation ◽  
Primary Headache Disorders ◽  
Transcutaneous Nerve Stimulation ◽  
The Right

Background Transcutaneous external supraorbital nerve stimulation has emerged as a treatment option for primary headache disorders, though its action mechanism is still unclear. Study aim In this randomized, sham-controlled pilot study we aimed to test the effects of a single external transcutaneous nerve stimulation session on pain perception and cortical responses induced by painful laser stimuli delivered to the right forehead and the right hand in a cohort of migraine without aura patients and healthy controls. Methods Seventeen migraine without aura patients and 21 age- and sex-matched controls were selected and randomly assigned to a real or sham external transcutaneous nerve stimulation single stimulation session. The external transcutaneous nerve stimulation was delivered with a self-adhesive electrode placed on the forehead and generating a 60 Hz pulse at 16 mA intensity for 20 minutes. For sham stimulation, we used 2 mA intensity. Laser evoked responses were recorded from 21 scalp electrodes in basal condition (T0), during external transcutaneous nerve stimulation and sham stimulation (T1), and immediately after these (T2). The laser evoked responses were analyzed by LORETA software. Results The real external transcutaneous nerve stimulation reduced the trigeminal N2P2 amplitude in migraine and control groups significantly in respect to placebo. The real stimulation was associated with lower activity in the anterior cingulate cortex under trigeminal laser stimuli. The pattern of LEP-reduced habituation was reverted by real and sham transcutaneous stimulation in migraine patients. Conclusions The present results could suggest that the external transcutaneous nerve stimulation may interfere with the threshold and the extent of trigeminal system activation, with a mechanism of potential utility in the resolution and prevention of migraine attacks.

Development, learning and memory in large random networks of cortical neurons: lessons beyond anatomy

2002 ◽  
Vol 35 (1) ◽  
pp. 63-87 ◽  
Author(s):  
Shimon Marom ◽  
Goded Shahaf
Keyword(s):  
Functional Connectivity ◽  
Spontaneous Activity ◽  
Learning And Memory ◽  
Cortical Neurons ◽  
Ex Vivo ◽  
Adaptive Responses ◽  
Cortical Networks ◽  
Neural Learning ◽  
Wide Range ◽  
Activity Dependent

1. Introduction 631.1 Outline 631.2 Universals versus realizations in the study of learning and memory 642. Large random cortical networks developing ex vivo 652.1 Preparation 652.2 Measuring electrical activity 673. Spontaneous development 693.1 Activity 693.2 Connectivity 704. Consequences of spontaneous activity: pharmacological manipulations 724.1 Structural consequences 724.2 Functional consequences 735. Effects of stimulation 745.1 Response to focal stimulation 745.2 Stimulation-induced changes in connectivity 746. Embedding functionality in real neural networks 776.1 Facing the physiological definition of ‘reward’: two classes of theories 786.2 Closing the loop 797. Concluding remarks 848. Acknowledgments 859. References 85The phenomena of learning and memory are inherent to neural systems that differ from each other markedly. The differences, at the molecular, cellular and anatomical levels, reflect the wealth of possible instantiations of two neural learning and memory universals: (i) an extensive functional connectivity that enables a large repertoire of possible responses to stimuli; and (ii) sensitivity of the functional connectivity to activity, allowing for selection of adaptive responses. These universals can now be fully realized in ex-vivo developing neuronal networks due to advances in multi-electrode recording techniques and desktop computing. Applied to the study of ex-vivo networks of neurons, these approaches provide a unique view into learning and memory in networks, over a wide range of spatio-temporal scales. In this review, we summarize experimental data obtained from large random developing ex-vivo cortical networks. We describe how these networks are prepared, their structure, stages of functional development, and the forms of spontaneous activity they exhibit (Sections 2–4). In Section 5 we describe studies that seek to characterize the rules of activity-dependent changes in neural ensembles and their relation to monosynaptic rules. In Section 6, we demonstrate that it is possible to embed functionality into ex-vivo networks, that is, to teach them to perform desired firing patterns in both time and space. This requires ‘closing a loop’ between the network and the environment. Section 7 emphasizes the potential of ex-vivo developing cortical networks in the study of neural learning and memory universals. This may be achieved by combining closed loop experiments and ensemble-defined rules of activity-dependent change.

scholarly journals Spontaneous dynamics of neural networks in deep layers of prefrontal cortex

2017 ◽  
Vol 117 (4) ◽  
pp. 1581-1594 ◽  
Author(s):  
Andrew S. Blaeser ◽  
Barry W. Connors ◽  
Arto V. Nurmikko
Keyword(s):  
Prefrontal Cortex ◽  
Spontaneous Activity ◽  
Calcium Imaging ◽  
Cortical Neurons ◽  
Rhythmic Activity ◽  
Network Activity ◽  
Local Networks ◽  
Spatiotemporal Scale ◽  
Deep Layers ◽  
Delta Oscillations

Cortical systems maintain and process information through the sustained activation of recurrent local networks of neurons. Layer 5 is known to have a major role in generating the recurrent activation associated with these functions, but relatively little is known about its intrinsic dynamics at the mesoscopic level of large numbers of neighboring neurons. Using calcium imaging, we measured the spontaneous activity of networks of deep-layer medial prefrontal cortical neurons in an acute slice model. Inferring the simultaneous activity of tens of neighboring neurons, we found that while the majority showed only sporadic activity, a subset of neurons engaged in sustained delta frequency rhythmic activity. Spontaneous activity under baseline conditions was weakly correlated between pairs of neurons, and rhythmic neurons showed little coherence in their oscillations. However, we consistently observed brief bouts of highly synchronous activity that must be attributed to network activity. NMDA-mediated stimulation enhanced rhythmicity, synchrony, and correlation within these local networks. These results characterize spontaneous prefrontal activity at a previously unexplored spatiotemporal scale and suggest that medial prefrontal cortex can act as an intrinsic generator of delta oscillations. NEW & NOTEWORTHY Using calcium imaging and a novel analytic framework, we characterized the spontaneous and NMDA-evoked activity of layer 5 prefrontal cortex at a largely unexplored spatiotemporal scale. Our results suggest that the mPFC microcircuitry is capable of intrinsically generating delta oscillations and sustaining synchronized network activity that is potentially relevant for understanding its contribution to cognitive processes.

Spinal and pudendal nerve modulation of human corticoanal motor pathways

1998 ◽  
Vol 274 (2) ◽  
pp. G419-G423 ◽  
Author(s):  
Shaheen Hamdy ◽  
Paul Enck ◽  
Qasim Aziz ◽  
John C. Rothwell ◽  
Samet Uengoergil ◽  
...  
Keyword(s):  
Anal Sphincter ◽  
Nerve Stimulation ◽  
External Anal Sphincter ◽  
Neural Control ◽  
Pudendal Nerve ◽  
Cortical Stimulation ◽  
Evoked Responses ◽  
Pudendal Nerve Stimulation ◽  
Sphincter Function ◽  
Sensorimotor Interactions

We investigated the effects of lumbosacral and pudendal nerve stimulation on the corticofugal pathways to the human external anal sphincter. In 11 healthy subjects, anal sphincter electromyographic responses, evoked to transcranial magnetic stimulation of the motor cortex, were recorded 5–500 ms after lumbosacral root or pudendal nerve stimulation. Lumbosacral and pudendal nerve stimulation alone evoked responses with amplitudes of 293 ± 73 and 401 ± 153 μV and latencies of 3.2 ± 0.2 and 2.2 ± 0.2 ms, respectively. Cortical stimulation also evoked responses with amplitudes of 351 ± 104 μV and latencies of 20.9 ± 1.1 ms. When lumbosacral or pudendal nerve stimulation preceded cortical stimulation, the cortically evoked responses were facilitated ( P < 0.01), with the effect appearing greatest at 5–20 ms after both lumbosacral and pudendal excitation and at 50–100 ms after lumbosacral excitation alone. Our results demonstrate that cortical pathways to the external anal sphincter are facilitated by prior lumbosacral and pudendal nerve stimulation, indicating that sensorimotor interactions are important in the central neural control of sphincter function.

Use of Antidromic Recording to Monitor Facial Nerve Function Intraoperatively

Neurosurgery ◽  
1985 ◽  
Vol 16 (4) ◽  
pp. 458-462 ◽  
Author(s):  
Isabelle L. Richmond ◽  
Michael Mahla
Keyword(s):  
Facial Nerve ◽  
Nerve Stimulation ◽  
Action Potentials ◽  
Muscle Relaxants ◽  
Mechanical Trauma ◽  
Evoked Responses ◽  
Nerve Function ◽  
Facial Nerve Function ◽  
Nerve Activity ◽  
Nerve Action

Abstract This report describes a technique for monitoring facial nerve activity intraoperatively utilizing antidromic nerve stimulation and sequential averaging of the evoked responses. Compound facial nerve action potentials are obtained reliably even in the presence of paralyzing doses of muscle relaxants, which render the conventional methods useless. The electrophysiological setup is straightforward, and we utilize the same sequential averaging equipment with which we monitor cortical evoked responses intraoperatively. This technique facilitates identification of the facial nerve in large cerebellopontine angel tumors with minimal mechanical trauma. Recordings from eight clinical cases are presented to illustrate the reliability and reproducibility of this technique.

Interaction of electrically evoked responses in networks of dissociated cortical neurons

2009 ◽  
Vol 80 (3) ◽  
Author(s):  
Pieter Laurens Baljon ◽  
Michela Chiappalone ◽  
Sergio Martinoia
Keyword(s):  
Cortical Neurons ◽  
Evoked Responses ◽  
Dissociated Cortical Neurons

scholarly journals Quantitative differences in developmental profiles of spontaneous activity in cortical and hippocampal cultures

2014 ◽  
Author(s):  
Paul Charlesworth ◽  
Ellese Cotterill ◽  
Andrew Morton ◽  
Seth Grant ◽  
Stephen Eglen
Keyword(s):  
Spontaneous Activity ◽  
Cortical Neurons ◽  
Activity Patterns ◽  
Machine Learning Techniques ◽  
Multielectrode Arrays ◽  
Cortical Networks ◽  
Hippocampal Cultures ◽  
Hippocampal Networks ◽  
Cultured Networks

Background: Neural circuits can spontaneously generate complex spatiotemporal firing patterns during development. This spontaneous activity is thought to help guide development of the nervous system. In this study, we had two aims. First, to characterise the changes in spontaneous activity in cultures of developing networks of either hippocampal or cortical neurons dissociated from mouse. Second, to assess whether there are any functional differences in the patterns of activity in hippocampal and cortical networks. Results: We used multielectrode arrays to record the development of spontaneous activity in cultured networks of either hippocampal or cortical neurons every two or three days for the first month after plating. Within a few days of culturing, networks exhibited spontaneous activity. This activity strengthened and then stabilised typically around 21 days in vitro. We quantified the activity patterns in hippocampal and cortical networks using eleven features. Three out of eleven features showed striking differences in activity between hippocampal and cortical networks. 1: Interburst intervals are less variable in spike trains from hippocampal cultures. 2: Hippocampal networks have higher correlations. 3: Hippocampal networks generate more robust theta bursting patterns. Machine learning techniques confirmed that these differences in patterning are sufficient to reliably classify recordings at any given age as either hippocampal or cortical networks. Conclusions: Although cultured networks of hippocampal and cortical networks both generate spontaneous activity that changes over time, at any given time we can reliably detect differences in the activity patterns. We anticipate that this quantitative framework could have applications in many areas, including neurotoxicity testing and for characterising phenotype of different mutant mice. All code and data relating to this report are freely available for others to use.

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