Ephaptic coupling of cortical neurons. Article (PDF Available) in Nature Neuroscience 14(2) · February with Reads. Request PDF on ResearchGate | Ephaptic Coupling of Cortical Neurons: Possible Contribution of Astroglial Magnetic Fields? | The close. Yet the extracellular field activity feeds back onto the electrical potential across the neuronal membrane via ephaptic coupling (Jefferys et al.

Author: Net Nikokinos
Country: Haiti
Language: English (Spanish)
Genre: Health and Food
Published (Last): 15 August 2004
Pages: 215
PDF File Size: 3.53 Mb
ePub File Size: 19.95 Mb
ISBN: 586-7-54604-234-4
Downloads: 42778
Price: Free* [*Free Regsitration Required]
Uploader: Zusar

This means of communication, called ephaptic coupling, results when the electric field produced by one neuron silences its neighbor, instead of sending neurotransmitters across a synapse. Due to the very small electrical fields produced by neurons, mathematical models are often used in order to test a number of manipulations. It was found that rhythmic electrical discharge associated with fetal neurons in the rat spinal cord and medulla was still sustained.

Ephaptic coupling in cortical neurons

Does ephaptic coupling happen when we eat and drink? Possible Contribution of Astroglial Magnetic Fields? In the simpler case of adjacent fibers that experience simultaneous stimulation the impulse is slowed because both fibers are limited to exchange ions solely with the interstitial fluid increasing the resistance of the nerve.

Citations Publications citing this paper. In particular, we find that ephaptic coupling strength depends both on the field strength as measured at the cell body as well as the spike-history of neurons. A number of studies have shown how inhibition among neurons in the olfactory system work to fine tune integration of signals in response to odor.

The electrochemical processes that underlie neural function manifest themselves in ceaseless spatial and temporal fluctuations in the extracellular electric field.

Neurons Talk Without Synapses | The Scientist Magazine®

In Arvanitaki [5] explored the same topic and proposed the usage of the term “ephapse” from the Greek ephapsis and meaning “to touch” to describe this phenomenon and distinguish it from synaptic transmission.

Depending on the epgaptic and identity of the neurons, various mechanisms have been found to underlie ephaptic inhibition. It may refer to the coupling of adjacent touching nerve fibers caused by the exchange of ions between the cells, or it may refer to coupling of nerve fibers as a result of local electric fields.


To register or login click here. When Su exposed flies to a steady stream of methyl hexanoate, the A neuron fired continuously. Suppression of epileptiform activity by high frequency sinusoidal fields in rat hippocampal slices.

Although this ephaptic coupling coupllng been seen in the cerebellum of rats, within a group of neurons called Purkinje cellsno one knew what neuronss it had. The relationship between local field potentials LFPs and the electromagnetic fields that give rise to them Colin G. While the idea of non-synaptic interactions between neurons has existed since the 19th century, there has historically been a lot of skepticism in the field corticxl neuroscience. Neurons in the olfactory system are unmyelinated and densely packed and thus the often small effects of ephaptic coupling are more easily seen.

Similarly, the currents that caused repolarization of the active nerve caused slight depolarization in the resting fiber. Retrieved from ” https: We hypothesize the functional role of such coupling in various brain states, for example, during visual processing Cogtical, Encyclopedia for Computational Neuroscience, Springer, Durand The Journal of physiology This inhibition has been shown to occur from changes in electrical potentials alone.

The simulations allow us to examine ephaptic coupling and dissociate between the feedforward from membrane currents to LFP and feedback from LFPs to membrane voltage via ephapic coupling effect in unprecedented detail.

References Publications referenced by this paper. We stimulated in rat somatosensory cortical slices a variety of layer 5 neural types and recorded inside and outside their cell bodies while cortiacl silencing synaptic transmission. Simultaneous action potential firing caused interference and resulted in decreased conduction velocitywhile slightly offset stimulation resulted in synchronization of the two impulses.

Ephaotic example, the currents that caused the depolarization excitation of the active nerve caused a cotrical hyperpolarization depression of the adjacent resting fiber.

Ephaptic coupling

Neurophysiology Cellular neuroscience Signal transduction. Login Required This action requires you to be registered codtical Frontiers and logged in.

From This Paper Topics from this paper. Su found the same interactions in four other types of sensilla in the fruit fly, as well as one in the malarial mosquito Anopheles gambiae. We address this question through detailed large-scale simulations from thousands of biophysically realistic and interconnected neurons Reimann, Anastassiou et al, Neuron, emulating circuit activity.


The firing of these basket cells, which occurs more rapidly than in the Purkinje cells, draws current across the Purkinje cell and generates a passive hyperpolarizing potential which inhibits the activity of the Purkinje cell.

Katz and Schmitt also observed that stimulation of both nerves could cause interference effects. When both chemicals were in the air, the flies were no longer repelled by carbon dioxide. In the antennae of Drosophila melanogasterolfactory neurons are bundled into fluid-filled hairs called sensilla. Large-scale calcium waves traveling through astrocytic couling in vivo. How do such effects manifest themselves in vivo? One study tested the effects of ephaptic coupling by using both neurotransmitter anatagonists to block chemical synapses and gap junction blockers to block electrical synapses.

Ephaptic coupling has also been found to play an important role in inhibition of neighboring neurons. The electrical conduction system of the heart has been robustly established.

However, newer research has been challenging some of the previously accepted models. This coupling may effectively synchronize neurons into periods of enhanced excitability or depression and allow for specific patterns of action potential timing often referred to as spike timing.

Ephaptic coupling – Wikipedia

When one fires, it creates an electric field that directly changes the flow of ions through the other and shuts down its electrical activity. Ephaptic coupling in cortical neurons. Please enable Javascript in your browser settings in order to see all the content on this page.

Fundamentals of transcranial electric and magnetic stimulation dose: This effect has been demonstrated and modeled in a variety of cases. Their vinegar neuron, while severed from the brain, could still inhibit its neighboring carbon dioxide neuron. New Cortical Neuron Types.