<p>Neuronal membranes act as capacitors: there is a charge separation between inside and outside due to the (relatively) impermeable membrane to charged ions. The voltage of a neuron is a charge separated across the membrane. However, the electric field <em>outside</em> a capacitor is <strong>negligible</strong>. In many physics problems it's treated as simply zero. See some Q&amp;A on Physics.SE:</p>
<p><a href="https://physics.stackexchange.com/questions/12309/electric-field-outside-a-capacitor">https://physics.stackexchange.com/questions/12309/electric-field-outside-a-capacitor</a></p>
<p><a href="https://physics.stackexchange.com/questions/274155/electric-field-outside-a-infinitely-long-capacitor">https://physics.stackexchange.com/questions/274155/electric-field-outside-a-infinitely-long-capacitor</a></p>
<p><a href="https://physics.stackexchange.com/questions/271127/what-is-the-electric-field-and-potential-outside-a-spherical-capacitor">https://physics.stackexchange.com/questions/271127/what-is-the-electric-field-and-potential-outside-a-spherical-capacitor</a></p>
<p>Because of this, there isn't any good reason from the physics of a neuron that you'd expect a neuron to be affected by the electric field of its neighbor. The field itself is tiny, and changes in the field are tinier still.</p>
<p>Some neurons communicate directly to each other through <a href="https://en.wikipedia.org/wiki/Gap_junction" rel="nofollow noreferrer">gap junctions</a>, but that's because these connections cause a gap in the membrane that joins the inside space of one cell with the inside of another, allowing ions to flow freely between them. It's also possible for neighboring neurons to be influenced by changes in extracellular ion concentrations, but this really only happens in bulk circumstances such as <a href="https://journals.physiology.org/doi/abs/10.1152/jn.1995.73.5.2107" rel="nofollow noreferrer">cortical spreading depression</a>, ischemia, or seizure, rather than normal neuronal communication.</p>

CC BY-SA 4.0
2022-01-08T05:58:45.093Z
Thanks! Yes, but even if the outer electric activity in the axon is teeny and small-scale, why should it be considered as neglectable? They are still there, aren't they? And could it be that a stronger sum of these electronic activities in larger neural columns enlargen the communication? All activities in a neuron doesn't imply a synaptic fire. It could be thresholds, but also an activity in itself.... On a global brain scale, we do of course measure these electrics (they are not zero) according to a wide range of different predictive and reactive activities (cognition, motor, sensor... etc).
Leo B Neo
CC BY-SA 4.0
2022-01-08T06:33:51.813Z
@LeoBNeo The voltages measured by, say, EEG are quite small.
Bryan Krause
CC BY-SA 4.0
2022-01-05T16:02:04.320Z
2022-01-05T16:08:14.527Z
2022-01-05T16:08:14.527Z
Bryan Krause
<p>It is believed that neurons communicate through neurotransmitters, released from multiple synapses and flow to the axon of the next neuron. But has it been shown if a single neuron communicate with a single neighbour neuron by its electric field? (not involving the chemical synaptic cleft).</p>

CC BY-SA 4.0
2022-01-05T22:36:40.757Z
The usual signal path is from *axon terminal* to *dendrite*, rather than axon to axon. See page on [synapse](https://en.wikipedia.org/wiki/Synapse).
Michael
CC BY-SA 4.0
2022-01-08T05:16:05.347Z
Yes, of course, thank you, sorry my text was unclear (English prepositions aren't that easy for a non-native speaker).
Leo B Neo
<cognitive-neuroscience><memory><eeg><consciousness><electrophysiology>
Electric communication between single neurons
Leo B Neo
# Electric communication between single neurons

(Asked by: username_0 on 2022-01-05)

It is believed that neurons communicate through neurotransmitters, released from multiple synapses and flow to the axon of the next neuron. But has it been shown if a single neuron communicate with a single neighbour neuron by its electric field? (not involving the chemical synaptic cleft).

**Tags:** cognitive-neuroscience, memory, eeg, consciousness, electrophysiology

> **Comments:**
> **username_1**: The usual signal path is from *axon terminal* to *dendrite*, rather than axon to axon. See page on [synapse](https://en.wikipedia.org/wiki/Synapse).  
> **username_0**: Yes, of course, thank you, sorry my text was unclear (English prepositions aren't that easy for a non-native speaker).  

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## 1 answers

### Answer by username_2 on 2022-01-05. Score: 2

Neuronal membranes act as capacitors: there is a charge separation between inside and outside due to the (relatively) impermeable membrane to charged ions. The voltage of a neuron is a charge separated across the membrane. However, the electric field *outside* a capacitor is **negligible**. In many physics problems it's treated as simply zero. See some Q&A on Physics.SE:

<https://physics.stackexchange.com/questions/12309/electric-field-outside-a-capacitor>

<https://physics.stackexchange.com/questions/274155/electric-field-outside-a-infinitely-long-capacitor>

<https://physics.stackexchange.com/questions/271127/what-is-the-electric-field-and-potential-outside-a-spherical-capacitor>

Because of this, there isn't any good reason from the physics of a neuron that you'd expect a neuron to be affected by the electric field of its neighbor. The field itself is tiny, and changes in the field are tinier still.

Some neurons communicate directly to each other through [gap junctions](https://en.wikipedia.org/wiki/Gap_junction), but that's because these connections cause a gap in the membrane that joins the inside space of one cell with the inside of another, allowing ions to flow freely between them. It's also possible for neighboring neurons to be influenced by changes in extracellular ion concentrations, but this really only happens in bulk circumstances such as [cortical spreading depression](https://journals.physiology.org/doi/abs/10.1152/jn.1995.73.5.2107), ischemia, or seizure, rather than normal neuronal communication.

> **Comments:**
> **username_0**: Thanks! Yes, but even if the outer electric activity in the axon is teeny and small-scale, why should it be considered as neglectable? They are still there, aren't they? And could it be that a stronger sum of these electronic activities in larger neural columns enlargen the communication? All activities in a neuron doesn't imply a synaptic fire. It could be thresholds, but also an activity in itself.... On a global brain scale, we do of course measure these electrics (they are not zero) according to a wide range of different predictive and reactive activities (cognition, motor, sensor... etc).  
> **username_2**: @LeoBNeo The voltages measured by, say, EEG are quite small.  

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