due to the massive amount of neurons in the brain, how is it possible that electrical signals don’t crosspost (don’t mind if I do) from one axon to another?

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Electrical signals are transmitted in the most superficial outer layer of the axon (along the myelin sheath) or, at least, that’s what I’ve been told at school.

Is this (if any, ofc) one of the reasons why human thinking is so complex?

In: Biology
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They sort of do.

A neurone that transmits an electrical signal increase the chance that other neurones will fire.

And yeah, that’s another reason as to why we’re really complex.

An extra tidbit, neurones are not binary; 1 or 0. They are are more like **potentials**. So, when a neurone fires it does not mean that other neurones will fire, it only **increases the chance that other neurones fire.**

That’s probably why humans are so freaking diverse. Aa 0.004 difference in the time it took for a neurone to fire can make a **very big difference** in the result of an action.

The distance between axons of different neurons is a lot bigger than the distance between individual jumps between the Ranvier nodes of the axon, the gaps in the myelin sheath. I doubt there could really be any kind of arcing across neurons given that.

Additionally, axons aren’t wires: they carry electrical charge, but not in the way that computer chips do, and so they can’t tally transmit across the space between axons.

The myelin sheath is just an insulator. The charged ions diffuse inside the cell which is surrounded by the myelin sheath. At the nodes of Ranvier (areas of axon not covered) charges get a refresh with more ions so the charge can continue down the axon.

At the terminal end of the axon is where neurotransmitters are released to be noticed by dendrites of a neighboring neuron. The charge has no where to “leak” from since it’s not in the form we think of. It’s just an ion imbalance which gives the charge.

The charge is just the physical push for the neuron to release neurotransmitters into the post synaptic cleft. All communication between differing nerve cells is mediated by neurotransmitters.

The action potential of the neuron has to be sufficient to get the neurotransmitters to dump. When they do, it’s only in the synaptic cleft designated by that one axon for the next. Or so I recall. But damn it’s been a whole minute since college.

TIL Neurons are spelled differently in . . .UK?

Yes, it is believed that the signals from one neuron’s axon may influence other neurons. It is known as ephaptic coupling. However, this type of “crosstalk” does not mean that action potentials can jump between axons, it is a relatively weak signal. It is thought that this type of interaction might be able to slightly shift the timing of a neuron’s firing (as opposed to being strong enough to make it fire when it otherwise wouldn’t have).

As an aside, you mentioned something about action potentials traveling along the myelin, which is not quite correct. Action potentials are generated/renewed on the neuron’s surface (only on the unmyelinated parts, which is why myelinated neurons have regular gaps in the myelin), then propagated along the inside of the axon.

Yes, it is believed that the signals from one neuron’s axon may influence other neurons. It is known as ephaptic coupling. However, this type of “crosstalk” does not mean that action potentials can jump between axons, it is a relatively weak signal. It is thought that this type of interaction might be able to slightly shift the timing of a neuron’s firing (as opposed to being strong enough to make it fire when it otherwise wouldn’t have).

As an aside, you mentioned something about action potentials traveling along the myelin, which is not quite correct. Action potentials are generated/renewed on the neuron’s surface (only on the unmyelinated parts, which is why myelinated neurons have regular gaps in the myelin), then propagated along the inside of the axon.

Yes, it is believed that the signals from one neuron’s axon may influence other neurons. It is known as ephaptic coupling. However, this type of “crosstalk” does not mean that action potentials can jump between axons, it is a relatively weak signal. It is thought that this type of interaction might be able to slightly shift the timing of a neuron’s firing (as opposed to being strong enough to make it fire when it otherwise wouldn’t have).

As an aside, you mentioned something about action potentials traveling along the myelin, which is not quite correct. Action potentials are generated/renewed on the neuron’s surface (only on the unmyelinated parts, which is why myelinated neurons have regular gaps in the myelin), then propagated along the inside of the axon.

Yes, it is believed that the signals from one neuron’s axon may influence other neurons. It is known as ephaptic coupling. However, this type of “crosstalk” does not mean that action potentials can jump between axons, it is a relatively weak signal. It is thought that this type of interaction might be able to slightly shift the timing of a neuron’s firing (as opposed to being strong enough to make it fire when it otherwise wouldn’t have).

As an aside, you mentioned something about action potentials traveling along the myelin, which is not quite correct. Action potentials are generated/renewed on the neuron’s surface (only on the unmyelinated parts, which is why myelinated neurons have regular gaps in the myelin), then propagated along the inside of the axon.

In addition to myelin insulation, your brain also gets used to some neurons firing more commonly overtime than others, and in a way starts to make assumptions. One of the most common examples is during a heart attack. We don’t really feel our heart that often, so when it does start sending signals to the brain, it often feels like a left arm or shoulder, and maybe some jaw and neck pain. Because those are parts that commonly send info to your brain, your brain assumes that’s how the info should be interpreted.