How do people paralysed from the neck down still retain the ability to breathe, pump blood, metabolise food etc., even though their muscles are paralysed?

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How do people paralysed from the neck down still retain the ability to breathe, pump blood, metabolise food etc., even though their muscles are paralysed?

In: Biology
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>It depends on the level of paralysis. The diaphragm is innervated by the ventral roots of the cervical roots from C3/C4/C5, so lesions at or above those levels may indeed result in loss of diaphragm function, and thus require mechanical ventilators to breathe.

>The heart functions fairly autonomously (since its contractions are mediated by the SA node), and is thus able to beat independent of spinal influences. However, there are a number of parasympathetic and sympathetic inputs to the heartbeat, such that damage to the vagus nerve (unlikely in a purely spinal lesion, since the vagus nerve is a cranial nerve) may result in tachycardia, and damage to the sympathetic ganglia may result in inability to modulate inotropy.

>Digestion is similarly largely governed by neurons of the enteric nervous system, which function fairly independently of higher-order inputs. There is some parasympathetic and sympathetic signal to the gut, which may indeed affect digestion, but my understanding is that those factors aren’t as important as the native enteric nervous system.

https://www.reddit.com/r/askscience/comments/vju09/how_can_quadriplegics_breathe/c5547so/

Only some control of that stuff goes through the spine, you also have the vagus nerve that controls a lot of it. Then the heart and digestion can function with no connections to anything at a basic level.

breathing is the hardest, and paralyzed people can require breathing assistance. But it takes a pretty bad injury and is the type you are mostly likely to die from immediately, it absolutely happens but there is some amount of selection bias where the people that make it to live as a paralyzed person got injuries that are somewhat survivable.

If you are paralyzed the reason tends to be damage to the spinal code.

In it the nerves that control your skeletal muscles, that you use to move around, are located. This is the peripheral nervous system (PNS)

But you have other nerves too that do not pass through the spinal cord. The Autonomic nervous system (ANS) where nerves that control breathing and other internal organs.
https://en.wikipedia.org/wiki/Autonomic_nervous_system#/media/File:1503_Connections_of_the_Parasympathetic_Nervous_System.jpg

If your spinal cord is broken to high up where a nerve in this system exist it the damage will kill you. This is the type of damage that kills you if you are hanged.

Your heart and intestine system do not need stimuli from the brain to work, the heart can beat by itself. The brain needs to control breathing and if those nerves are damage you die.

it’s simple really , those muscles aren’t paralyzed(completely), that’s as simple as that,
some people do die from complete paralysis though or rather they die from asphyxiation due to them not breathing as a side effect of that paralysis