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PowerStacheOfTheYear t1_jd90uqn wrote

Reply to comment by johnsadventure in (Biology) How far down your spine can you break before respiratory impairment? by Anomaly-Friend

The heart is actually not reliant on the brain, as it has its own internal pacemaker. Signals from the nervous system can speed it up or slow it down in response to various factors, but without any signal it will just continue to beat on its own at a very steady rhythm and rate. Around 60 bpm if I remember correctly.

As far as surviving after the drop, I have to wonder what that yank of the rope does to your brainstem. If the pull on the spinal cord causes significant tearing and damage in the brainstem, your entire brain would essentially just "turn off". The brainstem is responsible for regulating your brain activity as a whole. Without the activating signals it sends out, the rest of your brain basically shuts down.

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Jfrog1 t1_jd9kz6i wrote

um, no, the brain does control the heart, not sure who told you that, but they lied to you.

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garlicgoon3322 t1_jd9nzu2 wrote

The heart creates it's own electrical pulses.

The heart will still beat when disconnected from the body.

You are speaking confidently about something you don't thoroughly understand

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[deleted] t1_jd9ps3d wrote

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GroinShotz t1_jd9uj6s wrote

As long as it was fed oxygen... Yes. I think that's where you're being confused... The brain does play a role in the heart pumping... by keeping the other organs supplying the heart with what it needs.

It's why people that are "brain dead" can be kept "alive" for a while, with a machine that breathes for them. The brains not sending the signals to the lungs to get oxygen in the blood stream to supply the heart with the energy it needs to beat.

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Brrdock t1_jd9vuiz wrote

You don't? Why?

I'm sure you can go on liveleak to find some decapitation video, but from seeing a cow get slaughtered by decapitation myself, the heart definitely keeps pumping blood for a good while

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Jfrog1 t1_jdaconl wrote

You don't understand the concept of a sodium potassium pump in cellular biology?

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Tiny_Rat t1_jdadkhz wrote

What does that have to do with the heart requiring brain activity to function?

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[deleted] t1_jdafa3g wrote

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[deleted] t1_jdanaxh wrote

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PowerStacheOfTheYear t1_jd9mtxu wrote

The nervous system can control the heart, but the heart isn't dependent on input from the nervous system to beat. Without any input from the nervous system, the heart will continue to beat on its own, it will just lose the vast majority of its ability to adjust based on the body's needs.

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Jfrog1 t1_jd9nyo6 wrote

the heart is controlled by the autonomic nervous system, which is a subset of the hypothalamus and medulla oblongata, ie (brain). This is not really a debate, your completely wrong, and I am 100 percent right.

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PowerStacheOfTheYear t1_jd9q2zj wrote

Okay, I will be sure to reach out to my medical school and let them know that modern medicine completely misunderstands the function of cardiac pacemaker cells and the sinoatrial node. They should also check on all the people walking with dysautonomia. I'm sure they will be surprised that their hearts actually haven't been beating this whole time.

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Jfrog1 t1_jd9qfr9 wrote

what do you think controls the AV node, the SA node, and the Bundle of hiss?? the heart controls itself, or its impulses come from the ANS, which is a sub branch of the CNS, which is the brain and the spinal cord.

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Astralwinks t1_jdafvjt wrote

Are you suggesting something afib is actually neurological in origin?

Call JAMA, The Lancet, NEJM! They have to know!

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Minus-Celsius t1_jdcs256 wrote

Wait you googled SA node and you still think you're not wrong?

Damn, dude.

The brain controls the SA node, but the SA node can function without the brain. There's also a ventricular pacemaker. There's backups to the backups. The heart is an important organ.

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tonypconway t1_jd9sumq wrote

You're confidently incorrect. I'm only vaguely familiar with this topic as my dad had heart surgery last year, and I have a tetraplegic friend who has explained some of it to me. But it only took about five minutes of fudging about on Wikipedia to find a detailed explanation of how the heart generates its own impulses: https://en.wikipedia.org/wiki/Sinoatrial_node?wprov=sfla1

The brain and other systems can influence the rate, but they aren't the primary driver. This is why people get arrhythmia - different systems sending contradictory signals.

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IthinkIllthink t1_jd9p9r3 wrote

The heart has “pacemaker cells” that make it beat/contract without any nerve input. Look up pacemaker cells.

The ANS speeds up or slows down the heart rate.

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Jfrog1 t1_jd9q4za wrote

if you put a bullet through the medulla oblongata/brain stem, the heart stops, this is simple stuff, does it happen immediately, no, as electrical impulses are still working, but your concept that the heart controls itself is so basic and unfounded, I am amazed you made it through high school biology

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IthinkIllthink t1_jd9qty1 wrote

Perhaps that’s from the trauma of the gun shot.

Look at a video of the transport or removal of a human heart for a heart transplant. It is beating without any nerve input.

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ilikeyourjacket t1_jdcqxv8 wrote

You’re right the ANS can influence heart rate but the heart itself has an intrinsic rate. The SA node has an intrinsic rate between 60-100bpm. The AV nice has an intrinsic rate of about 40-60bpm. The ventricles have an intrinsic rate of about 30bpm. That’s why in complete heart block often the heart rate is about 30bpm as that’s the default rate of the ventricles when signals from the SA or AV node are blocked.

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