Muscular functions

I would like to know too, just curious

Within your muscle spindles, there are afferent sensory neurons, Ia/II, which send a signal to your spine when a force is placed on your muscles like filling a cup with water, which creates this downward force. To compensate, without thinking efferent motor neurons leaving your spine determine levels of contraction. Gamma Motor neurons set the gain on your muscles, while alpha motor neurons create excitatory connections with the muscle that you want to contract, while creating inhibitory connections with the opposing muscle, such as the biceps/triceps. On your muscle tendons, Golgi organs like the 1b Neuron limits the amount of contraction to prevent injury.

Was this kind of what you were looking for? I'm happy to answer any questions.

>>7960773
By the way, this all kind of happens at the inter neuronal junctions within the spine, it sends information to your brain after the signaling pathways have already been activated.

>>7960773
I've attached a picture, I know it's hard to really tell what's going on but these are the diagrams I drew myself in my neuroscience of motor control lectures.

File: image.jpg (2MB, 3264x2448px) Image search: [Google]

2MB, 3264x2448px

>>7960780
Shit totally forgot picture, my bad.

>>7960773
>>7960776
That's very helpful, thank you!
So, to force a muscle to stop in a specific position from outside input, the electrical signals and functions of Gamma and Alpha neurons, and Golgi organs would have to be emulated, or would it be easier to stimulate those specific types of neurons/organs in specific ways from the outside source?

>>7960794
In my own limited understanding of how our nervous system "stops" muscles, you would want to manage the outpost of the gamma neurons, the 1b neurons (Golgi organs), and the inhibitory alpha neurons, which use acetylcholine as their neurotransmitter. Essentially, each muscle has a partner muscle that it contracts/extends in conjunction with, and they regulate each other. I think that line of thinking is on the right track though.

This is all for passive muscular movements, when you plan movements and involve the brain it all gets way way more complicated.

>>7960806
Well here's my vision for the utility:
In an extension to the HTC Vive headset, or Oculus or whatever, it could probably be made cross platform, this device would use the position of the tracked controllers in conjunction with collision meshes to counteract any force being applied by a muscle when that force and subsequently the controller are colliding with the virtual mesh. My thoughts are that this can provide an illusory sense of physicality to the virtual objects, and when used with physics engines and more complex calculation, could be used as a way to feel the interaction, i.e. more or less resistance in your arm muscles based on the force calculations between collision meshes.
So to do this, it sounds like the only way would be to use acetylcholine or something with similar structure to transmit the simulated neurological signals that are induced when the vive detects a collision, which means some kind of invasive procedure, which means fuck.
Thank you for all your help.

>>7960818
Well you could cause the release of acetylcholine through a depolarization of the neuron via an electric signal.

>>7960832
Where would that electric signal have to be targeted, and how would you use that to control the acetylcholine output, and in what way would that affect the muscles?

OP, are you thinking of transcutaneous (across the skin) muscular stimulation, like in the 'exercise your fat away without exercising' bands? They are pretty primitive but might get you somewhere, and without sticking electrodes in people.

>>7960773
>>Gamma Motor neurons set the gain on your muscles,
by gain you mean a proportional input output relation? Is this dynamically adjustable?

>>7961334
Not the anon who actually remembers some physiology, but what I do recall is yes, gamma activity is mediated by the pons and medulla's (brainstem) 'reticular formation' which takes input from many sources to set a 'tone' or gain as anon put it. Adjustable by stress hormones vs. relaxation, emotional state, etc; the 'arousal level', but basically it has connections in and out to just about everything in the brain.

Try this
https://kin450-neurophysiology.wikispaces.com/Muscle+Spindle

>>7960773
Nerd