Daichi Katase

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where the muscle starts out? Like for your biceps start at the shoulders so they will be the afferent. Or do i have it backwards? Maybe it is efferent?

Please completly ignore this reply.
 
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Efferent & afferent refer to neurons..... sensory neurons are afferent; motor neurons are efferent. Still clueless about muscle afferents. Do they send impulses to the brain? "Muscle" must mean PNS.... are the cell bodies in the spinal cord? Someone..?
 

N-toxicologist

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Muscle afferents are your spindle fibers and golgi tendon organs(?). They are the fibers that send info to your brain about muscle length and tension, respectively, I believe.
 

laya533

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We dont have such a term. Afferents are the nerves that carry signal to the brain. Moreover, this afferent signal could be from a muscle.
 

jeg5q

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I agree with one of the earlier posts. Muscle afferents in my experience refers to the axons of neurons responsible for registering the length of stretch (chain muscle spindles) or the rate of stretch (ball?? muscle spindles). This sensory info is then used to adjust the sensitivity of the muscle spindles themselves via gamma motorneuron efferents which travel back out to the muscles. I don't know if this helps or confuses, there is a lot of stuff going on here that is pretty complicated. If you really want to check this out in depth try to find a good physiology text and read the chapter on muscle phys. Good luck in April.
 

nicholonious

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I doubt you guys need to know much on this topic concerning the MCAT. Just that it is a sensory neuron, sends signals from the environment to the brain (via spinal cord from muscle) and then is sent back to perform an action by motor neuron. It might be handy to know which one travels through the dorsal root ganglia and ventral horn.

A good way of remembering the two is that afferent resembles "affected" and efferent resembles "effected" or to "effect" something.


Hope it helps.
 

humuhumu

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Muscle afferents are nerves that convey stretch information from muscle spindles to the spinal cord. Muscle spindles are essentially tiny muscle fibers, interspersed in parallel among regular muscle fibers, that provide a kind of proprioception, telling the CNS how long your muscles are and how rapidly they are changing in length. You'll learn all of this in medical school; I'm not sure it's fair game for the MCAT.

"Afferent" means that the information is Approaching the CNS; "efferent" means that the information is Exiting the CNS.
 

fozziewan

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Basically, Afferent neurons carry Sensory information from the periphery to the CNS where it is processed.
Efferent neurons will carry information from the CNS to the periphery. Specifically to the muscles. Thats as basic as can be without going into the golgi tendons, gamma efferents, alpha motor neurons, a-delta fibers, interneurons, etc...
Anyways, I hope this helps. Feel free to PM me with any other questions. :D
 

cfdavid

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juniper456 said:
just think "SAME": Sensory=Afferent, Motor=Efferent
Hey, you stole that from EK! So, I will too.

Think SAME DAVE; Sensory=Afferent Motor=Efferent
Dorsal=Afferent Ventral=Efferent

Dorsal/Ventral refering to the location of the ganglia entering and exiting the spine.
 

fozziewan

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Nice, I guess I should look over my EK stuff in addition to my TPR stuff. I just thought I'd go into a quick lil blurb that I learned in A&P.