Am I coming or going...

[Catharsis]

Hi...

 

In reference to “Somatic” nervous system.....

 

I understand it’s use with the Motor division (efferent). Voluntary, innervates skeletal muscle.... No problem..

 

But how can “somatic” be voluntary with the Sensory division (afferent)? Receives sensory information from skin, fascia, joints, skeletal muscle.

 

Am I missing something here?

 

Any opinions, suggestions and comments will be appreciated

 

Thank you in advance...

[Glider]

Hi...

 

In reference to “Somatic” nervous system.....

 

I understand it’s use with the Motor division (efferent). Voluntary, innervates skeletal muscle.... No problem..

 

But how can “somatic” be voluntary with the Sensory division (afferent)? Receives sensory information from skin, fascia, joints, skeletal muscle.

 

Am I missing something here?

 

Any opinions, suggestions and comments will be appreciated

 

Thank you in advance...

You're welcome, in advance.

 

Yes, you are missing something, but not much. The term 'voluntary' as used for the somatic nervous system (SNS) is to differentiate it from the autonomic nervous system, not to differentiate the efferent division of the SNS from the afferent divisions of the SNS.

 

A review of the main divisions of the nervours system:

 

First division: Central Nervous System (CNS) Vs Peripheral Nervous System (PNS).

 

The CNS includes all that which is encased by bone, i.e. the brain and spinal chord. The PNS is everything outside of that.

 

There are other differences, e.g. collections of nerve cell bodies in the CNS are known as nuclei, but outside of the CNS they are known as ganglia. But essentially, encased in bone (skull or vertebra) = CNS, outside of that = PNS.

 

Second division: Somatic Nervous System (SNS) Vs Autonomic Nervous System (ANS).

 

Third division 1:The SNS is divided into the Afferent and Efferent divisions. Efferent (motor) nerves leave the spinal cord via the ventral horn and afferent (sensory) nerves enter the spine vial the dorsal horn.

 

Third division 2:The ANS is divided into the sympathetic and parasympathetic divisions. The sympathetic division is responsible for activation and preparation to expend energy (fight or flight). The parasympathetic is responsible for 'stand-down'; conservation of energy. These two divisions exist in tonic balance with one another. These divisions innervate things like smooth muscle (e.g. GI tract), glands, kidneys, bladder, veins (vasodilation and constriction), pupils, sweat glands etc.. All these are outside of voluntary control

 

The somatic division of the PNS is known as 'voluntary' simply to differentiate it from the autonomic division of the PNS which, eponymously, is autonomic and outside of voluntary control.

[Catharsis]

So for all “intensive” purposes - from the hallway - the boys room is separate from the girls room (for when the parents visit) and that’s it (ones voluntary and the other isn’t). But if you wanna split hairs and get all scientific about it - you will find that the boy’s room has a “girls” room also (inside).

 

My dear Watson - I think I’ve got it....

 

I tell ya though - some of the explanations in some textbooks should be punishable by law....

[Glider]

So for all “intensive” purposes - from the hallway - the boys room is separate from the girls room (for when the parents visit) and that’s it (ones voluntary and the other isn’t). But if you wanna split hairs and get all scientific about it - you will find that the boy’s room has a “girls” room also (inside).

 

My dear Watson - I think I’ve got it....

I'm not sure I understand your analogy. Each division of the nervous system is separate from the other divisions. It's just a question of remembering these divisions. Things make sense if you can do that. I should have mentioned that the second division (Somatic NS & ANS) are both divisions of the Peripheral Nervous System (PNS).

 

PS, You mean 'for all intents and purposes'.

 

I tell ya though - some of the explanations in some textbooks should be punishable by law....

True. Edited October 1, 2008 by Glider

[CRANC]

You're welcome, in advance.

 

Yes, you are missing something, but not much. The term 'voluntary' as used for the somatic nervous system (SNS) is to differentiate it from the autonomic nervous system, not to differentiate the efferent division of the SNS from the afferent divisions of the SNS.

 

A review of the main divisions of the nervours system:

 

First division: Central Nervous System (CNS) Vs Peripheral Nervous System (PNS).

 

The CNS includes all that which is encased by bone, i.e. the brain and spinal chord. The PNS is everything outside of that.

 

There are other differences, e.g. collections of nerve cell bodies in the CNS are known as nuclei, but outside of the CNS they are known as ganglia. But essentially, encased in bone (skull or vertebra) = CNS, outside of that = PNS.

 

Second division: Somatic Nervous System (SNS) Vs Autonomic Nervous System (ANS).

 

Third division 1:The SNS is divided into the Afferent and Efferent divisions. Efferent (motor) nerves leave the spinal cord via the ventral horn and afferent (sensory) nerves enter the spine vial the dorsal horn.

 

Third division 2:The ANS is divided into the sympathetic and parasympathetic divisions. The sympathetic division is responsible for activation and preparation to expend energy (fight or flight). The parasympathetic is responsible for 'stand-down'; conservation of energy. These two divisions exist in tonic balance with one another. These divisions innervate things like smooth muscle (e.g. GI tract), glands, kidneys, bladder, veins (vasodilation and constriction), pupils, sweat glands etc.. All these are outside of voluntary control

 

The somatic division of the PNS is known as 'voluntary' simply to differentiate it from the autonomic division of the PNS which, eponymously, is autonomic and outside of voluntary control.

 

This dood wins.