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Medical Terminology : motor efferents vs lower motor neurones

In motor neurone disease, lower (and often upper) motor neurones deteriorate and this causes a loss of VOLUNTARY control of muscles.

Am I correct in saying that motor efferents are STILL intact for autonomic efferents? Surely these would not also be called "lower motor neurones"? Is there a way to establish what motor neurones you are actually referring to in conversation? Would I call the AUTONOMIC and VOLUNTARY lower motor neurones for example, or does the name "lower motor neurone" imply I am referring to voluntarily controlled motor neurones?

Thank you.
Reply 1
Original post by medicmonk
In motor neurone disease, lower (and often upper) motor neurones deteriorate and this causes a loss of VOLUNTARY control of muscles.

Am I correct in saying that motor efferents are STILL intact for autonomic efferents? Surely these would not also be called "lower motor neurones"? Is there a way to establish what motor neurones you are actually referring to in conversation? Would I call the AUTONOMIC and VOLUNTARY lower motor neurones for example, or does the name "lower motor neurone" imply I am referring to voluntarily controlled motor neurones?

Thank you.

Lower motor neurones can be subdivided into general visceral motor neurones (i.e. autonomic motor neurones) and somatic motor neurones (those that control voluntary muscles), as well as special visceral motor neurones - but these are less relevant here.

So yes, technically lower motor neurones includes autonomic and somatic motor neurones, but in practice, LMN usually refers to somatic motor neurones.
Reply 2
Original post by Jpw1097
Lower motor neurones can be subdivided into general visceral motor neurones (i.e. autonomic motor neurones) and somatic motor neurones (those that control voluntary muscles), as well as special visceral motor neurones - but these are less relevant here.

So yes, technically lower motor neurones includes autonomic and somatic motor neurones, but in practice, LMN usually refers to somatic motor neurones.

thank you !

GSEs are responsible for gland secretions. But are they also responsible involuntary MUSCLE contractions ? Eg contraction of the internal anal sphincter or of the muscles involved in the ejaculation ?

Thanks . :smile:
Reply 3
Original post by medicmonk
thank you !

GSEs are responsible for gland secretions. But are they also responsible involuntary MUSCLE contractions ? Eg contraction of the internal anal sphincter or of the muscles involved in the ejaculation ?

Thanks . :smile:

General visceral efferents are responsible for gland secretion, not GSE fibres. General visceral efferents are also responsible for innervating involuntary muscles (smooth muscle and cardiac muscle), including the internal anal sphincter and muscles involved in ejaculation.

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