Reference request: source that calls irradiation a "law"?

mc · #1 (**permalink**) 11-06-2009, 12:37 PM

I know PTTP talks about sherrington's laws - one of which is irradiation.
but i can only find a source for two things referred to as laws in the sherrington cannon.

Sherrington indeed critiqued a contemporary's use of the term "laws" around irradiation (cuz according to sherrington, Pflüger got it ass backwards, but he doesn't say that what he's doing are the "right" laws - really nice review of sherrington's work here.)

It's in his 1906 big book The Integrative Action of the Nervous System he talks about nerve reflexes and irradiation, but he doesn't as far as i can tell, name anything in the discussion a law.

The two laws i know of associated with Charles Sherrington are

1) Every dorsal spinal nerve root supplies a particular area of the skin, the dermatome, which is, however, invaded above and below by fibres from the adjacent spinal segments.

also expressed as "Every posterior spinal nerve root supplies a particular area of the skin, with a certain overlap of adjacent dermatomes."

2) AKA The law of reciprocal innervation. When contraction of a muscle is stimulated, there is a simultaneous inhibition of its antagonist. It is essential for coordinated movement.

A dermatome by the way is an area of the skin supplied by a single spinal nerve, and great to help identify damage to the spine. Here's a neat image of dematome mappings.

Indeed, i've no idea if Sherrington called these "laws" himself or if others did, but these are the only two consistently associated with his name by neurology sources.

Neither of these laws relate to nerve/muscle reflex irradiation, though what Pavel calls such a law certainly maps to Sherrington's descriptions of neural irradiation Integrative Action of the Neural System. Pavel writes:

Quote:

the Law of Irradiation. It states that a muscle working hard recruits the neighboring muscles, and if they are already a part of the action, it amplifies their strength! Not by cheating, as some complement their barbell curls with a back swing, but by cheering. The neural impulses emitted by the contracting muscle reach other muscles and turn them on as electric current starts a motor.

Sherrington also points out that time is a factor: you have to wait some seconds to get this coordinated effort turned on with medium muscular effort.

So irradiation is a nice description, but i can't find any place where it's expressed as The Law Of...

Though, if Pavel invented this monicer, it's interesting to see its modern and unattributed appearance in the writings of others. Just check the net for "law of irradiation" when not something by pavel and see if anyone sites PTTP or any other text for backup.

Anyway, if anyone has a text book out there or other scholarly source that calls "irradiation" a law, please shout - or if you learn who used the term "law" - i think sherrington did call no. 2 "the law of reciprocal innervation" (tho it's about reciprocal inhibition)

Thanks

ever questing

mc

ddn · #2 (**permalink**) 11-06-2009, 02:58 PM

mc: does this help?

A text-book of physiology - Google Books

"law of irradiation" -pavel - Google Search turns up quite a bit, though I don't pretend to know what to look for to answer your query.

Rambodoc · #3 (**permalink**) 11-07-2009, 01:32 AM

I read about Sherrington's Law of Reciprocal Innervation way back when in med school. I aced physio, so I know!

TommyP · #4 (**permalink**) 11-07-2009, 05:24 AM

I have read some references to this in books on proprioceptive neuromuscular facilitation and Voss and Knott are authors that first put this stuff into writing I think. The concept of irradiation is part of the theorectical framework for PNF. Check out Institute of Physical Art, continuing education courses and go to the required readings section and there are some free PDF articles on there that might help you, its been a little while since I have read this material but this might help you get some more answers. Hope this helps

mike barkess uk · #5 (**permalink**) 11-07-2009, 06:40 AM

mc,

I've had a quick look through Alter's 'Science of Flexibility', 3rd Ed, 2004, where he makes reference to 'irridation' within a discussion of PNF (p.165). However, I can't find reference to a 'law' within that particular text.

FYI, Alter cites

Alder, Beckers, and Buck, 'PNF in practice: An illustrated guide', 2nd Ed, 2000

Holt, 'Scientific stretching for sports (3-s)', n.d.

and Surburg, 'Neuromuscular facilitation techniques in sports medicine' in The Physician and Sportsmedicine, 18(1), 114-127, 1981

as his sources.

Mike.

mc · #6 (**permalink**) 11-07-2009, 09:49 AM

Quote:

Originally Posted by mike barkess uk

mc,

I've had a quick look through Alter's 'Science of Flexibility', 3rd Ed, 2004, where he makes reference to 'irridation' within a discussion of PNF (p.165). However, I can't find reference to a 'law' within that particular text.

FYI, Alter cites

Alder, Beckers, and Buck, 'PNF in practice: An illustrated guide', 2nd Ed, 2000

Holt, 'Scientific stretching for sports (3-s)', n.d.

and Surburg, 'Neuromuscular facilitation techniques in sports medicine' in The Physician and Sportsmedicine, 18(1), 114-127, 1981

as his sources.

Mike.

exactly so.

i've gone through a few of these, and the two neurophysio, neuromechanics texts i have only talk about irradiation the concept.

#ddn - thanks
that ref in 1905 isn't to Sherrington, but to Ott (full text) and is very different than Sherrington's in 1906 including his critique of Pflüger so called "law of irradiation"
but thank you very much for trying on that.

Thanks everyone for giving this a go.

It seems, humbly suggesting, that attributing "law" to sherrinton's version of irradiation, which is what we still use today, is a bit of a misnomer with respect to the literature perhaps.

best,

mc