Printer Friendly
Dictionary, Encyclopedia and Thesaurus - The Free Dictionary
3,896,430,803 visitors served.
forum Join the Word of the Day Mailing List For webmasters
?
Dictionary/
thesaurus
Medical
dictionary
Legal
dictionary
Financial
dictionary
Acronyms
 
Idioms
Encyclopedia
Wikipedia
encyclopedia
?

All-or-None Law

   Also found in: Dictionary/thesaurus, Medical, Legal, Wikipedia 0.01 sec.
all-or-none law [¦ȯl ər ¦nən ‚lȯ]
(neuroscience)
The principle that transmission of a nerve impulse is either at full strength or not at all.

All-or-None Law 

in physiology, the fact that excitable tissue (nervous and muscular) apparently will not respond at all to a stimulus if it is inadequate (subthreshold) or will respond maximally if the stimulus is of threshold magnitude. A further increase in the force of the stimulus will not alter the magnitude or duration of the tissue response. The all-or-none law was derived from a broad interpretation of the data obtained by H. Bowditch (USA, 1871) in stimulating the cardiac ventricle of a frog. Further research demonstrated the relativity of the law (more precisely, principle): a stimulus close to threshold force provokes a local response in the area stimulated; a stimulus of more than threshold force provokes a response, recorded from its action potential, that may in-crease, depending on the condition of the tissue stimulated.

REFERENCE

Nasonov, D. N. “Mestnaia reaktsiia, zakon ’vse ili nichego’ i avtomaticheskaia deiatel’nost’.” Izv. AN SSSR: Seriia biologicheskaia, 1948, no. 4, pp. 381-392.


Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content.
?Page tools
Printer friendly
Cite / link
Feedback
Mentioned in?   Encyclopedia browser?   Full browser?
No references found
 
 
 
Encyclopedia
?

Terms of Use | Privacy policy | Feedback | Advertise with Us | Copyright © 2012 Farlex, Inc.
Disclaimer
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.