- Kohnstamm's phenomenon
First described by German neurologist
Oskar Kohnstamm (1871-1917) in 1915, Kohnstamm's phenomenon is a sustained involuntary contraction of amuscle after a prolonged voluntary contraction. The simplest demonstration is to have a subject press against the wall by abducting the arm and then ask to step away from the wall. The arm will involuntarily rise.Russian scientists [http://www.ras.ru/win/db/show_per.asp?P=.id-1047.ln-ru Victor Gurfinkel] , [http://geocities.com/mikhail_a_lebedev/ Mikhail Lebedev] and Yuri Levick used Kohnstamm's phenomenon to activate tonogenic structures in humans and thereby demonstrate postural automatisms, such as neck reflexes.
See also
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Motor control References
* Kohnstamm, O. Demonstration einer Katatonieartigen Erscheimung beim Gesunden (Katatonusversuch). Neurol. Zentral B1 34S: 290-291, 1915.
* Gurfinkel, V.S., Lebedev, M.A., Levick, Yu.S. (1992) What about the so-called neck reflexes in humans? In: A. Bertoz, W. Graf, P. P. Vidal (Eds) [http://www.oup.com/us/catalog/general/subject/LifeSciences/VertebrateZoology/~~/cHI9MTAmcGY9MCZzcz1hdXRob3IuYXNjJnNmPWFsbCZzZD1hc2Mmdmlldz11c2EmY2k9MDE5NTA2ODIwMw= The Head-Neck Sensory Motor System] , New York, Oxford, Oxford University Press: 543-547.
* Gurfinkel, V.S., Levik, Yu.S., Lebedev, M.A. (1989) [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=2770916&query_hl=4 Immediate and remote postactivation effects in the human motor system.] Neirofiziologiya (Kiev) 21: 343-351. Translation into English: Neurophysiology 21: 247-253.
* Gurfinkel, V.S., Levik, Yu.S., Lebedev, M.A. (1989) [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=2752900&query_hl=4 Postural automatisms revealed by enhancement of the tonic background.] Doklady Akademii Nauk SSSR 305:1266-1269.
* Duclos C, Cerebral correlates of the “Kohnstamm phenomenon”: An fMRI study, NeuroImage Vol 34, Issue 2, 15 January 2007, Pages 774-783
* Wright WG, Interaction of involuntary post-contraction activity with locomotor movements, Exp Brain Res. 2006 Feb 169(2): 255–260
* Mathis J, Facilitation of motor evoked potentials by postcontraction response (Kohnstamm phenomenon), Electroencephalogr Clin Neurophysiol. 1996 Aug
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