Autor: |
McLean DL; Department of Neurobiology and Behavior, w103 Mudd Hall Cornell University, Ithaca, New York 14853, USA., Masino MA, Koh IY, Lindquist WB, Fetcho JR |
Jazyk: |
angličtina |
Zdroj: |
Nature neuroscience [Nat Neurosci] 2008 Dec; Vol. 11 (12), pp. 1419-29. Date of Electronic Publication: 2008 Nov 09. |
DOI: |
10.1038/nn.2225 |
Abstrakt: |
The classic 'size principle' of motor control describes how increasingly forceful movements arise by the recruitment of motoneurons of progressively larger size and force output into the active pool. We explored the activity of pools of spinal interneurons in larval zebrafish and found that increases in swimming speed were not associated with the simple addition of cells to the active pool. Instead, the recruitment of interneurons at faster speeds was accompanied by the silencing of those driving movements at slower speeds. This silencing occurred both between and within classes of rhythmically active premotor excitatory interneurons. Thus, unlike motoneurons, there is a continuous shift in the set of cells driving the behavior, even though changes in the speed of the movements and the frequency of the motor pattern appear to be smoothly graded. We conclude that fundamentally different principles may underlie the recruitment of motoneuron and interneuron pools. |
Databáze: |
MEDLINE |
Externí odkaz: |
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