Push-pull control of motor output. J Neurosci 2012 Mar 28;32(13):4592-9
Date
03/30/2012Pubmed ID
22457505Pubmed Central ID
PMC3335194DOI
10.1523/JNEUROSCI.4709-11.2012Scopus ID
2-s2.0-84859066926 (requires institutional sign-in at Scopus site) 29 CitationsAbstract
Inhibition usually decreases input-output excitability of neurons. If, however, inhibition is coupled to excitation in a push-pull fashion, where inhibition decreases as excitation increases, neuron excitability can be increased. Although the presence of push-pull organization has been demonstrated in single cells, its functional impact on neural processing depends on its effect on the system level. We studied push-pull in the motor output stage of the feline spinal cord, a system that allows independent control of inhibitory and excitatory components. Push-pull organization was clearly present in ankle extensor motoneurons, producing increased peak-to-peak modulation of synaptic currents. The effect at the system level was equally strong. Independent control of the inhibitory component showed that the stronger the background of inhibition, the greater the peak force production. This illustrates the paradox at the heart of push-pull organization: increased force output can be achieved by increasing background inhibition to provide greater disinhibition.
Author List
Johnson MD, Hyngstrom AS, Manuel M, Heckman CJAuthor
Allison Hyngstrom PhD Associate Professor in the Physical Therapy department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AnimalsCats
Female
Male
Membrane Potentials
Motor Neurons
Muscle, Skeletal
Neural Inhibition
Spinal Cord
Synaptic Transmission