@article {3390,
	title = {Locomotor impact of beneficial or nonbeneficial H-reflex conditioning after spinal cord injury.},
	journal = {J Neurophysiol},
	volume = {111},
	year = {2014},
	month = {03/2014},
	pages = {1249-58},
	abstract = {When new motor learning changes neurons and synapses in the spinal cord, it may affect previously learned behaviors that depend on the same spinal neurons and synapses. To explore these effects, we used operant conditioning to strengthen or weaken the right soleus H-reflex pathway in rats in which a right spinal cord contusion had impaired locomotion. When up-conditioning increased the H-reflex, locomotion improved. Steps became longer, and step-cycle asymmetry (i.e., limping) disappeared. In contrast, when down-conditioning decreased the H-reflex, locomotion did not worsen. Steps did not become shorter, and asymmetry did not increase. Electromyographic and kinematic analyses explained how H-reflex increase improved locomotion and why H-reflex decrease did not further impair it. Although the impact of up-conditioning or down-conditioning on the H-reflex pathway was still present during locomotion, only up-conditioning affected the soleus locomotor burst. Additionally, compensatory plasticity apparently prevented the weaker H-reflex pathway caused by down-conditioning from weakening the locomotor burst and further impairing locomotion. The results support the hypothesis that the state of the spinal cord is a "negotiated equilibrium" that serves all the behaviors that depend on it. When new learning changes the spinal cord, old behaviors undergo concurrent relearning that preserves or improves their key features. Thus, if an old behavior has been impaired by trauma or disease, spinal reflex conditioning, by changing a specific pathway and triggering a new negotiation, may enable recovery beyond that achieved simply by practicing the old behavior. Spinal reflex conditioning protocols might complement other neurorehabilitation methods and enhance recovery.},
	keywords = {Animals, Conditioning, Operant, Female, H-Reflex, Learning, Locomotion, Male, Rats, Rats, Sprague-Dawley, Spinal Cord Injuries},
	issn = {1522-1598},
	doi = {10.1152/jn.00756.2013},
	url = {http://www.ncbi.nlm.nih.gov/pubmed/24371288},
	author = {Yi Chen and Lu Chen and Liu, Rongliang and Wang, Yu and Xiang Yang Chen and Jonathan Wolpaw}
}
@article {3389,
	title = {The simplest motor skill: mechanisms and applications of reflex operant conditioning.},
	journal = {Exerc Sport Sci Rev},
	volume = {42},
	year = {2014},
	month = {04/2014},
	pages = {82-90},
	abstract = {Operant conditioning protocols can change spinal reflexes gradually, which are the simplest behaviors. This article summarizes the evidence supporting two propositions: that these protocols provide excellent models for defining the substrates of learning and that they can induce and guide plasticity to help restore skills, such as locomotion, that have been impaired by spinal cord injury or other disorders.},
	keywords = {Animals, Conditioning, Operant, H-Reflex, Humans, Motor Skills, Muscle, Skeletal, Neuronal Plasticity, Reflex, Spinal Cord, Spinal Cord Injuries},
	issn = {1538-3008},
	doi = {10.1249/JES.0000000000000010},
	url = {http://www.ncbi.nlm.nih.gov/pubmed/24508738},
	author = {Thompson, Aiko K and Jonathan Wolpaw}
}
