Normal movement is produced by an interaction of neural circuits, primarily in the spinal cord, and the musculoskeletal system. As a means of investigating this important interaction, the goal of this project will be to identify output elements of this spinal circuitry, the smallest portions of the musculoskeletal system with which spinal circuits might interact. In particular we will evaluate whether neuromuscular compartments might function as output elements by analyzing their mechanical properties. Neuromuscular compartments in the cat lateral gastrocnemius and medial gastrocnemius muscles and the human flexor carpi radialis and extensor carpi radialis longus muscles will be studied. Using a multi-axis force-moment transducer, we will determine the torques, produced either by compartment activation or by stimulation of single motor units, about three orthogonal axes at both of the joints (ankle and knee or wrist and elbow) crossed by these muscles. If compartments are output elements, then we postulate that they will exert mechanical effects, as measured by these torques, which are unique, and which are not altered when multiple compartments are activated together. We propose also that all of the motor units in a compartment would be expected to exert the same mechanical effect on the skeletal system if the compartments are output elements. The results of this study will provide important background data for other projects in this PPG as well as providing a scientific basis for the identification of output elements of spinal circuits. We anticipate that these findings will be useful for movement scientists studying the elaboration of movement by the nervous system and by rehabilitationists who have as part of their clinical role the application of therapeutic modalities involving muscle.

Project Start
1998-02-01
Project End
1999-01-31
Budget Start
1997-10-01
Budget End
1998-09-30
Support Year
4
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Emory University
Department
Type
DUNS #
042250712
City
Atlanta
State
GA
Country
United States
Zip Code
30322
Eftekhar, Amir; Norton, James J S; McDonough, Christine M et al. (2018) Retraining Reflexes: Clinical Translation of Spinal Reflex Operant Conditioning. Neurotherapeutics :
Norton, James J S; Wolpaw, Jonathan R (2018) Acquisition, Maintenance, and Therapeutic Use of a Simple Motor Skill. Curr Opin Behav Sci 20:138-144
Gregor, Robert J; Maas, Huub; Bulgakova, Margarita A et al. (2018) Time course of functional recovery during the first 3 mo after surgical transection and repair of nerves to the feline soleus and lateral gastrocnemius muscles. J Neurophysiol 119:1166-1185
Chen, Yi; Chen, Lu; Wang, Yu et al. (2017) Why New Spinal Cord Plasticity Does Not Disrupt Old Motor Behaviors. J Neurosci 37:8198-8206
Pantall, Annette; Hodson-Tole, Emma F; Gregor, Robert J et al. (2016) Increased intensity and reduced frequency of EMG signals from feline self-reinnervated ankle extensors during walking do not normalize excessive lengthening. J Neurophysiol 115:2406-20
Chen, Xiang Yang; Wang, Yu; Chen, Yi et al. (2016) Ablation of the inferior olive prevents H-reflex down-conditioning in rats. J Neurophysiol 115:1630-6
Gordon, Tessa; English, Arthur W (2016) Strategies to promote peripheral nerve regeneration: electrical stimulation and/or exercise. Eur J Neurosci 43:336-50
Zhu, Xiya; Ward, Patricia J; English, Arthur W (2016) Selective Requirement for Maintenance of Synaptic Contacts onto Motoneurons by Target-Derived trkB Receptors. Neural Plast 2016:2371893
Farrell, Brad J; Bulgakova, Margarita A; Sirota, Mikhail G et al. (2015) Accurate stepping on a narrow path: mechanics, EMG, and motor cortex activity in the cat. J Neurophysiol 114:2682-702
Krakowiak, Joey; Liu, Caiyue; Papudesu, Chandana et al. (2015) Neuronal BDNF signaling is necessary for the effects of treadmill exercise on synaptic stripping of axotomized motoneurons. Neural Plast 2015:392591

Showing the most recent 10 out of 93 publications