Does Motor Learning Occur in the Spinal Cord?

It is becoming clear that the plasticity of the sensory-motor networks of the adult mammalian lumbosacral spinal cord is much greater than and is more dependent on the specific patterns of use than has been previously assumed. Using a wide variety of experimental paradigms in which the lumbar spinal cord is isolated from the brain, it has been shown that the lumbosacral spinal cord can learn to execute stepping or standing more successfully if that specific task is practiced. It also appears that the sensory input associated with the motor task and/or the manner in which it is interpreted by the spinal cord are important components of the neural network plasticity. Early evidence suggests that several neurotransmitter systems in the spinal cord, to include glycinergic and GABAergic systems, adapt to repetitive use. These studies extend a growing body of evidence suggesting that memory and learning are widely distributed phenomena within the central nervous system. NEUROSCIENTIST 3:287–294, 1997

[1]  C. Becker.  Disorders of the inhibitory glycine receptor: the spastic mouse , 1990, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[2]  V. Edgerton,et al.  Relative independence of metabolic enzymes and neuromuscular activity. , 1984, Journal of applied physiology: respiratory, environmental and exercise physiology.

[3]  J R Wolpaw,et al.  Operant conditioning of H-reflex changes synaptic terminals on primate motoneurons. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[4]  V. Edgerton,et al.  Interrelationships of contraction time, Vmax, and myosin ATPase after spinal transection. , 1984, Journal of applied physiology: respiratory, environmental and exercise physiology.

[5]  J. Wolpaw,et al.  Memory traces in primate spinal cord produced by operant conditioning of H-reflex. , 1989, Journal of neurophysiology.

[6]  S. Grillner,et al.  The locomotion of the low spinal cat. I. Coordination within a hindlimb. , 1980, Acta physiologica Scandinavica.

[7]  N. Kudo,et al.  Disparity of motoneurone and muscle differentiation following spinal transection in the kitten. , 1978, The Journal of physiology.

[8]  J. Wolpaw,et al.  Operantly Conditioned Plasticity in Spinal Cord a , 1991, Annals of the New York Academy of Sciences.

[9]  J. Bloedel,et al.  Substrates for Motor Learning Does the Cerebellum Do It All? a , 1991, Annals of the New York Academy of Sciences.

[10]  V. Reggie Edgerton,et al.  Coordination of motor pools controlling the ankle musculature in adult spinal cats during treadmill walking , 1991, Brain Research.

[11]  R. Ryall,et al.  Glycine‐mediated inhibitory transmission of group 1A‐excited inhibitory interneurones by Renshaw cells. , 1976, The Journal of physiology.

[12]  R. Roy,et al.  Fiber type and fiber size changes in selected thigh muscles six months after low thoracic spinal cord transection in adult cats: Exercise effects , 1986, Experimental Neurology.

[13]  George Adrian Horridge,et al.  Learning of leg position by the ventral nerve cord in headless insects , 1962, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[14]  M. M. Patterson,et al.  Fixation of spinal reflexes in rats by central and peripheral sensory input. , 1981, Journal of comparative and physiological psychology.

[15]  S. Grillner,et al.  Central Generation of Locomotion in Vertebrates , 1976 .

[16]  THE SENSITIZATION OF MOTONEURONES BY PARTIAL "DENERVATION" , 1939 .

[17]  E. Culler,et al.  Conditioning in the spinal dog , 1940 .

[18]  M. M. Patterson,et al.  Effects of a classical conditioning paradigm on hind-limb flexor nerve response in immobilized spinal cats. , 1973, Journal of comparative and physiological psychology.

[19]  V R Edgerton,et al.  Soleus motor units in chronic spinal transected cats: physiological and morphological alterations. , 1986, Journal of neurophysiology.

[20]  Classical conditioning, sensitization and habituation in the spinal cat , 1975, Physiology & Behavior.

[21]  V. Edgerton,et al.  EMG activity of slow and fast ankle extensors following spinal cord transection. , 1984, Journal of applied physiology: respiratory, environmental and exercise physiology.

[22]  V R Edgerton,et al.  Chronic spinal cord-injured cats: surgical procedures and management. , 1992, Laboratory animal science.

[23]  S. Rossignol,et al.  Pharmacology of locomotion: an account of studies in spinal cats and spinal cord injured subjects. , 1993, The Journal of the American Paraplegia Society.

[24]  P. Rudomín,et al.  Pharmacologic analysis of inhibition produced by last-order intermediate nucleus interneurons mediating nonreciprocal inhibition of motoneurons in cat spinal cord. , 1990, Journal of neurophysiology.

[25]  Trevor Drew,et al.  Phasic Modulation of Reflexes during Rhythmic Activity , 1986 .

[26]  S. Grillner.  Neurobiological bases of rhythmic motor acts in vertebrates. , 1985, Science.

[27]  A. A. Buerger,et al.  Long-term alteration of leg position due to shock avoidance by spinal rats. , 1971, Experimental neurology.

[28]  R. J. Gregor,et al.  Effects of training on the recovery of full-weight-bearing stepping in the adult spinal cat , 1986, Experimental Neurology.

[29]  S. Rossignol,et al.  The effects of clonidine and yohimbine on locomotion and cutaneous reflexes in the adult chronic spinal cat , 1987, Brain Research.

[30]  V R Edgerton,et al.  The plasticity of skeletal muscle: effects of neuromuscular activity. , 1991, Exercise and sport sciences reviews.

[31]  B. Dobkin,et al.  Can the mammalian lumbar spinal cord learn a motor task? , 1994, Medicine and science in sports and exercise.

[32]  M. M. Patterson.  17 – Mechanisms of Classical Conditioning of Spinal Reflexes1 , 1980 .

[33]  S. Cullheim,et al.  Two kinds of recurrent inhibition of cat spinal alpha‐motoneurones as differentiated pharmacologically. , 1981, The Journal of physiology.

[34]  R. J. Gregor,et al.  Weight-bearing hindlimb stepping in treadmill-exercised adult spinal cats , 1990, Brain Research.

[35]  S. Rossignol,et al.  Recovery of locomotion after chronic spinalization in the adult cat , 1987, Brain Research.

[36]  S Grillner,et al.  Control of locomotion in vertebrates: spinal and supraspinal mechanisms. , 1988, Advances in neurology.