Sensorimotor transformation in a spinal motor system

To use sensory information from the skin to guide motor behaviour the central nervous system must transform sensory coordinates into movement coordinates. As yet, the basic principles of this crucial neural computation are unclear. One motor system suitable as a model for the study of such transformations is the spinal withdrawal reflex system. The spatial organization of the cutaneous input to these reflexes has been characterized, and we now introduce a novel method of motion analysis permitting a quantitative analysis of the spatial input-output relationship in this motor system. For each muscle studied, a “mirror-image” relationship was found between the spatial distribution of reflex gain for cutaneous input and the pattern of cutaneous unloading ensuing on contraction. Thus, there is an “imprint” of the movement pattern on this motor system permitting effective sensorimotor transformation. This imprint may indicate the presence of a learning process which utilizes the sensory feedback ensuing on muscle contraction.

[1]  J. Schouenborg,et al.  Differential Effects of a Distant Noxious Stimulus on Hindlimb Nociceptive Withdrawal Reflexes in the Rat , 1992, The European journal of neuroscience.

[2]  J Schouenborg,et al.  Functional organization of the nociceptive withdrawal reflexes , 1992, Experimental Brain Research.

[3]  J. Schouenborg,et al.  Topography and nociceptive receptive fields of climbing fibres projecting to the cerebellar anterior lobe in the cat. , 1991, The Journal of physiology.

[4]  William D. Willis,et al.  Sensory Mechanisms of the Spinal Cord , 1979, Springer US.

[5]  W. Willis,et al.  Sensory Mechanisms of the Spinal Cord , 1991, Springer US.

[6]  B. Ripley.  Statistical inference for spatial processes , 1990 .

[7]  E. Schomburg.  Spinal sensorimotor systems and their supraspinal control , 1990, Neuroscience Research.

[8]  C. Sherrington.  Flexion‐reflex of the limb, crossed extension‐reflex, and reflex stepping and standing , 1910, The Journal of physiology.

[9]  M. Garwicz,et al.  Distribution of Cutaneous Nociceptive and Tactile Climbing Fibre Input to Sagittal Zones in Cat Cerebellar Anterior Lobe , 1992, The European journal of neuroscience.

[10]  J Schouenborg,et al.  The postsynaptic dorsal column pathway mediates cutaneous nociceptive information to cerebellar climbing fibres in the cat. , 1991, The Journal of physiology.

[11]  M. Swash,et al.  The Motor Cortex , 1990 .

[12]  E. Jankowska.  Interneuronal relay in spinal pathways from proprioceptors , 1992, Progress in Neurobiology.