Selectivity of the central control of sensory information in the mammalian spinal cord.

摘要: Afferent feedback from muscle proprioceptors, as well movement-induced activation of skin receptors plays an important role in the patterning motor activity for stepping and postural control. An component this control is presynaptic GABAergic modulation synaptic effectiveness cutaneous afferents, known to change phase with locomotor cycle, during execution voluntary movements, or after a peripheral nerve injury. Recent electrophysiological studies, together ultrastructural observations, indicate that distribution GABAa synapses intraspinal arborizations spindle tendon organ afferents not homogeneous. Namely, some collaterals are targets one, more, interneurones, while other same fibre receive no connections. In addition, both PAD inhibition have local character. This allows, at least principle, decoupling information arising common sensory inputs. A spatially restricted could play significant adjustment Ia onset contractions humans, stimulation skin, compensation following partial denervation muscles. Changes synchronization PAD-mediating interneurones can also profound effect on transmitted by given set afferent fibres. Data presented anesthetized cat, variation spontaneous population dorsal horn neurones laminae III-VI, respond low-threshold produce correlated fluctuations monosynaptic reflexes means pre- postsynaptic mechanisms. It suggested changes level fibres specific tasks.