In Vitro locomotor pattern

In these last years, growing attention has been drawn upon the use of epidural electrical stimulation applied to the dorsal spinal cord to counteract a wide range of neurological disturbances. Among the different therapeutical purposes, should be mentioned the recovery of standing posture and locomotion after a spinal cord injury. Currently, these applications exploit the same stimulating protocol that has been used for decades, which is composed of a train of stereotyped impulses, square or sinusoidal, with frequencies that vary within a limited range.

In order to design innovative and more effective stimulating patterns to be introduced in clinics in the future, we utilize in our lab the in vitro neonatal rat spinal cord preparation, where, in response to electrical pulses delivered to a dorsal root, it can be observed an episode of electrical discharges corresponding to the rhythmic and alternated activation of the extensor and flexor motor pools on the two sides of the cord, which represent the neuronal program at the base of locomotion.

Innovative programmable electrostimulators and last generation electrodes are employed to deliver a wide range of stimulating wave shapes, obtained artificially through off-line analysis or sampled directly from biological signals, such as events of rhythmic activity induced in the preparation in response to neurochemicals. Moreover, in the laboratory for human movement analysis within the IMFR Institute (Gervasutta Hospital, Udine), kinematic analysis of lower limbs was performed and simultaneous electromyographic recordings were taken from several muscles of adult volonteers during the execution of different motor tasks and are used to sample different noisy waveforms to test as new stimulating patterns. Furthermore, the possibility that selected pharmacological drugs, applied in conjunction with electrical stimulation, facilitate the appearance of locomotor-like oscillations is explored by studying the pharmacology of spinal neuronal circuits for locomotion with electrophysiological intracellular recordings from single motoneuron or with extracellular recordings from motor nerve.


Copyright © 2013 SISSA. Scuola Internazionale Superiore di Studi Avanzati

via Bonomea, 265 - 34136 Trieste ITALY