TY - JOUR

T1 - Significance of peripheral feedback in the generation of stepping movements during epidural stimulation of the spinal cord

AU - Musienko, P. E.

AU - Bogacheva, I. N.

AU - Gerasimenko, Yu P.

N1 - Funding Information: This study was supported by the Russian Foundation for Basic Research (Grant No. 04-04-48772), the Russian Foundation for Humanitarian Research (Grant No. 03-06-00315), and the Foundation for Support of Russian Science.

PY - 2007/2

Y1 - 2007/2

N2 - Acute experiments on decerebrate and spinal cats were performed to study the role of the peripheral afferent input from hindlimb receptors in forming the locomotor pattern during epidural stimulation of the spinal cord. Evoked electromyographic activity in the muscles of the hindlimbs was analyzed, along with the kinematic parameters of stepping movements. Epidural stimulation (20-100 μA, 5 Hz) of segments L4-5 of the spinal cord was found to elicit well coordinated walking in the hindlimbs on a moving treadmill band. When the support conditions were changed (non-moving treadmill, unsupported position), epidural stimulation initiated walking with an unstable rhythm. This was associated with a change in the overall nature of the locomotor pattern and the internal structure of the stepping cycle. Alteration of the direction of movement of the treadmill band led to the appearance of backward walking. An increase in the speed of movement of the treadmill band increased the stepping frequency, mainly due to decreases in the extensor phase. Epidural stimulation applied 2-4 h after complete transection of the spinal cord at the T8-T9 level could elicit stepping movements, but only when the treadmill was moving. The role of peripheral feedback in generating the locomotor pattern in conditions of complete disconnection from supraspinal control increased significantly. These data show that peripheral feedback during epidural stimulation of the spinal cord can define the properties of the motor output.

AB - Acute experiments on decerebrate and spinal cats were performed to study the role of the peripheral afferent input from hindlimb receptors in forming the locomotor pattern during epidural stimulation of the spinal cord. Evoked electromyographic activity in the muscles of the hindlimbs was analyzed, along with the kinematic parameters of stepping movements. Epidural stimulation (20-100 μA, 5 Hz) of segments L4-5 of the spinal cord was found to elicit well coordinated walking in the hindlimbs on a moving treadmill band. When the support conditions were changed (non-moving treadmill, unsupported position), epidural stimulation initiated walking with an unstable rhythm. This was associated with a change in the overall nature of the locomotor pattern and the internal structure of the stepping cycle. Alteration of the direction of movement of the treadmill band led to the appearance of backward walking. An increase in the speed of movement of the treadmill band increased the stepping frequency, mainly due to decreases in the extensor phase. Epidural stimulation applied 2-4 h after complete transection of the spinal cord at the T8-T9 level could elicit stepping movements, but only when the treadmill was moving. The role of peripheral feedback in generating the locomotor pattern in conditions of complete disconnection from supraspinal control increased significantly. These data show that peripheral feedback during epidural stimulation of the spinal cord can define the properties of the motor output.

KW - Cat

KW - Decerebration

KW - Electromyographic activity

KW - Epidural stimulation

KW - Locomotor pattern

KW - Peripheral feedback

KW - Spinalization

UR - http://www.scopus.com/inward/record.url?scp=33845904957&partnerID=8YFLogxK

U2 - 10.1007/s11055-007-0166-5

DO - 10.1007/s11055-007-0166-5

M3 - Article

C2 - 17187210

AN - SCOPUS:33845904957

VL - 37

SP - 181

EP - 190

JO - Neuroscience and Behavioral Physiology

JF - Neuroscience and Behavioral Physiology

SN - 0097-0549

IS - 2

ER -