Cortical facilitation of cutaneous reflexes in leg muscles during human gait.
During human gait, cortical convergence on sural nerve reflex pathways was investigated by means of transcranial magnetic stimulation (TMS) of the cortex in five phases of the step cycle during human walking on a treadmill. Muscular responses to paired electrical and magnetic stimulation were compared with the linear summation of the individual stimuli. For both the tibialis anterior (TA) and biceps femoris (BF) muscles, the averaged data of four subjects showed a significant facilitation mainly in the swing phase of the step cycle. It is suggested that facilitation of corticospinal input onto cutaneous reflex pathways is enhanced specifically in these periods of the step cycle.
Pijnappels
M
M
Department of Medical Physics and Biophysics, University of Nijmegen, Geert Grooteplein 21, 6525 EZ Nijmegen, Netherlands.
Van Wezel
B M
BM
Colombo
G
G
Dietz
V
V
Duysens
J
J
D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D004558:Electric Stimulation; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D007866:Leg / Q000294:innervation; D008280:Magnetics; D018482:Muscle, Skeletal / Q000294:innervation*; D011930:Reaction Time / Q000502:physiology*; D012018:Reflex / Q000502:physiology*; D012867:Skin / Q000294:innervation*; D016138:Walking / Q000502:physiology