Introduction: In this study we investigated the effects of aging on corticospinal tract conduction by measuring the corticoconus motor conduction time (CCCT).
Methods: Motor evoked potentials were recorded from the right tibialis anterior muscle in 100 healthy volunteers. To activate the most proximal part of the cauda equina, magnetic stimulation was performed using a MATS coil over the L1 spinous process (L1-level latency). Transcranial magnetic stimulation of the motor cortex was also conducted (cortical latency). To obtain the CCCT, the L1-level latency was subtracted from the cortical latency.
Results: Age was significantly correlated with L1-level latency, but it was not significantly correlated with CCCT.
Conclusions: CCCT is the most direct indicator of corticospinal tract conduction, whereas L1-level latency reflects whole peripheral motor conduction. Central motor conduction was found to be relatively less affected by aging compared with peripheral motor conduction.
Copyright © 2012 Wiley Periodicals, Inc.