Date : 01.28.2009

A subcortical oscillatory network contributes to recovery of hand dexterity after spinal cord injury

Category : Press Release
 Section of Communications and Public Liaison, 
Center for Communication Networks
 

Recent studies have shown that after partial spinal-cord lesion at the mid-cervical segment, the remaining pathways compensate for restoring finger dexterity; however, how they control hand/arm muscles has remained unclear. To elucidate the changes in dynamic properties of neural circuits connecting the motor cortex and hand/arm muscles, we investigated the cortico- and inter-muscular couplings of activities throughout the recovery period after the spinal-cord lesion. Activities of antagonist muscle pairs showed co-activation and oscillated coherently at frequencies of 30-46 Hz (c-band) by 1-month post-lesion. Such c-band inter-muscular coupling was not observed pre-lesion, but emerged and was strengthened and distributed over a wide range of hand/arm muscles along with the recovery. Neither the b-band (14-30 Hz) cortico-muscular coupling was observed pre-lesion nor a c-band oscillation was observed in the motor cortex post-lesion. We propose that a subcortical oscillator commonly recruits hand/arm muscles, via remaining pathways such as reticulospinal and/or propriospinal tracts, independent of cortical oscillation, and contributes to functional recovery.