Essential tremor, also referred to as familial tremor, is an autosomal dominant genetic disease and the most common movement disorder. It typically involves a postural and motor tremor of the hands, head or other part...Essential tremor, also referred to as familial tremor, is an autosomal dominant genetic disease and the most common movement disorder. It typically involves a postural and motor tremor of the hands, head or other part of the body. Essential tremor is driven by a central oscillation signal in the brain. However, the corticospinal mechanisms involved in the generation of essential tremor are unclear. Therefore, in this study, we used a neural computational model that includes both monosynaptic and multisynaptic corticospinal pathways interacting with a propriospinal neuronal network. A virtual arm model is driven by the central oscillation signal to simulate tremor activity behavior. Cortical descending commands are classified as alpha or gamma through monosynaptic or multisynaptic corticospinal pathways, which converge respectively on alpha or gamma motoneurons in the spinal cord. Several scenarios are evaluated based on the central oscillation signal passing down to the spinal motoneurons via each descending pathway. The simulated behaviors are compared with clinical essential tremor characteristics to identify the corticospinal pathways responsible for transmitting the central oscillation signal. A propriospinal neuron with strong cortical inhibition performs a gating function in the generation of essential tremor. Our results indicate that the propriospinal neuronal network is essential for relaying the central oscillation signal and the production of essential tremor.展开更多
Nonspecific neuronal activity elicited by intraspinal microstimulation in the intermediate and ventral gray matter of thoracic spinal segments caudal to a complete spinal cord transection significantly increased the r...Nonspecific neuronal activity elicited by intraspinal microstimulation in the intermediate and ventral gray matter of thoracic spinal segments caudal to a complete spinal cord transection significantly increased the rat hindlimb Basso, Beattie, Bresnahan locomotor score by activating the central pattem generator located in the lumbar spinal cord. However, the best region for intraspinal microstimulation is unclear. Using an incomplete spinal cord injury model at T8, we compared the use of intraspinal microstimulation to activate the spinal cord in rats with a spontaneous recovery group. The intraspinal microstimulation group recovered sooner and showed three kinds of movement: the left hindlimb, the left hindlimb toes, and the paraspinal muscles and tails. These had different microstimulation thresholds. There was mild hyperplasia of the astrocytes surrounding the tips of the microelectrodes and slight inflammatory reactions nearby. These results indicate that implantation of microelectrodes was relatively safe and induced minimal damage to the lumbar-sacral spinal cord. Intraspinal microstimulation in the lumbar sacral spinal cord may improve leg movements after spinal cord injury. Non-specific intraspinal microstimulation may be a novel technique for the recovery of spinal cord injuries.展开更多
Spinal cord injury is a devastating condition that is followed by long and often unsuccessful recovery after trauma. The state of the art approach to manage paralysis and concomitant impairments is rehabilitation, whi...Spinal cord injury is a devastating condition that is followed by long and often unsuccessful recovery after trauma. The state of the art approach to manage paralysis and concomitant impairments is rehabilitation, which is the only strategy that has proven to be effective and beneficial for the patients over the last decades. How rehabilitation influences the remodeling of spinal axonal connections in patients is important to understand, in order to better target these changes and define the optimal timing and onset of training. While clinically the answers to these questions remain difficult to obtain, rodent models of rehabilitation like bicycling, treadmill training, swimming, enriched environments or wheel running that mimic clinical rehabilitation can be helpful to reveal the axonal changes underlying motor recovery. This review will focus on the different animal models of spinal cord injury rehabilitation and the underlying changes in neuronal networks that are improved by exercise and rehabilitation.展开更多
基金supported in part by the National Natural Science Foundation of China,No.61361160415,81271684,81501570the Major State Basic Research Development of China(973 Program),No.2011CB013304+1 种基金the Medicine-Engineering Interdisciplinary Research Grant from Shanghai Jiao Tong University in China,No.YG2014ZD09a grant from the Youth Eastern Scholar Program at Shanghai Institutions of Higher Learning in China,No.QD2015007
文摘Essential tremor, also referred to as familial tremor, is an autosomal dominant genetic disease and the most common movement disorder. It typically involves a postural and motor tremor of the hands, head or other part of the body. Essential tremor is driven by a central oscillation signal in the brain. However, the corticospinal mechanisms involved in the generation of essential tremor are unclear. Therefore, in this study, we used a neural computational model that includes both monosynaptic and multisynaptic corticospinal pathways interacting with a propriospinal neuronal network. A virtual arm model is driven by the central oscillation signal to simulate tremor activity behavior. Cortical descending commands are classified as alpha or gamma through monosynaptic or multisynaptic corticospinal pathways, which converge respectively on alpha or gamma motoneurons in the spinal cord. Several scenarios are evaluated based on the central oscillation signal passing down to the spinal motoneurons via each descending pathway. The simulated behaviors are compared with clinical essential tremor characteristics to identify the corticospinal pathways responsible for transmitting the central oscillation signal. A propriospinal neuron with strong cortical inhibition performs a gating function in the generation of essential tremor. Our results indicate that the propriospinal neuronal network is essential for relaying the central oscillation signal and the production of essential tremor.
基金the National Natural Science Foundation of China,No.30770744
文摘Nonspecific neuronal activity elicited by intraspinal microstimulation in the intermediate and ventral gray matter of thoracic spinal segments caudal to a complete spinal cord transection significantly increased the rat hindlimb Basso, Beattie, Bresnahan locomotor score by activating the central pattem generator located in the lumbar spinal cord. However, the best region for intraspinal microstimulation is unclear. Using an incomplete spinal cord injury model at T8, we compared the use of intraspinal microstimulation to activate the spinal cord in rats with a spontaneous recovery group. The intraspinal microstimulation group recovered sooner and showed three kinds of movement: the left hindlimb, the left hindlimb toes, and the paraspinal muscles and tails. These had different microstimulation thresholds. There was mild hyperplasia of the astrocytes surrounding the tips of the microelectrodes and slight inflammatory reactions nearby. These results indicate that implantation of microelectrodes was relatively safe and induced minimal damage to the lumbar-sacral spinal cord. Intraspinal microstimulation in the lumbar sacral spinal cord may improve leg movements after spinal cord injury. Non-specific intraspinal microstimulation may be a novel technique for the recovery of spinal cord injuries.
基金Work in FMB laboratory is supported by grants from the Deutsche Forschungsgemeinschaft(DFG,SFB870)by the Munich Center for Neurosciences(MCN)+2 种基金the Wings for Life foundationsupported by the Munich Center for Systems Neurology(DFG,SyNergyEXC 1010)
文摘Spinal cord injury is a devastating condition that is followed by long and often unsuccessful recovery after trauma. The state of the art approach to manage paralysis and concomitant impairments is rehabilitation, which is the only strategy that has proven to be effective and beneficial for the patients over the last decades. How rehabilitation influences the remodeling of spinal axonal connections in patients is important to understand, in order to better target these changes and define the optimal timing and onset of training. While clinically the answers to these questions remain difficult to obtain, rodent models of rehabilitation like bicycling, treadmill training, swimming, enriched environments or wheel running that mimic clinical rehabilitation can be helpful to reveal the axonal changes underlying motor recovery. This review will focus on the different animal models of spinal cord injury rehabilitation and the underlying changes in neuronal networks that are improved by exercise and rehabilitation.