For individuals with paraplegia, standing up requires activation of paralyzed leg muscles by an artificial functional electrical stimulation (FES) controller and voluntary control of arm forces by the individual.
Artificial neural network models were developed to predict voluntary arm forces from measured angular positions of the ankle, knee, and hip joints during FES-assisted standing up in paraplegia.
Data were collected from eight paraplegic subjects in repeated standing-up trials.
The predictions of the models closely followed both the training and validation data, showing good accuracy and generalization.
The comparison of the models showed that there are striking similarities among the voluntary controls adopted by different subjects.
Each subject develops his/her own "personal strategy" to control the arm forces, which is consistent from trial to trial.
(Kamnik et al. 2005)
The central nervous system contains internal models that represent movements.
Forward models are predictions between motor commands and the resulting changes in the sensorimotor system.
Study by Hotz-Boendermaker et al., 2008:
Used fMRI to look at activation patterns during motor imagery
When asked to mentally move their paralyzed feet, the sensorimotor and imagery cortices were activiated - same activation in healthy people.
Also, when asked to attempt to move their paralyzed foot, the same network was stimulated compared to when healthy participants actually moved their paralyzed foot.
-Paraplegics have the potential to initiate and control foot movements
Artificial neural network models were developed to predict voluntary arm forces from measured angular positions of the ankle, knee, and hip joints during FES-assisted standing up in paraplegia.
Data were collected from eight paraplegic subjects in repeated standing-up trials.
The predictions of the models closely followed both the training and validation data, showing good accuracy and generalization.
The comparison of the models showed that there are striking similarities among the voluntary controls adopted by different subjects.
Each subject develops his/her own "personal strategy" to control the arm forces, which is consistent from trial to trial.
(Kamnik et al. 2005)
The central nervous system contains internal models that represent movements.
Forward models are predictions between motor commands and the resulting changes in the sensorimotor system.
Study by Hotz-Boendermaker et al., 2008:
Used fMRI to look at activation patterns during motor imagery
When asked to mentally move their paralyzed feet, the sensorimotor and imagery cortices were activiated - same activation in healthy people.
Also, when asked to attempt to move their paralyzed foot, the same network was stimulated compared to when healthy participants actually moved their paralyzed foot.
-Paraplegics have the potential to initiate and control foot movements