A chicken without a head running through a barnyard exemplifies how the spinal cord transmits motor signals after connection to the brain has been lost. Along these same lines, researchers in Italy recently identified the mechanisms the human spinal cord uses to control muscle activity even if neural pathways from the brain are physically interrupted.
A media release from Medical University of Vienna (MUV), where the researchers are based, states this is the first time the spinal cord activation patterns for walking have been decoded.
Paraplegics still have neural connections below the site of the injury, and these can trigger rhythmic movements in the legs. “Using statistical methods, we were able to identify a small number of basic patterns that underlie muscle activities in the legs and control periodic activation or deactivation of muscles to produce cyclical movements, such as those associated with walking. Just like a set of building blocks, the neural network in the spinal cord is able to combine these basic patterns flexibly to suit the motor requirement,” says study author Simon Danner, from the Center for Medical Physics and Biomedical Engineering of MedUni Vienna.
The results of the study appear in the journal Brain.
According to the MUV media release, the new findings that associate the basic patterns for triggering and coordinating muscle movements in the legs should provide a boost in creating novel approaches to rehabilitation that utilizes neural networks that remain functional after an event that results in paralysis. Most likely, those approaches would have used electrical stimulation, which is thought to be a potential therapeutic option in helping paraplegics partially regain lost rhythmic movements.
The method by which the neural networks would be stimulated depends upon the patient’s individual injury profile, and likely must be studied further. To help with this, the scientists at MedUni Vienna have developed a unique, noninvasive method for stimulating the spinal cord, which involves attaching electrodes to the surface of the skin. “This method allows easy access to the neural connections in the spinal cord below a spinal injury and can therefore be offered to those suffering from paraplegia without exposing them to any particular medical risks or stresses,” says Karen Minassian, senior author of the current publication.
[Source: Medical University of Vienna]