During this week’s lecture we learned about the motor system and its connection to the brain. The general function and construction of the muscle wasn’t new information, but it was a good repetition, and a couple of new terms were learned such as: motor neuron pool, t tubule, and golgi tendon organ.
The different pathways for in which the brain communicate with the motor neurons of the spinal cord were also new knowledge. The two major groups of pathways are lateral pathways and ventromedial pathways. Axons in the lateral pathway are involved in the control of voluntary movements of distal muscles, and axons in the ventromedial pathway control postural muscles. The axons in the lateral column are under direct cortical control, whereas the axons in the ventromedial pathway are under brain stem control.
One disorder that was mentioned on the lecture and effects the motor system, is Parkinson’s disease. Parkinson’s is a disorder of the central nervous system, which has symptoms in the motor system such as: shaking, slowness of movements, and rigidity. The motor symptoms are a result of cell death in substantia nigra, which is a cell group in the midbrain that uses the neurotransmitter dopamine to transfer the inputs to striatum. One therapy for Parkinson’s disease is to use the compound dopa, which can increase the levels of dopamine.