In Amyotrophic Lateral Sclerosis (ALS), spinal motoneurons degenerate in the order of large motoneurons that innervate fast and fatigable muscle fibers to small motoneurons that innervate slow muscle fibers (Pun et al. 2006). This order of degeneration is peculiar in that it is in direct opposition to the normal order...
During movement, the dendrites of spinal motoneurons receive steady excitatory and inhibitory synaptic input from supraspinal sources, interneurons, and sensory afferents. Motoneurons also have dendritic voltage sensitive ion channels. Most notable is a persistent inward current (PIC), which can enhance the amplitude of synaptic input by several fold. PICs are...