PSL300H1 Lecture Notes - Lecture 17: Rubrospinal Tract, Reticular Formation, Vestibulospinal Tract
Document Summary
Activate huge sets of muscles; red nuc focuses on discrete muscles (like motor cortex) Motor cortex: more space available so motor area took over here, able to program more synergies; programs more recent uses of distant limbs; ex. Speech at bottom: biggest representations of speech & finger, most synergies, highest receptor density. Feet on medial walls btwn hemispheres; upside-down representation of body. Knob, speech muscles at lateral side above lateral fissure. Some axons don"t cross variable in ppl but never. >15% of entire tract, in some ppl nothing probably depends on motor bhvrs the indiv trains. Coding direction of reach: particular movements/ sets of synergies, ex. Most evident in language programming certain sound combinations specific for lang you speak. Thumb cotricomotoneural cell in column involved in thumb flexion, neuron projects directly to pyr cells projecting directly to motorneurons. Precision grip holding object btwn thumb & finger. Very active, precedes onset of movement ms earlier.
