HKIN 215 Lecture Notes - Lecture 6: Triceps Brachii Muscle, Sensory Nerve, Local Anesthetic
Document Summary
Outline: open-loop control system, response-chaining hypothesis, deafferentation, animal studies, human studies, motor programs: evidence. Objectives: describe the open-loop control system, describe the response chaining hypothesis and evidence against it (deaf- ferentation studies, describe a motor program and 4 lines of evidence supporting it. Compare and contrast the open- and closed- loop models. Processing loop brings information back into the motor system while move- ment occurs: does not wait until the completion of the movement. Response-chaining hypothesis: variant of the open-loop control system, movement initiated by internal or external signal causing a muscle contrac- tion. Sensory feedback from muscles serves as a trigger for the next contraction: many different responses are chained together by feedback responses. If sensory information is eliminated (or delayed or degraded in quality) then there should be a loss of skill or paralysis, because trigger mechanisms are disrupted. Sensory information can be eliminated temporarily via a nerve block or local anaesthetic.
