RegulationThe brain must not only deal with the mental side of life, but with maintaining life itself through regulation. The brain has automated regulatory control over it's own activation/alertness as well as specific bodily functions such as heart rate, breathing and temperature. Eating, drinking, sleeping and reproduction require some voluntary behavior on our part, but are largely influenced or at least maintained by non-conscious regulatory control. Much of this regulatory control is exerted through the neuroendocrine system utilizing various feedback mechanisms (see Carter, pp. 112-113).
Motor control
The other main category of control the brain attends to is voluntary movement. Movement of the body can be organized a number of way and one way to distinguish between those that are "controlled", under conscious control, versus those that are "automated" which are no longer under conscious control. They no longer demand very much attention or processing resources and may operate without our awareness (example of driving). However, these are not really "automatic" or "UNconcious" as Carter writes (p. 114), I think those terms should be reserved for truly REFLEXIVE behavior that will take place even IF unconscious.
See Reflex Action side bar (p. 114). Strictly speaking, we mean "spinal reflex", can you think of any more complex behavior that you do "reflexively"? (Motor memory? Muscle memory. Implicit memory/learning system foreshadowing Learning & Memory Unit). Motor control involves some feedback from the body and environment, so motor control work in conjunction with sensation and perception.
Planning and Executing Movement (Carter, pp. 114-1119)
Meet the frontal lobes. Pre-motor cortex for planning. Lateral coticospinal tract begins at the primary motor cortex carrying direct voluntary control of specific muscles. Then tract slides through the thalamus to integrate with sensory world, then go deeper and meet the sub-cortical nuclei of the basal ganglia to amplify or suppress unwanted movement. Finally, make it neat: the cerebellum infuses a sense of timing and coordination into your ongoing movements. Final output is down though the spinal cord tracking region wise to the correct motor spinal root where it exits onto it's nerve in the PNS.
Other simpler motor-oriented pathways too, largley UNconcious... example vestibularspinal tract.
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