Sensory functions Motor functions Examples Low complexity functions Sensation used for automatic responses Automatic movements of body in response to stimuli Middle complexity functions Inputs to upper brainstem cerebellum basal ganglia Automatic synchrony and coordination of movement High complexity functions Integration and conscious awareness of afferent input Conscious planning and preparation of purposeful movement Most complex most rostral cortex basal ganglia cerebellum brain stem Least complex most caudal Spinal cord The higher the afferents project the more complex the associated function Likewise the higher the origin of the efferents the more complex the associated function Simple reflex arc at level of spinal cord e g pulling hand away from hot pot automatic does not involve conscious control Complex reflexes at level of mid brain e g synchrony of vestibular input with eye head and postural positioning automatic coordination and pre programming of mvmnt Identifying a target on which you are going to act and then acting on that target e g kicking soccer ball planning and organizing a get together Thus afferents that project to cortex efferents that originate in cortex represent the most complex functions Spinal cord grey matter on the side White matter outside Brain outside grey matter Inside white matter Synapses on the grey matter Patterns in the nervous system as a whole are exemplified in a fundamental way at spinal cord level Anatomy aggregations of cell bodies and associated dendrites grey matter where the synapses happen sent along axons Bundles of myelinated axons white matter where action potentials are Physiology demonstrates synaptic relay of impulses along a pathway And potential patterns of breakdown Simple reflex arc at level of spinal cord cord in between messages synapses to motor neuron CNS to muscles Sensory neuron bring info in synapses to interneuron in spinal