PSY100H1 Lecture Notes - Lecture 5: Central Nervous System, Parasympathetic Nervous System, Somatic Nervous System

• School: UTSG
• Department: Psychology
• Course: PSY100H1
• Professor: Ashley Waggoner Denton

Document Summary

The nervous system: the body"s electrochemical communication circuitry, central nervous system (cns)- brain, spinal cord, peripheral nervous system (pns)- arms, legs, everything outside. Autonomic nervous system: sympathetic & parasympathetic nervous system. Neurons: basic unit of nervous system, operate through electrical impulses, communicate with other neurons via chemical signals between neighbouring neurons, three types: Sensory neuron (afferent neurons) sensing info from the external environment. Interneurons: bridges between a motor and sensory neuron. More dendrites neuron have, increasing receptive feel; able to collect more info. Cell body collects and integrates the incoming info. Neurons " re" action potentials: action potential: the neural impulse that passes along the axon and subsequently causes release of chemicals from terminal buttons. "depolarization: neurons fire if the excitatory input reaches a certain threshold, all-or-none principle > a neuron fires with the same potency each time (either fires or doesn"t) But how frequently the neuron fires can vary: myelinated axon helps action potential travel quicker;