PSY100H1 Lecture Notes - Central Nervous System, Parasympathetic Nervous System, Efferent Nerve Fiber

• School: UTSG
• Department: Psychology
• Course: PSY100H1
• Professor: Wagner Denton

Document Summary

Most important message: nature and nurture are inextricably entwined: nature (genes) and nurture (social context) interact to affect human behaviour. The nervous system is the body"s electrochemical communication circuitry. Central nervous system (cns: brain & spinal cord. Peripheral nervous system (pns: somatic nervous system, autonomic nervous system. Are the basic unit of the nervous system. Communicate with other neurons through chemical signals. Three types of neurons: sensory neurons (afferent neurons, motor neurons (efferent neurons) Interneurons: hint: same (sensory afferent, motor efferent) Excitatory signals increase the likelihood that the neuron will fire. Inhibitory signals decrease the likelihood that the neuron will fire. They do this by affecting the polarization of the cell. Neurons fire (generate an action potential) if the excitatory input reaches a certain threshold. All-or-nothing principle: a neuron fires with the same potency each time (it either fires or does not fire); but how frequently the neuron fires can vary.