PSYC 111 Lecture Notes - Lecture 19: Central Nervous System, Peripheral Nervous System, Autonomic Nervous System
Document Summary
The worm c. elegans: 1 mm in length; 302 neurons. Homo sapiens: 1,680 mm in length; - 100 billion neurons approximately. The central nervous system (cns) is composed of the brain and spinal cord. The peripheral nervous system (pns) carries information to and from the rest of the body. Somatic nervous system: controls sensory input and motor output. Autonomic nervous system: controls the internal organs: neurons communicating between the brain and the organs. Sympathetic nervous system: mobilizes the body during periods of emotion and stress: examples: dilates the pupils, accelerates heartbeat, improves airflow. Parasympathetic nervous system: operates the body when we are relaxed: examples: constricts the pupils, slows heartbeat, facilitates digestion. Brain stem: medulla: co(cid:374)trols (cid:862)pri(cid:373)itive(cid:863) fu(cid:374)(cid:272)tio(cid:374)s: heart, (cid:271)reathi(cid:374)g, pons: involved in sleep/wake cycles, dreams, regulates when we feel relatively alert and when we feel tired. Regulates movement and balance; involved in reflexes, simple skills, classical conditioning.
