广东外语外贸大学普通心理学课件第二章 Brain and Behavior.pptVIP

Chapter 2Brain and Behavior Neuron and Its Parts Neuron: Individual nerve cell Dendrites: Receive messages from other neurons Soma: Cell body; body of the neuron Axon: Fiber that carries information away from the cell body Axon Terminals: Branches that link the dendrites and somas of other neurons The Nerve Impulse Resting Potential: Electrical charge of an inactive neuron Threshold: Trigger point for a neuron’s firing Action Potential: Nerve impulse Negative After-Potential: When a neuron is less willing to fire Synapses Messages from one neuron to another pass over a microscopic gap called a synapse Synapse: Microscopic gap between two neurons over which messages pass Neurotransmitters Chemicals that alter activity in neurons; brain chemicals Acetylcholine: Activates muscles Dopamine: Muscle control Serotonin: Mood and appetite control ? Receptor Site: Areas on the surface of neurons and other cells that are sensitive to neurotransmitters Neural Regulators Neural Peptides: Regulate activity of other neurons Enkephalins: Relieve pain and stress; similar to endorphins Endorphins: Released by pituitary gland; also help to relieve pain Nerves and Neurons Nerves: Large bundles of axons and dendrites Myelin: Fatty layer of tissue that coats axons Multiple Sclerosis (MS) occurs when myelin layer is destroyed; numbness, weakness, and paralysis occur Neurilemma: Thin layer of cells wrapped around axons outside brain and spinal cord; forms a tunnel where damaged fibers go as they repair themselves Neurogenesis: Production of new brain cells Neural Networks Central Nervous System (CNS): Brain and spinal cord Peripheral Nervous System: All parts of the nervous system outside of the brain and spinal cord Somatic System: Links spinal cord with body and sense organs; controls voluntary behavior Autonomic System: Serves internal organs and glands; controls automatic functions such as heart rate and blood pressure Two Divisions of the Autonomic System Sympathetic: Arou