Psychology Midterm (Ch. 3 definitions, terms, people, etc.) Flashcards
Individual cells in the nervous system that receive, integrate, and transmit information
Neurons
Cell body that contains the nucleus and much of the chemical machinery common to most cells
Soma
Receive information
Dendrites
Long, thin fiber that transmits signals away from the soma to other neurons or to muscles or glands
Axon
Insulating material that encases some axons and functions to speed up transmission of signals moving along the axon
Myelin sheath
Cluster of small knobs where the axon ends and secretes neuotransmitters
Terminal buttons
Junction where information is transmitted from one neuron to another
Points at which neurons interconnect
Synapses
Smal cells found throughout nervous system that provide various types of support for neurons
Nourish and remove waste from neurons, provide insulation around many axons
May also send and receive chemical signals
Glia
Stable negative charge of a neuron when the cell is inactive (-70 millivolts)
Resting potential
Very brief shift in neuron’s electrical charge that travels along an axon
Action potential
Minimum amount of time after an action potential during which another action potential cannot begin
Absolute refractory period
A neuron either fires or it doesn’t, and action potentials are all the same size
Information about the strength of a stimulus may be convey by varying the rate of firing action potentials
All-or-none Law
Microscopic gap between the terminal button of one neuron and the cell membrane of another neuron
Synaptic cleft
Chemicals that transmit information from neuron to another
Neurotransmitters
Sites that are specifically “tuned” to recognize and respond to some neurotransmitters but not to others
Receptor sites
Voltage change at a receptor site on a postsynaptic cell membrane
Graded, vary in size, and increase or decrease probability of a neural impulse in the receiving cell (in proportion to the amount of voltage change)
Postsynaptic potential (PSP)
Positive volt shift that increases likelihood that postsynaptic neuron will fire action potentials
Excitatory PSP
Negative volt shift that decreases the likelihood that the postsynaptic neuron will fire action potentials
Inhibitory PSP
Process in which neurotransmitters are sponged up from the synaptic cleft by presynaptic membrane
Allows recycling of materials
Reuptake
Transmitter involved with discover that cells communicate by releasing chemicals
Contribute to arousal, memory, and attention
Acetylcholine
The three transmitters of dopamine, norepinephrine, and serotonin are included in this group
Monamines
Group of transmitters that consists of amino acids
Only seems to produce inhibitory PSP
Regulation of anxiety, modulation of sleep
GABA
Internally produced chemicals that resemble opiates in structure and effects
Endorphins
System of all nerves that lie outside the brain and spinal cord
Peripheral nervous system
Bundles of fibers (axons) that are routed together in the peripheral nervous system
Nerves
System made up of nerves that connect to voluntary skeletal muscles and to sensory receptors
Somatic nervous system
Axons that carry information inward to the central nervous system from the periphery of the body
Afferent nerve fibers
Axons that carry information outward from the central nervous system to the periphery of the body
Efferent
System made up of nerves that connect to the heart, blood vessels, smooth muscles, and glands
Autonomic nervous system (ANS)
Branch of autonomic nervous system that mobilizes the body’s resources of emergencies
Creates fight-or-flight response
Sympathetic division
Branch of autonomic nervous system that generally conserves bodily resources
Parasympathetic division
Portion of nervous system that consists of brain and spinal cord
Central nervous system (CNS)
Computer-enhanced x ray of brain structure that uses multiple angles of x ray shots
CT scan (computerized tomography)
Scan that uses magnetic fields, radio waves, and computerized enhancements to map out brain structure
MRI scan (magnetic resonance imaging)
Scan that uses radio-active markers to map chemical activity in the brain over time
PET scan (positron emission tomography)
Scan that maps brain activity over time but is more precise that PET scans
fMRI scan (functional magnetic resonance imaging)
Part of brain that includes cerebellum, medulla, and pons
Hindbrain
Attached to spinal cord and controls unconscious but essential functions
Medulla
Bridge of fibers that connects brainstem with cerebellum
Involved with sleep and arousal
Pons
Relatively large and deeply folded structure adjacent to back surface of brain stem
“Little brain”
Involved in coordination of movement and critical to sense of equilibrium
Cerebellum
Segment of brainstem that lies between hindbrain and forebrain
Concerns integrating sensory processes
Midbrain
Largest and most complex region of the brain
Consists of thalamus, hypothalamus, limbic system, and cerebrum
Forebrain
Structure in forebrain that all sensory information must pass to get to the cerebral cortex
Thalamus
Structure near base of forebrain that regulates basic biological needs (the four “f’s”)
Hypothalamus
Loosely connected network of structures located roughy along the border of cerebral cortex and deeper subcortical areas
Contains memory processes and “pleasure centers”
Limbic system
Largest and most complex part of the human brain
Contains areas responsible for most complex mental activities (learning, thinking, remembering, consciousness)
Cerebrum
Outer layer of cerebum
Cerebral cortex
Major structure that connects the two cerebral hemispheres
Corpus callosum
Lobe that includes cortical area where most visual signals are sent and visual processing is done
Occipital lobe (primary visual cortex)
Lobe that registers sense of touch
Partietal lobe (primary somatosensory cortex)
Lobe devoted to auditory processing
Temporal lobe (primary auditory cortex)
Largest lobe in human brain
Contains principal areas that control movement of muscles
Frontal lobe (primary motor cortex)
Neurons activated by performing an action or by seeing another person perform the same action
Mirror neurons
Surgery where the bundle of fibers that connects the cerebral hemispheres is cut to reduce severity of epileptic seizures
Split-brain surgery
System that consists of glands that secrete chemicals into the bloodstream to help control bodily functioning
Endocrine system
Chemical substances released by endocrine glands
Hormones
Pattern of hormone release that is several times per day in brief bursts for only a few minutes
Pulsatile
Gland that releases large variety of hormones that fan out within the body, stimulating actions in the other endocrine glands
“Master gland”
Pituitary gland
This part of the nervous system mostly controls the endocrine system
Hypothalamus
