psychology ch 4

  1. Absolute refractory period
    • The brief time interval following an action
    • potential when a neuron is incapable of being stimulated to fire another
    • impulse
  2. Acetylcholine
    • An excitatory neurotransmitter that operates at
    • synapses with muscles and is also the transmitter in some neural networks
    • involved in memory
  3. Action potential
    • A nerve impulse resulting from the
    • depolarization of an axon’s cell membrane
  4. Adrenal gland
    • Endocrine glands that release stress hormones, including
    • catecholamine and corticosteroids
  5. Agonist
    • A drug that increases or mimics the activity of
    • a neurotransmitter
  6. All or none law
    • state that an action potential is not
    • proportional to the intensity of simulation; either a neuron fires with maximum
    • intensity or it does not fire (compared with graded potential)
  7. Amygdala
    • A limbic system structure that helps organize emotional
    • response patterns
  8. Antagonist
    • A drug that inhibits or decreases the action of
    • a neurotransmitter
  9. Aphasia
    • The partial or total loss of ability to understand speech
    • (receptive aphasia) or to produce it (productive aphasia)
  10. Association cortex
    • The area of the cerebral cortex that do not have
    • sensory or motor functions but are involved in the integration of neural
    • activity that underlies perception, language, and other higher-ordeal mental
    • processes
  11. Autonomic nervous system
    • The branch of the peripheral nervous system that activates
    • the body’s involuntary muscles (e.g., heart) and internal organs
  12. Axon
    • An extension from one side of the neuron cell body that conducts
    • nerve impulses to other neurons, muscles, or glands
  13. Brain stem
    • The portion of the brain formed by the swelling of the
    • spinal cord as it enters the skull; its structures regulate basic survival
    • functions of the body, such as heart rate and respiration
  14. Broca’s area
    • A region of the left frontal lobe involved in
    • speech production
  15. Central nervous system
    • The portion of the nervous system that includes
    • the brain and the spinal cord
  16. Cerebellum
    • A convoluted hindbrain structure involved in motor
    • coordination and some aspects of learning and memory
  17. Cerebral cortex
    • The gray, convoluted outer covering of the brain that is the
    • seat of higher-order sensory, motor, perceptual, and mental processes
  18. Cerebrum
    • The most advanced part of the brain, containing the cerebral
    • cortex and underlying structures
  19. Computerized axial tomography (CT or CAT) scan
    • scan-A method of scanning the brain with narrow
    • beams of x rays that are then analyzed and combined by a computer to provide
    • pictures of brain structures from many different angles
  20. Corpus callosum
    • A broad brand of white, myelinated fibers that connects the
    • left and right cerebral hemispheres and allows the two hemispheres to
    • communicate with one another
  21. Dendrites
    • small branching fibers that extend from the soma of a neuron
    • and receive messages from adjacent neurons
  22. Electroencephalograph
    • A device used to record the simultaneous
    • activity of many thousands of neurons through electrodes attached to the scalp
  23. Endocrine system
    • The body’s system of glands that secrete hormones into the
    • bloodstream and thereby affect many bodily functions
  24. Forebrain
    • Brain structure above the midbrain, including
    • the thalamus, hypothalamus, limbic system, and the cerebral hemispheres;
    • involved in higher-order sensory, motor, and cognitive functions
  25. Functional MRI
    • A brain scanning procedure that produces pictures of blood
    • flow in the brain taken less than a second apart
  26. Graded potentials
    • A change in the electrical potential of a neuron that is
    • proportional to the intensity of the incoming stimulation but not sufficient to
    • produce an action potential
  27. Hindbrain
    • The part of the brain situated immediately above the spinal
    • cord that contains the brain stem and cerebellum
  28. Hippocampus
    • A structure of the limbic system that plays a key role in
    • the formation and storage of memories
  29. Homeostasis
    • the maintenance of biological equilibrium, or balance,
    • within the body
  30. Hormones
    • Chemical substances secreted by the glands of the endocrine
    • system that travels in the bloodstream and affect bodily organs, psychological
    • functions, and development
  31. Hypothalamus
    • A forebrain structure located below the thalamus and above
    • the pituitary gland that controls autonomic and hormonal processes and plays a
    • major role in many aspects of motivation and emotional behavior
  32. Interneurons
    • Neurons that are neither sensory nor motor neurons but that
    • perform associative or integrative function within the nervous system
  33. Lateralization
    • The degree of localization of a function in
    • either the right or the left cerebral hemisphere
  34. Limbic system
    • A group of subcortical structures, including the hippocampus
    • and amygdala, which are involved in organizing many goal-directed and emotional
    • behaviors
  35. Magnetic resonance imaging
    • A brain scanning procedure that produces a
    • highly detailed image of living tissue based on the tissue’s response to a
    • magnetic field; can be used to study both structure and, in the case of
    • functional MRI (fMRI), brain functions as they occur
  36. Medulla
    • A brain stem structure that controls vital functions,
    • including heartbeat and respiration
  37. Midbrain
    • Brain structure above the hindbrain that are involved in
    • sensory and motor functions and in attention and states of consciousness
  38. Motor cortex
    • The cortical area in the rear portion of the frontal lobes
    • that controls voluntary movements on the opposite sides of the body
  39. Motor neurons
    • specialized neurons that carry neural messages from the
    • brain and spinal cord to the muscles and glands
  40. Myelin sheath
    • A fatty insulating substance on the axon of some neurons
    • that increase the speed of neural transmission
  41. Neural plasticity
    • The ability of neurons to modify their structure and
    • function in response to experiential factors or injury
  42. Neural stem cell
    • Immature “uncommitted” cells that can mature into any type
    • of neuron or glial cell needed by the brain
  43. Neurogenesis
    • The production of new neurons in the nervous
    • system, sometimes to replace neurons that have died or been damaged
  44. Neuromodulators
    • neurotransmitter substances that are released by
    • neurons and circulate within the nervous system to affect the sensitivity of
    • many neurons to their natural transmitter substances
  45. Neurons
    • Nerve cells that constitute the basic building block of the
    • nervous system
  46. Neurotransmitters
    • Chemical substances that are released from the
    • axon of one neuron, travel across the synaptic space, and bind to specially
    • keyed receptors in another neuron, where they produce a chemical reaction that
    • is either excitatory or inhibitory
  47. Parasympathetic nervous system
    • The branch of the autonomic nervous system that slows down
    • bodily processes to conserve energy and reduce arousal
  48. Peripheral nervous system
    • All of the neurons that connect the central
    • nervous system with the sensory receptors, the muscles, and the glands
  49. Pons
    • A brain stem structure having sensory and motor tracts whose
    • functions are involved in sleep and dreaming
  50. Positron emission tomography scan
    • A procedure that provides a visual display of
    • the absorption of a radioactive substance by neurons, indicating how actively
    • they are involved as the brain performs a task
  51. Prefrontal cortex
    • The area of the frontal lobe just behind the eyes and
    • forehead that is involved in the executive functions of planning,
    • self-awareness, and responsibility
  52. Psychoactive drugs
    • Chemicals that produce alternations in
    • consciousness, emotion, and behavior
  53. Receptor sites
    • protein molecules on neurons’ dendrites or soma that are
    • specially shaped to accommodate a specific neurotransmitter molecule
  54. Resting potentials
    • the voltage differential between the inside and outside of a
    • neuron (above-70mv) caused by the unequal distribution of ions inside the
    • neuron’s membrane and outside in the fluid surrounding the neurons when the
    • neuron is at rest
  55. Reticular formation
    • -A structure extending from hindbrain into the lower
    • forebrain that plays a central role in consciousness, sleep and attention, in
    • part by alerting higher brain centers (ascending portion) and by selectively
    • blocking some inputs to higher regions in the brain (descending portion)
  56. Reuptake
    • The process whereby transmitter substances are
    • taken back into the presynaptic neuron so that they do not continue to
    • stimulate postsynaptic neurons
  57. Sensory neurons
    • specialized neurons that carry messages from the sense
    • organs to the spinal cord and brain
  58. Somatic nervous system
    • The branch of the peripheral nervous system that
    • provides inputs from the sensory receptors and outputs to the voluntary muscles
    • of the body
  59. Somatic sensory cortex
    • Cortical strips in the front portions of the
    • parietal lobes that receive sensory inputs from the opposite side of the body
  60. Sympathetic nervous system
    • The branch of the automatic nervous system that
    • has an arousal function on the bodily processes and mobilizing the body
  61. Synaptic space
    • The microscopic space between the axons of one
    • neuron and the dendrites or cell body of another over which the nerve impulse
    • transmitted v
  62. Synaptic vesicles
    • Chambers within the axon that contains the
    • neurotransmitter substance
  63. Thalamus
    • A major sensory integration and relay center in
    • the forebrain, sometimes referred to as the brain’s sensory switchboard
  64. Wernicke’s area
    • An area of the left temporal lobe that is
    • involved in the speech comprehension
Card Set
psychology ch 4
midterm 1