state of the neuron when not firing a neural impulse
the release of the neural impulse consisting of a reversal of the electrical charge within the axon, also allows +Na ions to enter the cell
referring to the fact that a neuron either fires completely or does not fire at all
branches at the end of the axon
rounded areas on the end of axon terminals
sack-like structures found inside the synaptic knob containing chemicals
chemical found in the synaptic vesicles which, when released, has an effect on the next cell
memory & movement
mood, sleep, appetite
major inhibitory neurotransmitter, sleep and movement
mood and arousel (alertness/awakeness)
sensations of pleasure
referring to the fact that a neuron either fires completely or does not fire at all
holes in the surface of the dendrites or certain cells of the muscles and glands, which are shaped to fit only certain neurotransmitters
neurotransmitter that causes the receiving cell to fire
neurotransmitter that causes the receiving cell to stop firing
mimic or enhance the effects of a neurotransmitter on the receptor sites of the next cell, increasing or decreasing the activity of that cell
block or reduce a cell's response to the action of other chemicals or neurotransmitters
process by which neurotransmitters are taken back into the synaptic vesicles
a complex protein that is manufactured by cells
Central nervous system (CNS)
part of the nervous system consisting of the brain and spinal cord
a long bundle of neurons that carries messages to and from the body to the brain that is responsible for very fast, lifesaving reflexes
a neuron that carries information from the senses to the central nervous system. Also called afferent neuron
a neuron that carries messages from the central nervous system to the muscles of the body. Also called efferent neuron
a neuron found in the center of the spinal cord that receives information from the sensory neurons and sends commands to the muscles through the motor neurons
the ability to constantly change both the structure and function of cell involved in trauma
peripheral nervous system (PNS)
all nerves and neurons that are not contained in the brain and spinal cord but that run through the body itself. Divided into somatic and autonomic nervous system
somatic nervous system
division of the PNS consisting of nerves that carry information from the senses to the CNS and from the CNS to the voluntary muscles of the body
nerves coming from the sensory organs to the CNS consisting of sensory neurons
nerves coming from the CNS to the voluntary muscles, consisting of motor neurons
autonomic nervous system (ANS)
division of the PNS consisting of nerves that control all of the involuntary muscles, organs, and glands sensory pathway nerves coming from the sensory organs to the CNS consisting of sensory neurons
fight-or-flight system - part of the ANS that is responsible for reacting to stressful events and bodily arousal.
part of the ANS that restores the body to normal functioning after arousal and is responsible for the day-to-day functioning of the organs and glands
insertion of a thin, insulated wire into the brain through which an electrical current is sent that destroys the brain cells at the tip of the wire
electrical stimulation of the brain (ESB)
milder electrical current that causes neurons to react as if they had received a message
machine designed to record the brain wave patterns produced by electrical activity of the surface of the brain
computed tomography (CT)
brain-imaging method using computer controlled X-rays of the brain
magnetic resonance imaging (MRI)
brain-imaging method using radio waves and magnetic fields of the body to produce detailed images of the brain
computer makes a sort of "movie" of changes in the activity of the brain using images from different time periods
positron emission tomography (PET)
brain-imaging method in which a radioactive sugar is injected into the subject and a computer compiles a color-coded image of the activity of the brain with lighter colors indicating more activity
medulla, pons, RF, cerebellum
the first large swelling at the top of the spinal cord, forming the lowest part of the brain, which is responsible for life-sustaining functions such as breathing, swallowing, and heart rate
the larger swelling above the medulla that connects the top of the brain to the bottom and that plays a part in sleep, dreaming, left-right body coordination, and arousal
reticular formation (RF)
an area of neurons running through the middle of the medulla and the pons and slightly beyond that is responsible for selective attention
part of the lower brain located behind the pons that controls and coordinates involuntary, rapid, fine motor movement
structures under the cortex
limbic system (thalamus, olfactory bulbs, hypothalamus, hippocampus, amygdala
a group of several brain structures located under the cortex and involved in learning, emotion, memory, and motivation
part of the limbic system located in the center of the brain, this structure relays sensory information from the lower part of the brain to the proper areas of the cortex and processes some sensory information before sending it to its proper area
two projections just under the front of the brain that receive information from the receptors in the nose located just below
small structure in the brain located below the thalamus and directly above the pituitary gland, responsible for motivational behavior such as sleep, hunger, thirst, and sex. Sits above and controls the pituitary gland (master endocrine gland)
curved structure located within each temporal lobe, responsible for the formation of long-term memories and the storage of memory for location of objects
brain structure located near the hippocampus, responsible for fear responses and memory of fear
outermost covering of the brain consisting of densely packed neurons, responsible for higher thought processes and interpretation of sensory input
wrinkling of the cortex. Allows a much larger area of cortical cells to exist in the small space inside the skull
the two sections of the cortex on the left and right sides of the brain
thick band of neurons that connects the right and left cerebral hemispheres
4 lobes of the brain
occipital, parietal, temporal, frontal
section of the brain located at the rear and bottom of each cerebral hemisphere containing the visual centers of the brain
primary visual cortex
processes visual information from the eyes
visual association cortex
identifies and makes sense of visual information
sections of the brain located at the top and back of each cerebral hemisphere containing the centers for touch, taste, and temperature sensations
area of neurons running down the front of the parietal lobes responsible for processing information from the skin and internal body receptors for touch, temperature, body position, and possibly taste
areas of the cortex located just behind the temples containing the neurons responsible for the sense of hearing and meaningful speech
primary auditory cortex
processes auditory information from the ears
auditory association cortex
identifies and makes sense of auditory information
areas of the cortex located in the front and top of the brain, responsible for higher mental processes and decision making as well as the production of fluent speech
section of the frontal lobe located at the back, responsible for sending motor commands to the muscles of the somatic nervous system
areas within each lobe of the cortex responsible for the coordination and interpretation of information, as well as higher mental processing
condition resulting from damage to Broca's area (usually in left frontal lobe), causing the affected person to be unable to speak fluently, to mispronounce words, and to speak haltingly
condition resulting from damage to Wernicke's area (usually in left temporal lobe), causing the affected person to be unable to understand or produce meaningful language
condition produced by damage to the association areas of the right hemisphere resulting in an inability to recognize objects or body parts in the left visual field
the upper part of the brain consisting of the two hemispheres and the structures that connect them
split brain research
Study of patients with severed corpus callosum. Involves sending messages to only one side of the brain. Demonstrates right and left brain specialization
left side of brain
seems to control language, writing, logical thought, analysis, and mathematical abilities, processes information sequentially, can speak
right side of brain
controls emotional expression, spatial perception, recognition of faces, patterns, melodies, and emotions, processes information globally, cannot speak
glands that secrete chemicals called hormones directly into the bloodstream
chemicals released into the bloodstream by endocrine glands
gland located in the brain that secretes human growth hormone and influences all other hormone-secreting glands (also known as the master gland)
endocrine gland located near the base of the cerebrum that secretes melatonin
endocrine gland found in the neck that regulates metabolism
endocrine gland that controls the levels of sugar in the blood
the sex glands that secrete hormones that regulate sexual development and behavior as well as reproduction
the female gonads
the male gonads
endocrine glands located on top of each kidney that secrete over 30 different hormones to deal with stress, regulate salt intake, and provide a secondary source of sex hormones affecting the sexual changes that occur during adolescence
the activation of receptors in the various sense organs
specialized forms of neurons
just noticeable difference (JND)
the smallest difference between two stimuli that is detectable 50 percent of the time
the smallest amount of energy needed for a person to consciously detect a stimulus 50 percent of the time it is present
stimuli that are below the level of conscious awareness. Just strong enough to activate the sensory receptors but not strong enough for people to be consciously aware of them
"below the threshold."
process by why subliminal stimuli act upon the unconscious mind, influencing behavior
tendency of the brain to stop attending to constant, unchanging information
tendency of sensory receptor cells to become less responsive to a stimulus that is unchanging
constant movement of the eyes, tiny little vibrations called that people do not notice consciously; prevents sensory adaptation to visual stimuli.
determined by the amplitude of the wave—how high or how low the wave actually is. The higher the wave, the brighter the light will be. Low waves are dimmer.
or hue, is determined by the length of the wave
the portion of the whole spectrum of light that is visible to the human eye
refers to the purity of the color people see; mixing in black or gray would also lessen the saturation
clear membrane that covers the surface of the eye; protects the eye and is the structure that focuses most of the light coming into the eye
vision-improving technique that uses this fact by making small incisions in the cornea to change the focus in the eye
next visual layer; clear, watery fluid that is continually replenished and supplies nourishment to the eye
hole through which light from the visual image enters the interior of the eye
round muscle (the colored part of the eye) in which the pupil is located; can change the size of the pupil, letting more or less light into the eye; helps focus the image
another clear structure behind the iris, suspended by muscles; finishes the focusing process begun by the cornea
the change in the thickness of the lens as the eye focuses on objects that are far away or close
jelly-like fluid called that also nourishes the eye and gives it shape
final stop for light in the eye. Contains 3 layers: Ganglion cells, Bipolar cells, Photoreceptors that respond to various light waves
visual sensory receptors found at the back of the retina, responsible for noncolor sensitivity to low levels of light
visual sensory receptors found at the back of the retina, responsible for color vision and sharpness of vision
area in the retina where the axons of the three layers of retinal cells exit the eye to form the optic nerve, insensitive to light
the recovery of the eye's sensitivity to visual stimuli in darkness after exposure to bright lights. Night blindness
the recovery of the eye's sensitivity to visual stimuli in light after exposure to darkness.
theory of color vision that proposes three types of cones: red, blue, and green.
images that occur when a visual sensation persists for a brief time even after the original stimulus is removed
theory of color vision that proposes four primary colors with cones arranged in pairs: red and green, blue and yellow. Lateral geniculate nucleus (LGN) of thalamus
either have no cones or have cones that are not working at all.
either the red or the green cones are not working.
interpreted as frequency or pitch (high, medium, or low).
interpreted as volume (how soft or loud a sound is).
interpreted as timbre (a richness in the tone of the sound).
cycles or waves per second, a measurement of frequency.
short tunnel that runs from the pinna to the eardrum (tympanic membrane).
thin section of skin that tightly covers the opening into the middle part of the ear, just like a drum skin covers the opening in a drum. When sound waves hit the eardrum, it vibrates and causes three tiny bones in the middle ear to vibrate. Hammer, Anvil, Stirrup
snail-shaped structure of the inner ear that is filled with fluid.
organ of corti
rests in the basilar membrane; contains receptor cells for sense of hearing.
bundle of axons from the hair cells in the inner ear; receives neural message from the organ of Corti.
psychological experience of sound that corresponds to the frequency of the sound waves; higher frequencies are perceived as higher pitches.
theory of pitch that states that different pitches are experienced by the stimulation of hair cells in different locations on the organ of Corti.
theory of pitch that states that pitch is related to the speed of vibrations in the basilar membrane volley principle theory of pitch that states that frequencies above 100 Hz cause the hair cells (auditory neurons) to fire in a volley pattern, or take turns in firing.
conducting hearing impairment
an result from either: damaged eardrum (which would prevent sound waves from being carried into the middle ear properly), or damage to the bones of the middle ear (sounds cannot be conducted from the eardrum to the cochlea).
nerve hearing impairment
can result from either: damage in the inner ear, or damage in the auditory pathways and cortical areas of the brain.
a microphone implanted just behind the ear picks up sound from the surrounding environment. Speech processor selects and arranges the sound picked up by the microphone. Implant is a transmitter and receiver, converting signals into electrical impulses. Collected by the electrode array in the cochlea and then sent to the brain.
taste receptor cells in mouth; responsible for sense of taste
the sensation of a taste
five basic tastes
sweet sour salty bitter "Brothy"
sense of smell.
areas of the brain located just above the sinus cavity and just below the frontal lobes that receive information from the olfactory receptor cells. At least 1,000 olfactory receptors.
the body senses consisting of the skin senses, the kinesthetic sense, and the vestibular senses
the sensations of touch, pressure, temperature, and pain. Sensory receptors in the skin
pain signals must pass through a "gate" located in the spinal cord.
sense of the location of body parts in relation to the ground and each other. Proprioceptive receptors (proprioceptors)
the sensations of movement, balance, and body position sensory conflict theory an explanation of motion sickness in which the information from the eyes conflicts with the information from the vestibular senses, resulting in dizziness, nausea, and other physical discomforts.