45 terms

The Brain

flashcards about the human brain and neural communication
cell body of a neuron
branching extensions of neuron that receives messages from neighboring neurons
long single extension of a neuron covered with the myelin sheath to insulate and speed up messages through neurons
terminal branches
lie at the end of axons; form junctions with other cells
action potential
a neural impulse; a brief electrical charge that travels down an axon
the junction between two neurons (axon-to-dendrite) or between a neuron and a muscle
(biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction
chemicals produced by the body during times of physical or psychological stress
stops hormones from fitting into the receptor sites and blocks the receptor
sensory neurons
neurons that carry incoming information from the sense receptors to the central nervous system
motor neurons
neurons that carry outgoing information from the central nervous system to the muscles and glands
Central nervous system neurons that internally communicate and intervene between the sensory inputs and motor outputs
chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another
pituitary gland
the master gland of the endocrine system
sensory switchboard, message center
a band of nerve fibers linking the medulla oblongata and the cerebellum with the midbrain
reticular formation
a complex neural network in the central core of the brainstem
the base of the brainstem; controls heartbeat and breathing
the "little brain" attached to the rear of the brainstem; its functions include processing sensory input and coordinating movement output and balance
limbic system
a doughnut-shaped system of neural structures at the border of the brainstem and cerebral hemispheres; associated with emotions such as fear and aggression and drives such as those for food and sex. Includes the hippocampus, amygdala, and hypothalamus.
two almond-shaped neural clusters that are components of the limbic system and are linked to emotion
brain structure that acts as a control center for recognition and analysis of hunger, thirst, fatigue, anger and body temperature
cerebral cortex
the intricate fabric of interconnected neural cells that covers the cerebral hemispheres; the body's ultimate control and information-processing center
frontal lobe
The lobe at the front of the brain associated with movement, speech, and impulsive behavior.
parietal lobe
portion posterior to the frontal lobe, responsible for sensations such as pain, temperature, and touch
temporal lobe
portion that lies below the frontal lobe, responsible for hearing, taste, and smell
occipital lobe
portion posterior to the parietal and temporal lobes, responsible for vision
visual function
complex processing of visual info, occipital lobe
auditory function
complex processing of auditory info, temporal lobe
a neurotransmitter found in the brain, spinal chord, and parts of the PNS, responsible for muscle contraction
neurotransmitter that influences voluntary movement, attention, alertness; lack of dopamine linked with Parkinson's disease; too much is linked with schizophrenia
a neurotransmitter that affects hunger,sleep,arousal,and mood. appears in lower than normal levels in depressed persons
a neurotransmitter's reabsorption by the sending neuron
gamma-aminobutryic acid
major inhibitory neurotransmitters, helps control anxiety and stress
inhibits the firing of neurons in the central nervous system, but excites the heart muscle, intestines and urogenital tract
rational impulse
we try to force what we see to make sense even when it doesn't
absolute threshold
the minimum stimulation needed to detect a particular stimulus 50 percent of the time
difference threshold
the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference
sensory adaptation
diminished sensitivity as a consequence of constant stimulation
subliminal message
a stimulus that is presented below the threshold for awareness
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond
retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.
bottom-up processing
analysis that begins with the sensory receptors and works up to the brain's integration of sensory information
tri-chromatic theory
three different retinal receptors one picks up red, one green, one blue. Theory by Helmholtz and Young. All 3 colors make up the base of other colors.
opponent-processing theory
Herings theory that color perception is based on three systems of color opposites blue-yellow, red-green, and black-white