unit 3 Flashcards
biological psychology
the scientific study of the links between biological (genetic, neural, hormonal) and psychological processes
neuron
nerve cell; the basic building block of the nervous system
dendrites
a neuron’s bushy, branching extensions that receive messages and conduct impulses toward the cell body
axon
the neuron extension that passes messages through its branches to other neurons or to muscles or glands.
myelin sheath
fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next
action potential
a neural impulse; a brief electrical charge that travels down an axon.
refractory period
a period of inactivity after a neuron has fired. a resting period after orgasm, during which a man cannot achieve another
threshold
the level of stimulation required to trigger a neural impulse.
all or none response
a neuron’s reaction of either firing (with a full strength response) or not firing
synapse
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap or synaptic cleft
neurotransmitters
chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.
reuptake
a neurotransmitter’s reabsorption by the sending neuron.
endorphins
“morphine within”—natural, opiate-like neurotransmitters linked to pain control and to pleasure
agonist
a molecule that, by binding to a receptor site, stimulates a response
antagonist
a molecule that, by binding to a receptor site, inhibits or blocks a response
nervous system
the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.
central nervous system
the brain and spinal cord
peripheral nervous system
all those nerves that lie outside the brain and spinal cord
nerves
bundled axons that form neural “cables” connecting the central nervous system with muscles, glands, and sense organs.
sensory neurons
neurons that carry incoming information from the sensory receptors to the brain and spinal cord.
motor neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.
interneurons
neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs.
somatic nervous system
the division of the peripheral nervous system that controls the body’s skeletal muscles.
autonomic nervous system
the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms
parasympathetic nervous system
the division of the autonomic nervous system that calms the body, conserving its energy.
reflex
a simple, automatic response to a sensory stimulus, such as the knee-jerk response.
endocrine system
the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream
hormones
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.
adrenal glands
a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress
pituitary glands
the endocrine system’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands
lesion
tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue.
electroencephalogram
an amplified recording of the waves of electrical activity sweeping across the brain’s surface. These waves are measured by electrodes placed on the scalp
CT (computed tomography) scan
a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain’s structure.
PET (position emission tomography) scan
a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task
MRI (magnetic resonance imaging)
a technique that uses magnetic fields and radio waves to produce computer -generated images of soft tissue. MRI scans show brain anatomy.
brainstem
the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions
medulla
the base of the brainstem; controls heartbeat and breathing
thalamus
the brain’s sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla.
reticular formation
a nerve network that travels through the brainstem and thalamus and plays an important role in controlling arousal.
cerebellum
the “little brain” at the rear of the brainstem; functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory.
limbic system
neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives
amygdala
two lima-bean-sized neural clusters in the limbic system; linked to emotion
hypothalamus
neural structure lying below (hypo) the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward
cerebral cortex
the intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body’s ultimate control and information-processing center.
glial cells
cells in the nervous system that support, nour-ish, and protect neurons; they may also play a role in learning and thinking.
frontal lobes
portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments.
parietal lobes
portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position.
occipital lobes
portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields.
temporal lobes
portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear.
somatosensory cortex
area at the front of the parietal lobes that registers and processes body touch and movement sensations.
association areas
areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking.
plasticity
the brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience.
neurogenesis
the formation of new neurons
corpus callosum
the large band of neural fibers connecting the two brain hemispheres and carrying messages between them
split brain
a condition resulting from surgery that isolates the brain’s two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them
consciousness
our awareness of ourselves and our environment.
cognitive neuroscience
the interdisciplinary study of the brain activity linked with cognition (including perception, thinking, mem-ory, and language)
dual processing
the principle that information is often simultaneously processed on separate conscious and unconscious tracks.
behavior genetics
the study of the relative power and limits of genetic and environmental influences on behavior
enviroment
every external influence, from prenatal nutrition to the people and things around us.
chromosomes
threadlike structures made of DNA molecules that contain the genes.
DNA
a complex molecule containing the genetic information that makes up the chromosomes.
genes
the biochemical units of heredity that make up the chromosomes; segments of DNA capable of synthesizing proteins
genome
the complete instructions for making an organism, consisting of all the genetic material in that organism’s chromosomes
identical twins
twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms.
fraternal twins
twins who develop from separate fertilized eggs. They are genetically no closer than brothers and sisters, but they share a fetal environment.
molecular genetics
the subfield of biology that studies the molecular structure and function of genes.
heritability
the proportion of variation among individuals that we can attribute to genes. The heritability of a trait may vary, depending on the range of populations and environments studied.
interaction
the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)
epigenetics
the study of environmental influences on gene expression that occur without a DNA change
evolutionary psychology
the study of the evolution of behavior and the mind, using principles of natural selection.
natural selection
the principle that, among the range of inherited trait variations, those contributing to reproduction and survival will most likely be passed on to succeeding generations
mutation
a random error in gene replication that leads to a change.
acetylcholine
a neurotransmitter involved in learning, memory and muscle contraction
dopamine
neurotransmitter involved in mood, movement, attention, learning
norepinephrine
neurotransmitter important in controlling alertness, wakefulness, mood, and attention
serotonin
neurotransmitter that regulates sleep, mood, appetite and body temp
glutamate
the main excitatory neurotransmitter in the central nervous system, important for learning and memory
GABA
the primary neurotransmitter in the nervous system
endorphins
neurotransmitters linked to reduce pain and increased pleasure
paul broca
discovered broca’s area which controls language expression
karl wernicke
discovered area of left temporal lobe that involved language understanding, person damaged in this area uses correct words but they don’t make sense
roger sperry
studied split brain patterns; showed that left/right hemispheres have different functions
Michael gazzaniga
studied of the neural basis of mind with primary responsibility for initiating human split-brain research
charles darwin
english natural scientist who formulated a theory of evolution by natural selection