VOCAB Flashcards
The Study of the relative power and limits of genetics and environmental influences and behavior
Behavioral Genetics
every external influence, from prenatal nutrition to the people and things around us.
Environment
threadlike structures made of DNA molecules that contain the genes
Chromosomes
a complex molecule containing the
genetic information that makes up
the chromosomes.
DNA (deoxyribonucleic acid)
the biochemical units
of heredity that make up the
chromosomes; segments of DNA
capable of synthesizing proteins.
Genes
the complete instructions
for making an organism, consisting
of all the genetic material in that
organism’s chromosomes.
Genome
twins who develop from
a single fertilized egg that splits
in two, creating two genetically
identical organisms
Identical twins (Monozygotic twins)
twins who develop from separate
fertilized eggs. They are genetically
no closer than brothers and sisters,
but they share a fetal environment.
Fraternal twins (dizygotic twins)
the subfield of biology that studies the
molecular structure and function
of genes.
Molecular genetics
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.
Heritability
the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity).
Interaction
the study of environmental influences on gene expression that occur without a
DNA change
Epigenetics
the study of the evolution of behavior
and the mind, using principles of
natural selection.
Evolutionary psychology
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.
Natural Selection
A random error in gene replication that leads to a change
Mutation
the scientific study of the links
between biological (genetic, neural,
hormonal) and psychological
processes. (Some biological
psychologists call themselves
behavioral neuroscientists,
neuropsychologists, behavior
geneticists, physiological psychologists,
or biopsychologists.)
Biological Psychology
a nerve cell; the basic
building block of the nervous
system.
Neuron
a neuron’s bushy,
branching extensions that receive
messages and conduct impulses
toward the cell body.
Dendrites
the neuron extension that
passes messages through its
branches to other neurons or to
muscles or glands.
Axon
a fatty tissue layer segmentally encasing
the axons of some neurons; enables
vastly greater transmission speed
as neural impulses hop from one
sausage-like node to the next
Myelin sheath
a neural impulse;
a brief electrical charge that travels
down an axon.
Action potential
a period of inactivity after a neuron has fired
Refractory period
the level of stimulation
required to trigger a neural impulse.
Threshold
a neuron’s reaction of either firing (with a fullstrength response) or not firing
All-or-none response
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.
Synapse
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
Neurotransmitters
a neurotransmitter’s
reabsorption by the sending neuron.
Reuptake
“morphine within”—natural,
opiate-like neurotransmitters linked
to pain control and to pleasure.
Endorphins
a molecule that, by
binding to a receptor site, stimulates
a response.
Agonist
a molecule that, by
binding to a receptor site, inhibits
or blocks a response.
Antagonist
neurons within
the brain and spinal cord that
communicate internally and
intervene between the sensory
inputs and motor outputs.
Interneurons
bundled axons that
form neural “cables” connecting
the central nervous system with
muscles, glands, and sense organs
nerves
the division of the
autonomic nervous system that
calms the body, conserving its energy.
Parasympathetic nervous system
the body’s
speedy, electrochemical
communication network, consisting
of all the nerve cells of the peripheral
and central nervous systems.
Nervous system
neurons that carry incoming
information from the sensory
receptors to the brain and spinal cord
Sensory (afferent) neurons
the sensory and motor
neurons that connect the central
nervous system (CNS) to the rest of
the body.
Peripheral nervous system (PNS)
the division of the autonomic
nervous system that arouses the
body, mobilizing its energy in
stressful situations.
Sympathetic 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.
Autonomic nervous system (ANS)
neurons
that carry outgoing information
from the brain and spinal cord to the
muscles and glands.
Motor (efferent) neurons
The brain and the spinal cord
central nervous system (CNS)
a simple, automatic
response to a sensory stimulus,
such as the knee-jerk response.
Reflex
the body’s “slow” chemical
communication system; a set of
glands that secrete hormones into
the bloodstream.
Endocrine system
the
division of the peripheral nervous
system that controls the body’s
skeletal muscles. Also called the
skeletal nervous system
Somatic nervous system
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.
Adrenal glands
chemical messengers
that are manufactured by the
endocrine glands travel through the
bloodstream and affect other tissues.
Hormones
tissue destruction. A brain lesion is a
naturally or experimentally caused
destruction of brain tissue.
Lesion
the endocrine
system’s most influential gland.
Under the influence of the
hypothalamus, the pituitary
regulates growth and controls other
endocrine glands.
Pituitary glands
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. (Also called
CAT scan.)
CT (computed tomography) scan (CAT scan)
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.
(EEG) Electroencephalogram
a visual display of brain activity that detects
where a radioactive form of glucose
goes while the brain performs a
given task.
PET (positron emission
tomography) scan
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
Brainstem
a technique that uses
magnetic fields and radio waves
to produce computer-generated
images of soft tissue. MRI scans
show brain anatomy.
MRI (magnetic resonance imaging)
a
technique for revealing blood flow
and, therefore, brain activity by
comparing successive MRI scans.
fMRI scans show brain function as
well as its structure.
fMRI (functional MRI)
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.
Cerebellum
the base of the brainstem; controls heartbeat and breathing.
Medulla
a nerve network that travels through the
brainstem and thalamus and plays
an important role in controlling
arousal.
Reticular formation
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.
Thalamus
two lima-bean-sized neural clusters in
the limbic system; linked to emotion.
Amygdala
neural system (including the hippocampus,
amygdala, and hypothalamus)
located below the cerebral
hemispheres; associated with
emotions and drives.
Limbic system
a 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.
Hypothalamus
the intricate fabric of interconnected
neural cells covering the cerebral
hemispheres; the body’s ultimate
control and information-processing
center.
Cerebral cortex
portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making
plans and judgments.
Frontal Lobes
cells in the nervous system that support,
nourish, and protect neurons; they
may also play a role in learning and
thinking.
Glial cells
portion of the cerebral cortex lying
at the top of the head and toward
the rear; receives sensory input for
touch and body position.
Parietal Lobes
portion of the cerebral cortex lying
at the back of the head; includes
areas that receive information from
the visual fields
Occipital Lobes
portion of the cerebral cortex lying roughly above the ears; includes the auditory
areas, each receiving information
primarily from the opposite ear.
temporal lobes
an area at the rear
of the frontal lobes that controls
voluntary movements.
Motor cortex
area at the front of the parietal lobes that
registers and processes body touch
and movement sensations.
Somatosensory cortex
the brain’s ability to change, especially during childhood, by reorganizing after
damage or by building new
pathways based on experience.
Plasticity
a condition resulting from surgery that isolates the brain’s two hemispheres by cutting the fibers (mainly those of the corpus
callosum) connecting them.
Split Brain
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.
Association areas
the large band of neural fibers connecting the two brain hemispheres and carrying
messages between them.
Corpus callosum
the formation of new neurons.
neurogenesis
