Unit 2 pt 1 Flashcards
A nerve cell; basic building block of the nervous system
neuron
Part of the neuron that contains the nucleus; the cells life support center
cell body
Neurons often bushy, branching extensions that recieve and integrate messages, conducting impulses towards the cell body
dendrites
electrical wire that carries a signal sent from the nucleus
axon
a fatty tissue layer segmentally encasing the axon of some neurons; enables vastly greater transmission
myelin sheath
cells in the nervous system that support, nourish, and protect neurons
glial cells
a neural impulse; a brief electrical charge that travels down an axon
action potential
the level of stimulation required to trigger a neural impulse
threshold
a period of inactivity after a neuron has fired
refractory period
a neuron’s reaction of either firing (with a full-strength 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
synapse
chemical messengers that cross the synaptic gaps between neurons
neurotransmitters
a neurotransmitter’s reabsorption by the sending neuron
reuptake
“morphine within”–natural, opiatelike neurotransmitters linked to pain control and to pleasure.
endorphins
a molecule that, by binding to a receptor site, stimulates a response
agonist
the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
nervous system
brain and spinal cord
central nervous system
the sensory and motor neurons that connect the CNS to the rest of the body
peripheral nervous system
bundled axons that form neural “cables” connecting the central nervous system with muscles, glands, and sense organs
nerves
neurons that carry incoming information from the sensory receptors to the brain and spinal cord
sensory neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
motor neurons
neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs
interneurons
the division of the peripheral nervous system that controls the body’s skeletal muscles
somatic nervous system
the part of the nervous system responsible for control of the bodily functions not consciously directed, such as breathing, the heartbeat, and digestive processes.
autonomic nervous system
the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations
sympathetic nervous system
the division of the autonomic nervous system that calms the body, conserving its energy
parasympathetic nervous system
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
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
hormones
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
The endocrine system’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.
pituitary gland
An amplified recording of the waves of electrical activity that sweep across the brain’s surface. These waves are measured by electrodes placed on the scalp.
EEG
a brain imaging technique that measures magnetic fields from the brain’s natural electrical activity
MEG
a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body
CT scan
a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task
PET scan
a technique that uses magnetic fields and radio waves to produce computer-generated images that distinguish among different types of soft tissue; allows us to see structures within the brain
MRI
A technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans.
fMRI
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
the base of the brainstem; controls heartbeat and breathing
medulla
the brain’s sensory switchboard, 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
a nerve network that travels through the brainstem and thalamus and plays an important role in controlling arousal
reticular formation
the “little brain” at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance
cerebellum
neural system located below the cerebral hemispheres; associated with emotions and drives
limbic system
two lima bean-sized neural clusters in the limbic system; linked to emotion.
amygdala
A neural structure lying below 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
A neural center located in the limbic system that helps process explicit memories for storage.
hippocampus
Fabric of interconnected neuron cells. Higher order thinking. Takes meaning and puts it to focus. 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 judgements
frontal lobe
portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position
parental lobe
portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields
occipital lobe
portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear
temporal lobe
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
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 brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience
plasticity
the formation of new neurons
neurogenesis
the large band of neural fibers connecting the two brain hemispheres and carrying messages between them
corpus callosum
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
our awareness of ourselves and our environment
consciousness
study of the physical changes in the brain and nervous system during thinking
cognitive neuroscience
the principle that information is often simultaneously processed on separate conscious and unconscious tracks
dual processing
a condition in which a person can respond to a visual stimulus without consciously experiencing it
blindsight
the processing of many aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions, including vision. Contrasts with the step-by-step (serial) processing of most computers and of conscious problem solving.
parallel processing
the processing of one aspect of a problem at a time; used when we focus attention on new or complex tasks
sequential processing
the study of the relative power and limits of genetic and environmental influences on behavior
behavior genetics
the genetic transfer of characteristics from parents to offspring
heredity
every nongenetic 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
the biochemical units of heredity that make up the chromosomes; a segment of DNA capable of synthesizing a protein
genes
the complete instructions for making an organism, consisting of all the genetic material in that organism’s chromosomes
genome
Twins who develop from separate eggs. They are genetically no closer than brothers and sisters, but they share a fetal environment
fraternal twins
twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms
identical environment
the passing of genetic traits from parent to offspring
heredity
the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)
interaction
the subfield of biology that studies the molecular structure and function of genes
molecular genetics
the study of how the structure and function of genes interact with our environment to influence behavior
molecular behavioral genetics
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
culturally modeled guide for how to act in various situations
social script
a molecule that inhibits or blocks a neurotransmitter’s action
anatagonist
tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue
lesion
