central nervous system
consists of the brain and spinal cord and coordinates all of the body's activities
peripheral nervous system
the sensory and motor neurons that connect the CNS to the rest of the body
dendrite
the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body
soma
cell body
axon
the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands
neuron
a nerve cell; the basic building block of the nervous system
function of a neuron
process and transmit information
hormones
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
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
DNA segments that serve as the key functional units in hereditary transmission.
natural selection
A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
mutations
Random errors in gene replication that lead to a change in the sequence of nucleotides. The source of all genetic diversity.
behavior genetics
the study of the relative power and limits of genetic and environmental influences on behavior
twin studies
a common method of investigating whether nature or nurture affects behavior
klinefelters
trisomy of sex chromosome, XXY, results from two or more X chromosome in males
down syndrome
3rd copy of chromosome 21
Turner Syndrome
A chromosomal disorder in females in which either an X chromosome is missing, making the person XO instead of XX, or part of one X chromosome is deleted.
endocrine system
the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream
pineal gland
secretes melatonin
pituitary gland
The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.
adrenal gland
A pair of endocrine glands that sit just above the kidneys and secrete hormones that help arouse the body in times of stress.
hypothalamus
keeps your body stable and in homeostasus
spinal reflex
A simple automatic action of the spinal cord not requiring involvement of the brain, such as the knee-jerk reflex
somatic nervous system
Division of the PNS that controls the body's skeletal muscles.
sympathetic nervous system
fight or flight
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
a set of nerves that helps the body return to a normal resting state
Endorphins
"morphine within"--natural, opiatelike neurotransmitters linked to pain control and to pleasure.
excititory neurotransmitters
excite a neuron; cause a response
action potential
a neural impulse; a brief electrical charge that travels down an axon
excess dopamine
schizophrenia
lack of dopamine
Parkinson's disease
inhibitory neurotransmitters
inhibit a neuron; decrease a response
parapelgia
paralysis of both legs and the lower part of the body
quadripelgia
paralysis of all four limbs
afferent neuron
nerve cell that sends messages to brain or spinal cord from other parts of the body; also called sensory neurons
efferent neurons
neurons that take information from the brain to the rest of the body
agonist
a molecule that increases a neurotransmitter's action
antagonist
occupy a receptor site to block a neurotransmitter
depolarization
The process during the action potential when sodium is rushing into the cell causing the interior to become more positive; -55
repolarization
Return of the cell to resting state, caused by reentry of potassium into the cell while sodium exits the cell; -70
all or none law
principle that the action potential in a neuron does not vary in strength; the neuron either fires at full strength or it does not fire at all
membrane potential
voltage across a membrane
myelin sheath
covers the axon of some neurons and helps speed neural impulses
nodes of ranvier
a gap in the myelin sheath of a nerve, between adjacent Schwann cells.
schwann cells
produce myelin in PNS
stimulus threshold
the minimum level of stimulation required to activate a particular neuron
resting potential
the state of the neuron when not firing a neural impulse
synapse
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron
reuptake
process by which neurotransmitters are taken back into the synaptic vesicles
dopamine
influences movement, learning, attention, and emotion
serotonin
regulates mood
Norepinephrine
helps control alertness and arousal
gaba
a major inhibitory neurotransmitter
acetycholine
enables muscle action, learning, and memory
glutamate
A major excitatory neurotransmitter; involved in memory
hierarchical organization of the brain
hindbrain-->midbrain-->forebrain
hindbrain
medulla, pons, cerebellum, reticular formation
midbrain
A small part of the brain above the pons that integrates sensory information and relays it upward.
Forebrain (cerebral cortex)
Collection of upper-level brain structures, including the thalamus, hypothalamus, and limbic system.
cerebral cortex
The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center.
left hemisphere
controls the right side of the body; analytical, language, math
right hemisphere
controls the left side of the body; creative, intuitive, spacial
occipital lobe
vision; wired backwards
medulla
the base of the brainstem; controls heartbeat and breathing
pons
A brain structure that relays information from the cerebellum to the rest of the brain
Cerebellum
Balance and coordination
reticular formation
a nerve network in the brainstem that plays an important role in controlling arousal
basal ganglia
structures in the forebrain that help to control movement
gray matter
Brain and spinal cord tissue that appears gray with the naked eye; consists mainly of neuronal cell bodies (nuclei) and lacks myelinated axons.
corpus callosum
the large band of neural fibers connecting the two brain hemispheres and carrying messages between them
temporal lobe
An area on each hemisphere of the cerebral cortex near the temples that is the primary receiving area for auditory information
pariental lobe
processes information about touch; creates 3d spacial awarness
frontal lobe
A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement
long-term potentiation
an increase in a synapse's firing potential after brief, rapid stimulation. Believed to be a neural basis for learning and memory.
Hippocampus
A neural center located in the limbic system that helps process explicit memories for storage.
the limbic system
neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives.
Thalamus
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
Hypothalamus
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.
Amygdala
processes fear and threatening stimuli; linked to emotion.
prefrontal cortex
involved in impulse control and long term planning; not fully developed until 25
cortical areas
Thinking, memory and language are the last to develop. Mental abilities surge-Fiber pathways supporting language and agility.
somatosensory cortex
registers and processes body touch and movement sensations
motor cortex
an area at the rear of the frontal lobes that controls voluntary movements
brocas area
Controls language expression - an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved in speech.
Wernicke's area
controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe
roger sperry
scientist who won a Nobel Prize for work with split brain patients; theorized that the hemispheres could operate independently of each other.
cortical localization
notion that different functions are located in different areas of the brain
Michael Gazzaniga
Conducted the "HE-ART" experiments with split brain patients
lateralization of function
the tendency for some neural functions or cognitive processes to be specialized to one side of the brain or the other. Sometimes called "hemispheric specialization" or "hemispheric lateralization".
structural plasticity
The brain's ability to actually change its physical structure (as a result of learning).
functional plasticity
The brain's ability to move functions from a damaged area of the brain to other undamaged areas.
lesion
tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue
Epigenetics
is the study of how the environment and other factors can change the way that genes are expressed.
blood-brain barrier
Blood vessels (capillaries) that selectively let certain substances enter the brain tissue and keep other substances out
neurogenesis
the strengthening and development of neural tissue
neurogenesis rats
Group I involved rats both raised in isolation, and with no toys to stimulate their brain.
Group II rats was raised in small groups, and was given toys to play with.
Findings: rats in Group II had heavier forebrains - stimulation caused long term potentiation/neurogenesis, which made their brains weigh discernably more.