AP Psychology Chapter 4 Vocab

central nervous system

central nervous system

the portion of the nervous system consisting of the brain and spinal cord

spinal cord

a collection of neurons and supportive tissue running from the base of the brain down the center of the back, protected by a column of bones (the spinal column)

spinal reflexes

automatic behaviors produced by the spinal cord without brain involvement

peripheral nervous system

all portions of the nervous system outside the brain and spinal cord; it includes sensory and motor nerves

somatic nervous system

the subdivision of the peripheral nervous system that connects to sensory receptors and to skeletal muscles; sometimes called the skeletal nervous system

autonomic nervous system

the subdivision of the peripheral nervous system that regulates the internal organs and glands

sympathetic nervous system

the subdivision of the autonomic nervous system that mobilizes bodily resources and increases the output of energy during emotion and stress

parasympathetic nervous system

the subdivision of the autonomic nervous system that operates during relaxed states and that conserves energy

neuron

a cell that conducts electrochemical signals; the basic unit of the nervous system; also called a nerve cell

glia

cells that support, nurture, and insulate neurons, remove debris when neurons die, enhance the formation and maintenance of neural connections, and modify neuronal functioning

dendrites

a neuron's branches that receive information from other neurons and transmit it toward the cell body

cell body

the part of the neuron that keeps it alive and determines whether it will fire

axon

a neuron's extending fiber that conducts impulses away from the cell body and transmits them to other neurons or to muscle or gland cells

myelin sheath

a fatty insulation that may surround the axon of a neuron

nerve

a bundle of nerve fibers (axons and sometimes dendrites) in the peripheral nervous system

stem cells

immature cells that renew themselves and have the potential to develop into mature cells; given encouraging environments, stem cells from early embryos can develop into any cell type

synapse

the site where transmission of a nerve impulse from one nerve cell to another occurs; it includes the axon terminal, the synaptic cleft, and receptor sites in the membrane of the receiving cell

plasticity

the brain's ability to change and adapt in response to experience, for example, by reorganizing or growing new neural connections

action potential

a brief change in electrical voltage that occurs when a neuron is stimulated; it serves to produce an electrical impulse

neurotransmitter

a chemical substance that is released by a transmitting neuron at the synapse and that alters the activity of a receiving neuron

endorphins

chemical substances in the nervous system that are similar in structure and action to opiates; they are involved in pain reduction, pleasure, and memory and are known technically as endogenous opioid peptides

hormones

chemical substances, secreted by organs called glands, that affect the functioning of other organs

endoctrine glands

internal organs that produce hormones and release them into the bloodstream

melatonin

a hormone, secreted by the pineal gland, that is involved in the regulation of daily biological rhythms

oxytocin

a hormone, secreted by the pituitary gland, that stimulates uterine contractions during childbirth, facilitates the ejection of milk during nursing, and seems to promote, in both sexes. attachment and trust in relationships

adrenal hormones

hormones that are produced by the adrenal glands and that are involved in emotion and stress

sex hormones

hormones that regulate the development and functioning of reproductive organs and that stimulate the development of male and female sexual characteristics; they include androgens, estrogens, and progesterone

electrocephalogram (EEG)

a recording of neural activity detected by electrodes

transcranial magnetic stimulation (TMS)

a method of stimulating brain cells, using a powerful magnet field produced by a wire coil placed on a person's head; it can be used by researchers to temporarily inactivate neural circuits and is also being used therapeutically

PET scan (positron emission tomography)

a method for analyzing biochemical activity in the brain, for example by using injections of a glucose-like substance containing a radioactive element

MRI (magnetic resonance imaging)

a method for studying body and brain tissue, using magnetic fields and special radio receivers

localization of function

specialization of particular brain areas for particular functions

brain stem

the part of the brain at the top of the spinal cord, consisting of the medulla and the pons

pons

a structure in the brain stem involved in, among other things, sleeping, waking, and dreaming

medulla

a structure in the brain stem responsible for certain automatic functions, such as breathing and heart rate

reticular activating system (RAS)

a dense network of neurons in the core of the brain stem; it arouses the cortex and screens incoming information

cerebrum

a brain structure that regulates movement and balance and that is involved in some cognitive tasks

thamalus

a brain structure that relays sensory messages to the cerebral cortex

hypothalamus

a brain structure involved in emotions and drives vital to survival; it regulates the autonomic nervous system

pituary gland

a small endocrine gland at the base of the brain that releases many hormones and regulates other endocrine glands

limbic system

a group of brain areas involved in emotional reactions and motivated behaviour

amygdala

a brain structure involved in the arousal and regulation of emotion and the initial emotional response to sensory information

hippocampus

a brain structure involved in the storage of new information in memory

cerebrum

the largest brain structure, consisting of the upper part of the brain; divided into two hemispheres, it is in charge of most sensory, motor, and cognitive processes

cerebral hemispheres

the two halves of the cerebrum

corpus callosum

the bundle of nerve fibers connecting the two cerebral hemispheres

laterization

specialization of the two cerebral hemispheres for particular operations

cerebral cortex

a collection of several thin layers of cells covering the cerebrum; it is largely responsible for higher mental functions

occiptal lobes

lobes at the lower back part of the brain's cerebral cortex; they contain areas that receive visual information

parietal lobes

lobes at the top of the brain's cerebral cortex; they contain areas that receive information on pressure, pain, touch, and temperature

temporal lobes

lobes at the sides of the brain's cerebral cortex; they contain areas involved in hearing, memory, perception, emotion, and (in the left lobe, typically) language comprehension

frontal lobes

lobes at the front of the brain's cerebral cortex; they contain areas involved in short-term memory, higher-order thinking, initiative, social judgement, and (in the left lobe, typically) speech production