Chapter 4 Flashcards
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 bone (the spinal column)
Spinal Cord
Th portion of the nervous system consisting of the brain and spinal cord
Central Nervous System (CNS)
behaviors produced by the spinal cord without any help from the brain
Spinal Reflexes
Carry messages from special receptors in the skin, muscles, and other internal and external sense organs to the spinal cord, which sends them along to the brain
Sensory Nerves
All portions of the nervous system outside the brain and spinal cord; it includes sensory and motor nerves
Peripheral Nervous System (PNS)
Carry orders from the central nervous system to muscles, glands, and internal organs
Motor Nerves
Chemical messengers
Hormones
The subdivision of the peripheral nervous system that connects to sensory receptors and to skeletal muscles
Somatic Nervous System
The subdivision of the peripheral nervous system that regulates the internal organs and glands
Autonomic Nervous System
The subdivision of the autonomic nervous system that mobilizes bodily resources and increases the output of energy during emotion and stress
Sympathetic Nervous System
The subdivision of the autonomic nervous system that operates during relaxed states and that conserves energy
Parasympathetic Nervous System
A cell that conducts electrochemical signals; the basic unit of the nervous system
Neuron
Cells that support, nurture, and insulate neurons, remove debris when neurons die, enhance the formation and maintenance of neural connections, and modify neuronal functioning
Glia
A neuron’s branches that receive information from other neurons and transmit it toward the cell body
Dendrites
The part of the neuron that keeps it alive and determines whether or not it will fire
Cell Body
Branches at the end of axons
Axon Terminals
A neuron’s extending fiber that conducts impulses away from the cell body and transmits them to other neurons
Axon
A fatty insulation that may surround the axon of a neuron
Myelin Sheath
Constrictions in the myelin sheath
Nodes
A bundle of nerves fibers (axons and sometimes dendrites) in the peripheral nervous system
Nerve
The production of new neurons from immature stem cells
Neurogenesis
Immature cells that renew themselves and have the potential to develop into mature cells
Stem Cells
minuscule space in between neurons where the axon terminal of one neuron nearly touches a dendrite or the cell body of another
Synaptic Cleft
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
Synapse
A brief change in electrical voltage that occurs between the inside and the outside of an axon when a neuron is stimulated; it serves to produce an electrical impulse
Action Potential
Special molecules in the membrane of the receiving neuron’s dendrites (or sometimes cell body)
Receptor Sites
Tiny sacs in the tip of the axon terminal
Synaptic Vesicles
A chemical substance that is released by a transmitting neuron at the synapse and that alters the activity of a receiving neuron
Neurotransmitter
When a charge reaches a critical level and the neuron will fire
Excitatory Effect
When a neurotransmitter causes an increase in the negative charge making the neuron likely to fire
Inhibitory Response
Affects neurons involved in sleep, appetite, sensory perception, temperature regulation, pain suppression, and mood
Serotonin
Affects neurons involved in voluntary movement, attention, learning, memory, emotion, pleasure and reward, and possibly responses to novelty
Dopamine
Affects neurons involved in muscle action, arousal, vigilance, memory, and emotion
Acetylcholine
Affects neurons involved in increases heart rate and the slowing of intestinal activity during stress, and neurons involved in learning, memory, dreaming, waking from sleep, and emotion
Norepinephrine
Major inhibitory neurotransmitter in the brain
GABA (gamma-aminobutyric acid)
The major excitatory neurotransmitter in the brain; it is released by about 90 percent of the brain’s neurons
Glutamate
Chemical substances secreted by organs called glands, that affect the functioning of other organs
Hormones
Internal organs that produce hormones and release them into the bloodstream
Endocrine Glands
A hormone, secreted by the pineal gland, that is involved in the regulation of daily biological rhythms
Melatonin
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
Oxytocin
Hormones that are produced by the adrenal glands and that are involved in emotion and stress
Adrenal 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
Sex Hormones
Endocrine gland in the brain that produces melatonin
Pineal Gland
Promotes attachment and trust in both sexes in conjunction with oxytocin
Vasopressin
Increases blood-sugar levels and boosts energy; produced by the outer part of each adrenal gland
Cortisol
Adrenaline
Epinephrine
A protein that acts like a garbage collector, picking up serotonin from the synaptic cleft after it has been released and transporting it back to the sending neuron for recycling
Serotonin Transporter
Neurochemicals that modulate that functioning of neurons and neurotransmitters
Neuromodulators
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
Endorphins
The removal of disabling of a brain structure to gain better understanding of its function; this method is used only in animals
Lesion Method
A method of stimulating brain cells, using a powerful magnetic field produced by a wire coil placed on a person’s head; it can be used by researchers to temporarily inactive neural circuits
Transcranial Magnetic Stimulation (TMS)
A technique that applies a very small electric current to stimulate or suppress activity in parts of the cortex; it enables researchers to identify the functions of a particular area
Transcranial Direct Current Stimulation (tDCS)
A recoding of neural activity detected by electrodes
Electroencephalogram (EEG)
A technique that isolates the neural activity associated with a specific stimulus
Event-Related Potentials (ERP)
A method for analyzing biochemical activity in the brain, for example by using injections of a glucose-like substance containing a radioactive element
PET scan (positron-emission tomography)
A method for studying body and brain tissue, using agnetic fields and special radio receivers
MRI (magnetic resonance imaging)
A type of magnetic resonance imaging used to study brain activity associated with specific thoughts and behaviors
fMRI (functional magnetic resonance imaging)
Specialization of particular brain areas for particular functions
Localization of Function
The part of the brain at the top of the spinal cord, consisting of the medulla and the pons
Brain Stem
A structure in the brain stem involved in, among other things, sleeping, waking, and dreaming
Pons
A structure in the brain stem responsible for certain automatic functions, such as breathing and heart rate
Medulla
A dense network of neurons found in the core of the brain stem; it arouses the cortex and screens incoming information
Reticular Activating System (RAS)
