Biopsychology: Final Exam
Terms
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- Central Nervous System
- The brain and spinal cord
- Peripheral nervous system
- The part of the nervous system outside the brain and spinal cord, including the nerves attached to the brain and spinal cord.
- Soma
- The cell body of a neuron, which contains the nucleus
- dendrite
- A branched, treelike structure attached to the soma of a neuron; recieves information from the termnal buttons of other neurons
- synapse
- A junction between the terminal button of an axon and the membrand of another neuron.
- axon
- The long, thin, cylindrical structure that conveys info. from the soma of a neuron to its terminal buttons.
- multipolar neuron
- A neuron with one axon and many dendrites attached to its soma
- Bipolar neuron
- A neuron with one axon and one dendrite attached to its soma
- Unipolar neuron
- A neuron with one axon attached to its soma: the axon divides, with one branch recieving sensory information and the other sending the info to the CNS.
- Terminal buttons
- The bud at the end of a branch of an axon; forms synapses with another neuron; sends info. to that neuron.
- neurotransmitter
- A chemical that is released by a terminal button; has an excitatory or inhibitory effect on another neuron.
- membrane
- a structure consisting principilly of lipid molecules that defines the outer boundaries of a cell and also constitutes many of the cell organelles.
- cytoplasm
- The viscous, semi-liquid substance contained in the interior of a cell.
- mitochondria
- An organelle that is responsible for extracting energy from nutrients. Has own DNA sequence and reproduces independently.
- Adenosine Triphosphate (ATP)
- A molecule of prime importance to cellular energy metabolism; its breakdown liberates energy
- nucleus
- A structure in the central region of a cell, containing the chromosomes.
- gene
- the functional unit of the chromosome, which directs synthesis of one or more proteins.
- cytoskeleton
- Formed of microtubules and otehr protein fibers, linked to each other and forming a cohesive mass that gives a cell shape.
- enzyme
- A molecule that controls a chemical reaction, combining two substances or breaking a substance into two parts. The marriage brokers and divorce judges of the cell.
- Axoplasmic transport
- An active process by which substances are propelled along microtubules that run the length of the axon.
- microtubule
- A long strand of bundles of protein filaments arranged around a hollow core; part of the cytoskeleton and involved in transporting substances from place to place within the cell.
- astrocyte
- A glial cell that provides support for neurons of the CNS, provides nutrients and other substances, and and regulates the chemical composition of extracellular fluid.
- oligodendrocyte
- A type of glial cell in the CNS that forms myelin sheaths
- Myelin Sheath
- A sheath the surrounds axons and insulates tham, preventing messages from spreading between adjacent axons.
- node of Ranvier
- A naked portion of a myelinated axon, between adjacent oligodendroglia or Achwann cells.
- microglia
- The smallest of glial cells; act as phagocytes and protect the brain from invading microorganisms.
- Schwann cell
- A cell in teh peripheral nervous system that is wrapped around a myelinated axon, providing one segment of its myelin sheath.
- blood-brain barrier
- A semi-permeable barrier between the blood and the brain produced by the cells in the walls of the brain's capillaries.
- area postrema
- A region of the medulla where the blood-brain barrier is weak; poisons can be detected there and induce vomitting.
- membrane potential
- The electrical charge across a cell membrane; the difference in electrical potential inside and outside the cell.
- resting potential
- The membrane potential of a neuron when it is not being altered by excitatory or inhibitory postsynaptic potentials; approx. -70mV in the giant squid axon.
- depolarization
- Reduction (towards zero)of the membrane potential of a cell from its normal resting potential.
- hyperpolarization
- An increase in the membrane potential of a cell, relative to the normal resting potential.
- action potential
- The brief electrical impulse that provides the basis for conduction of information along an axon.
- threshold of excitation
- The calue of the membrane potential that must be reached to produce an action potential.
- diffusion
- Movement of molecules from refions of high concentration to regions of low concentration.
- electrolyte
- An aqeous solution of a material that ionizes--namely, a soluble acid, base or salt
- ion
- A charged molecule. Cations are positively charged, and anions are negatively charged.
- electrostatic pressure
- The attractive force between atomic particles charged with opposite signs or the repulsive force between atomic particles charged with the same sign.
- intracellular fluid
- fluid inside the cell; usually contains potassium K+ and organic anions A-.
- extracellular fluid
- Body fluids outside of the cells. Think sea water...mostly sodium cations NA+ and chloride anions Cl-
- sodium-potassium transporter
- A protein found in the membrand of all cells that extrudes sodium ions from and transports potassium ions into the cell.
- ion channel
- A specialized protein molecule that permits specific ions to enter or leave cells.
- voltage dependent ion channel
- An ion channel that opens or closes according to the value of the membrane potential.
- All-or-none law
- The principle that once an action potential is triggered in an axon, it is propagated, without decrement, to the end of the fiber.
- rate law
- The principle that variations in the intensity of a stimulus or other information being transmitted in an axon are represented by variations in the rate at which that axon fires.
- saltatory conduction
- Conduction of action potentials by myelinated axons. The action potential appears to jump from one node of Ranvier to the next.
- postsynaptic potential
- Alterations in the membrane potential of a postsynaptic neuron, produced by liberations of neurotransmitter at the synapse.
- binding site
- The location on a receptor protein to which a ligand binds.
- ligand
- A chemical that binds with the binding site of a receptor.
- dendritic spine
- A small bud on the surface of a dendrite, with which a terminal button of another neuron forms a synapse.
- Presynaptic membrane
- The cell membrane opposite the terminal button in a synapse; the membrane of the cell that receives the message.
- synaptic cleft
- The space between the presynaptic membrane and the postsynaptic membrane.
- synaptic vesicle
- A small, hollow, beadlike structure found in terminal buttons; contains molecules of a neurotransmitter.
- release zone
- A region of the interior of the presynaptic membrane of a synapse to which synaptic vessicles attach and release their neurotransmitter into the synaptic cleft.
- postsynaptic receptor
- A receptor molecule in the postsynaptic membrane of a synapse that contains a binding site for a neurotransmitter.
- neurotransmitter-dependent ion channel
- An ion channel that opens when a molecule of a neurotransmitter binds with a post-synaptic receptor.
- ionotropic receptor
- A receptor that contains a binding site for a neurotransmitter and an ion channel that opens when a milecule of the neurotransmitter attaches to the bindng site.
- metabotropic receptor
- A receptor that contains a binding site for a neurotransmitter; activates an enzyme that begins a series of events that opens an ion channel elsewhere in the membrane of the cell when a molecule of the neurotransmitter attaches to the binding site.
- G protein
- A protein coupled to a metabotropic receptor; conveys messages to other molecules when a ligand binds with and activates the receptor.
- second messenger
- A chemical produced when a G-protein activates an enzyme; carries a signal that results in the opening of the ion channel or causes other events to occur in the cell.
- excitatory postsynaptic potential (EPSP)
- An excitatory depolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button.
- inhibitory postsynaptic potential (IPSP)
- inhibitory hyperpolarization of the postsynaptic membrane of a synapse caused by the liberation of a neurotransmitter by the terminal button.
- reuptake
- The reentry of a neurotransmitter just liberated by a terminal button back through its membrane, thus terminating the postsynaptic potential.
- enzymatic deactivation
- The destruction of a neurotransmitter by an enzyme after its release--for example, the destruction of ACh by AChE
- acetylcholine (ACh)
- A neurotransmitter found in the brain, spinal cord and parts of the peripheral nervous system; responsible for muscular contraction.
- Acetylcholinesterase (AChE)
- The enzyme that destroys ACh soon after it is liberated by the terminal buttons thus terminating the postsynaptic potential
- neural integration
- The process by which inhibitory and excitatory postsynaptic potentials summate and control the rate of firing of a neuron.
- Autoreceptor
- A receptor molecule located on a neuron that responds to the neurotransmitter released by that neuron.
- presynaptic inhibition
- The action of a presynaptic terminal button in a axoaxonic synapse; reduces the amount of neurotransmitter released by the postsynaptic terminal button.
- presynaptic facilitation
- The action of a presynaptic terminal button in an axoaxonic synapse; increases the amount of neurotransmitter released by the postsynaptic terminal button.
- neuromodulator
- A naturally secreted substance that acts like a neurotransmitter except that it is not restricted to the synaptic cleft but diffuses through the extracellular fluid.
- caudal
- "Toward the tail"; with respect to the CNS, in a direction along the neuraxis away from the front of the face.
- dorsal
- "toward the back"; with respect to the CNS, in a direction perpendicular to the neuraxis toward the top of the head or the back.
- ventral
- "toward the belly"; in a direction perpendicular to the neuraxis toward the bottom of the skull or the front surface of the body.
- lateral
- Toward the side of the body
- medial
- toward the middle of the body
- ipsilateral
- Located on the same side of the body
- contralateral
- Located on the opposite side of the body.
- cross section
- With respect to the central nervous system, a slice taken at right to the neuraxis.
- frontal section
- A slice through the brain parallel to the forehead.
- horizontal section
- a slice through the brain parallel to the ground.
- meninges
- The three layers of tissue that encase the CNS: the dura mater, arachnoid membrane, and pia mater.
- dura mater
- The outermost of the meninges: tough and flexible
- arachnoid membrane
- The middle layer of the meninges, located between the outer dura mater and inner pia mater.
- pia mater
- The layer of the meninges that clings to the surface of the brain, thin and delicate.
- subarachnoid space
- The fluid filled space that cushions the brain; located between the arachnoid membrane and the pia mater.
- Ventricle
- One of the hollow spaces within the brain, filled with CSF
- lateral ventricle
- One of the two ventricles located in the center of the telencephalon.
- third ventricle
- The ventricle located in the center of the diencephalon.
- cerebral aqueduct
- A narrow tube interconnecting the third and fourth ventricles of the brain, located in the center of the mesencephalon.
- choroid plexus
- The highly vascular tissue that protrudes into the ventricles and produces CSF.
- cerebral cortex
- The outermost layer of gray matter of the cerebral hemispheres.
- forebrain
- The most rostral of the three major divisions of the brain; includes the telencephalon and diencephalon.
- cerebral hemisphere
- One of the two major portions of the forebrain, covered by the cerebral cortex.
- subcortical region
- The region located within the brain, beneath the cortical surface.
- sulcus
- A groove in the surface of the cerebral hemisphere, smaller than a fissure.
- fissure
- A major groove in the surface of the brain, larger than a sulcus.
- gyrus
- A convolution of the cortex of the cerebral hemispheres, separated by sulci or fissures.
- calcarine fissure
- A fissure located in the occipital loce on the medial surface of the brain; most of the primary visual cortex is located along its upper and lower banks.
- primary auditory cortex
- The region of the superior temporal love whose primary input is from the auditory system.
- lateral fissure
- The fissure that separates the temporal lobe from the overlying frontal and parietal lobes.
- primary somatosensory cortex
- The region of teh anterior parietal lobe whose primary input is from the somatosensory system.
- central sulcus
- The sulcus that separates the frontal lobe from the parietal lobe.
- primary motor cortex
- The region of the posterior frontal lobe that contains neurons that control movements of skeletal muscles.
- frontal lobe
- The anterior portion of the cerebral cortex, rostral to the parietal lobe and dorsal to the temporal lobe.
- parietal lobe
- The region of teh cerebral cortex caudal to the frontal lobe and dorsal to the temporal lobe.
- Temporal lobe
- The region of the cerebral cortex rostral to the occipital lobe and ventral to the parietal and frontal lobe.
- occipital lobe
- The region of the cerebral cortex caudal to the parietal and temporal lobes.
- sensory association cortex
- Those regions of the cerebral cortex that receive info. from the regions of primary sensory cortex.
- motor association cortex
- The region of the frontal lobe rostral to the primary motor cortex, also known as the premotor cortex.
- prefrontal cortex
- The region of the frontal lobe rostral to the motor assoc. cortex.
- corpus callosum
- A large bundle of axons that interconnects corresponding regions of the association cortex on each side of the brain.
- neocortex
- The phylogenetically newest cortex, including the primary sensory cortex, primary motor cortex and association cortex.
- limbic cortex
- Phylogenetically old cortex, located at the medial edge ("limbus") of the cerebral hemispheres; part of the limbic system
- cingulate gyrus
- A strip of limbic cortex lying along the lateral walls of the groove separating the cerebral hemispheres, just above the corpus callosum.
- limbic system
- A group of brain regions including the anterior thalamic nuclei, amygdala, hippocampus, limbic cortex, and parts of the hypothalamus, as well as their interconnecting bundles.
- hippocampus
- A forebrain structure of the temporal lobe, constituting an important part of the limbic system; includes the hippocampus proper, dentate gyrus, and subiculum.
- amygdala
- A structure in the interior of the rostral temporal lobe, containing a set of nuclei; part of the limbic system.
- fornix
- A fiber bundle that connects the hippocampus with other parts of the brain, including the mammillary bodies of the hypothalamus; part of limbic system.
- basal ganglia
- A group of subcortical nuclei in the telencephalon, the caudate nucleus, the globus pallidus, and the putamen; important parts of the motor system.
- diencephalon
- A region of the forebrain surrounding the third ventricle, includes the thalamus and the hypothalamus.
- thalamus
- The largest portion of the diencephalon, located above the hypothalamus, contains nuclei that project info to specific regions of the cerebral cortex and receive info from it.
- lateral geniculate nucleus
- A group of cell bodies within the lateral geniculate body of the thalamus that receives fibers from the retina and projects fibers to the primary visual cortex.
- medial geniculate nucleus
- A group of cell bodies within the medial geniculate body of the thalamus; receives fibers from the auditory system and projects fibers to the primary auditory cortex.
- ventrolateral nucleus
- A nucleus of the thalamus that receives inputs from the cerebellum and sends axons to the primary motor cortex.
- hypothalamus
- The group of nuclei of the diencephalon situated beneath the thalamus; involved in reg. of autonomic nervous system, control of the anterior and posterior pituitary glands and integration of species typical behaviors.
- optic chiasm
- An X shaped connection between the optic nerves, located below the base of the brain, just anterior to the pituiary gland.
- anterior pituiatary gland
- The anterior part of the pituiatary gland, an endocrine gland whose secretions are controlled by the hypothalamic hormones.
- posterior pituitary gland
- The posterior part of the pituitary gland; an endocrine gland that contains hormone-secreting terminal buttons of axons whose cell bodies lie within the hypothalamus.
- midbrain (mesencephalon)
- The mesencephalon; the central of the three major divisions of the brain. surrounds the cerebral aqueduct: includes the tectum and tegmentum.
- Tectum
- The dorsal part of the midbrain' includes superior and inferior colliculi.
- brain stem
- The stem of the brain, from the medulla to the diencephalon, excluding the cerebellum
- tegmentum
- The ventrla part of the midbrain; includes periaqueductal gray matter, reticular formation, red nucleus and substantia nigra
- reticular formation
- A large network of neural tissue located in the central region of the brain stem, from the medulla to the diencephalon.
- periaqueductal gray matter
- The region of the midbrain surrounding the cerebral aqueduct: contains neural circuits involved in species-typical behaviors.
- red nucleus
- A large nucleus of the midbrain that receives inputs from the cerebellum and motor cortex and sends axons to motor neurons in the spinal cord.
- substantia nigra
- A darkly stained region of the tegmentum that contains neurons that communicate with the caudate nucleus and putamen in the basal ganglia.
- hindbrain
- The most caudal of the three major divisions of the brain; includes the metencephalon and myelencephalon
- cerebellum
- A major part of the brain located dorsal to the pons, containinf the two cerebellar hemispheres, covered with the cerebellar cortex; an important component of the motor system.
- cerebellar cortex
- The cortex that covers the surface of the cerebellum.
- pons
- The region os the metencephalon rostral to the medulla, caudal to the midbrain and central to the cerebellum
- medulla oblongata
- The most caudal portion of the brain; located in the myelencephalon, immediately rostral to the spinal cord.
- spinal root
- A bundle of axons surrounded by connective tissue that occurs in pairs, which fuse and form a spinal nerve.
- dorsal root
- The spinal root that contains incoming (afferent) sensory fibers
- ventral root
- The spinal root that contains outgoing (efferent) motor fibers.
- cranial nerve
- A peripheral nerve attached directly to the brain. 12
- vagus nerve
- The largest of the cranial nerves, conveying efferent fibers of the parasympathetic division of the autonomic nervous system to organs of the thoracic and abdominal cavities.
- somatic nervous system
- The part of the peripheral nercous sustem that controls the movement of skeletal muscles or transmits somatosensory info to the CNS
- Autonomic nervous system
- The portion of the peripheral nervous system that controls the body's vegetative functions.
- sympathetic division
- nodules that contain synapses between preganglionic and postganglionic neurons of the sympathetic nervous system.
- parasympathetic division
- The portion of the ANS that controls functions that occur during a relaxed state.
- pharmokinetics
- The process by which drugs are absorbed, distributed within the body, metabolized and excreted.
- intraperitoneal (IP) injection
- injection of a substance into the peritoneal cavity-the space that surrounds the stomach, intestines, liver and other ab orgs.
- introcerebral administration
- administration of a substance directly into the brain
- intracerebrocentrucular (ICV) administration
- administation of a substance into one of the cerebral ventricles.
- dose response curve
- A graph of the magnitude of an effect of a drug as a function of the amount of drug administered.
- therapeutic index
- The ratio between the dose that produces the desired effect in 50 percent of the animals and the dose that produces toxic effects in 50 percent of the animals.
- affinity
- The readiness with which two molecules join together.
- antagonist
- A drug that opposes or inhibits the effects of a particular neurotransmitter on the post synaptic cell
- agonist
- A drug that facilitates the effects of a particular neurotransmitter on the postsynaptic cell.
- direct agonist
- A drug that binds with and activates a receptor.
- receptor blocker (direct antagonist)
- A drug that binds with a receptor but does not activate it; prevents the natural ligand from binding with the receptor.
- noncompetitive binding
- Binding of a drug to a site on a receptor; does not interfere with the binding site for the principal ligand.
- indirect antagonist
- A drug that attaches to a binding site on a receptor and interferes with the action of the receptor; does not interfere with the binding site for the principal ligand.
- indirect agonist
- A drug that attaches to a binding site on a receptor and facilitates the action of the receptor; does not interfere with the binding site for the principal ligand.
- acetyl-CoA
- A cofactor that aupplies acetate for the synthesis of acetylcholine
- choline acetyltranferase (ChAT)
- The enzyme that transfers the acetate ion from acetyl coenzyme A to choline, producing the neurotransmitter acetylcholine.
- botulinum toxin
- An acetylcholine antagonist; prevents release by terminal buttons
- black widow spider venom
- A poison produced by the black widow spider that triggers the release of acetylcholine
- neostigmine
- A drug that inhibits the activity of acetylcholintransferase...thus inhibiting synthesis of acetylcholine
- nicotinic receptor
- An ionotropic acetylcholine receptor that is stimulated b nicotine and blocked by curare.
- muscarinic receptor
- A metabotropic acetylcholine receptor that is stimulated by muscarine and blocked by atropine.
- monoamine
- A class of amines that includes indolamines such as serotonin and catecholamines such as dopamine, norephinephrine, and epinephrine
- catecholamine
- A class of amines that includes the neurotransmitters dopamine, norepinephrine, and epinephrine
- dopamine
- a neurotransmitter: implicated in movement, attention, learnine, and the reinforcing effects of drugs
- L Dopa
- The levorotatory form of DOPA; the precursor of the catecholamines; often used for treatment of Parkinson's b/c of its effects as a dopamine agonist
- nigrostriatal system
- A system of neurons originating in the ventral tegmental area and terminating in teh nucleus accumbens, amygdala, and hippocampus
- mesolimbic system
- A system of dopaminergic neurons originating in the ventral tegmental area and terminating in the nucleus accumbens, amygdala, and hippocampus
- mesocortical system
- A system of dopaminergic neurons originating in the ventral tegmental area and terminating in the prefrontal cortex.
- AMPT
- A drug that block the activity of tyrosine hydroxylase and thus interferes with the synthesis of the catecholamines
- reserpine
- A drug that interferes with the storage of monoamines in synaptic vesicles.
- methylphenidate
- a drug that inhibits the reuptake of dopamine
- monoamine oxidase (MAO)
- A class of enzymes that destroy the monoamines: dopamine, norepinephrine, and serotonin
- deprenyl
- A drug that block the activity of MAO-B; acts as a dopamine agonist
- chlorpromazine
- A dopamine receptor blocker; a commonly prescribed antischizophrenic drug.
- Clozapine
- A drug that reduces the symptoms of schizophrenia; apparently by blocking dopamine D4 receptors
- norepinephrine
- one of the catecholamines, a neurotransmitter found in the brain and in teh sympathetic division of the ANS. Implicated in vigilance and attentiveness to events in environment
- idazoxan
- A drug that blocks the presynaptic noradrenergic a2 receptors and hence acts as anagonist, stimulating synthesis and release of NE
- serotonin (5-HT)
- An indolamine neurotransmitter; implicated in regulation of mood, eating, sleeping, arousal, and regulation of pain
- PCPA
- A drug that inhibits the activity of tryptophan hydroxylase and thus interferes with the sythesis of serotonin
- fluoxetine
- A drug that inhibits the reuptake of 5-HT
- fenfluramine
- A drug that stimulates the release of serotonin
- glutamate
- An amino acid; the most important excitatory neurotransmitter in the brain
- NMDA receptor
- A specialized ionotropic glutamate receptor that controls a calcium channel that is normally blcoked by Mg2+ ions; has several other binding sites
- AMPA receptor
- An ionotropic glutamate receptor that controls a sodium channel; stimulated by AMPA
- kainate receptor
- An ionotropic glutamate receptor that controls a sodium channel stimulated by kainic acid.
- metabotropic glutamate receptor
- A category of metabotropic receptors that are sensitive to glutamate
- GABA
- An amino acid, the most important inhibitory neurotransmitter in the brain
- anxiolytic
- An anxiety reducing effect
- benzodiazepine
- A category of anxiolytic drugs; an indirect agonist for the GABA A receptor
- glycine
- an amino acid, an important inhibitory neurotransmitter in the lower brain stem and spinal cord.
- adenosine
- A nucleoside, a combo of ribose and adenine; serves as a neuromodulator in the brain
- positive symptom
- A symptom of schizophrenia evident by its presence: delusions, hallucinations, disordered thoughts, and often bizzare behaviors.
- negative symptoms
- A symptom of schizophrenia characterized by the absence of behaviors that are normally present; social withdrawal, lack of affect, and reduced motivation.
- seasonality effect
- The increased incidence of schizophrenia in people born during late winter ane early spring.
- hypofrontality
- Decreased activity of the prefrontal cortex; believed to be responsible for the negative synptoms of schizophrenia.
- tricyclic antidepressant
- A class of drugs, used to treat depression; inhibits the reuptake of norepinephrine and serotonin; named for the molecular structure
- specific serotonin reuptake inhibitor
- A drug that inhibits the reuptake of serotonin without affecting the reuptake of other neurotransmitters.
- electroconvulsive therapy (ECT)
- A brief electrical shock; applied to the head, that results in an electrical seizure, used therapeutically to alleviate severe depression
- carbamazepine
- A drug(trade name: Tegretol) that is used to treat seizures originating from a focus, generally in the medial temporal lobe
- monoamine hypothesis
- A hypothesis that depression is caused by a low level of activity of one or more monoaminergic synapses.
- 5-HIAA
- A breakdown product of the neurotransmitter serotonin (5-HT)
- tryptophan depletion procedure
- A procedure involving a low-tryptophan diet and a tryptophan free amini acid "cocktail" that lowers brain tryptophan and consequently decreases the synthesis of 5-HT
- anticipatory anxiety
- A fear of having a panic attack; may lead to the development of agorophobia (fear of open spaces)
- cingulotomy
- The surgical destruction of the cingulum bundle, which connects the prefrontal cortex with the limbic system; helps to reduce intense anxiety and the symptoms of OCD
- fight or flight response
- A species typical response preparatory to fighting or fleeing; thought to be responsible for some of the deleterious effects of stressful situations on health.
- glucocorticoid
- One of a group of hormones of the adrenal cortex that are important in protein and carbohydrate metabolism, secreted especially in times of stress.
- corticotropin-releasing hormone (CRH)
- A hypothalamic hormone that stimulates the anteriory pituitary gland to secrete ACTH (adrenocorticotropic hormone).
- adrenocorticotropic hormone (ACTH)
- A hormone released by the anterior pituitary gland in response to CRH; stimulates the adrenal cortex to produce glucocorticoids.
- coping response
- A response through which an organism can avoid, escape from, or minimize an aversive stimulus; reduces the stressful effects of an aversive stimulus.
- antigen
- A protein present on a microorganism that permits the immune system to recognize the microorganism as an invader.
- antibody
- A protein produced by a cell of the immune system that recognizes antigens present on invading microorganisms.
- negative reinforcement
- The removal or refuction of an aversive stimulus that is contigent on a particular response, whith an attendant increase in the frequency of that response.
- naltrexone
- A drug that blocks mu opiate receptors; antagonizes the reinforcing and sedative effects of opiates.