Biomaterial Database

Effect of unconditioned stimulus magnitude on the emergence of conditioned responding. 2006

Richard W Morris, and Mark E Bouton

Department of Psychology, University of Vermont, Burlington, VT 05401, USA.

Although unconditioned stimulus (US) magnitude influences conditioning, no experiment has addressed whether it influences a decision point at which the organism first responds (Gallistel & Gibbon, 2000). Two appetitive conditioning experiments with rats confirmed that the rate of food cup entries and proportion of head jerking were related to the number of pellets (US) provided after the conditioned stimulus. In addition, the onset of responding measured by the number of reinforcers to a criterion or by a quantitatively identified change point also reflected US magnitude. Two aversive conditioning experiments also found that the amount and onset of freezing were related to footshock intensity. All experiments identified a trial at which responding increased abruptly in individual subjects. However, the point where the increase occurred was earlier with larger USs.

UI	MeSH Term	Description	Entries
D009068	Movement	The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.	Movements
D011897	Random Allocation	A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.	Randomization,Allocation, Random
D012054	Reinforcement, Psychology	The strengthening of a conditioned response.	Negative Reinforcement,Positive Reinforcement,Psychological Reinforcement,Reinforcement (Psychology),Negative Reinforcements,Positive Reinforcements,Psychological Reinforcements,Psychology Reinforcement,Psychology Reinforcements,Reinforcement, Negative,Reinforcement, Positive,Reinforcement, Psychological,Reinforcements (Psychology),Reinforcements, Negative,Reinforcements, Positive,Reinforcements, Psychological,Reinforcements, Psychology
D003214	Conditioning, Classical	Learning that takes place when a conditioned stimulus is paired with an unconditioned stimulus.	Reflex, Conditioned,Classical Conditioning,Classical Conditionings,Conditioned Reflex,Conditionings, Classical
D005260	Female		Females
D006257	Head	The upper part of the human body, or the front or upper part of the body of an animal, typically separated from the rest of the body by a neck, and containing the brain, mouth, and sense organs.	Heads
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001070	Appetitive Behavior	Animal searching behavior. The variable introductory phase of an instinctive behavior pattern or sequence, e.g., looking for food, or sequential courtship patterns prior to mating.	Searching Behavior,Appetitive Behaviors,Behavior, Appetitive,Behavior, Searching,Behaviors, Appetitive,Behaviors, Searching,Searching Behaviors
D001522	Behavior, Animal	The observable response an animal makes to any situation.	Autotomy Animal,Animal Behavior,Animal Behaviors
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats