Chapter 7
Learning: Behavior changed by experience

Classical/Pavlovian Conditioning: UCS is controlled by CS

Habituation: Simplest form of learning; learning not to respond to an unimportant even that occurs repeatedly

George Humphrey, studied land snails

Rankin: worm (nematoda) = habituation to tap-elicited withdrawal without affecting heat stimulus

Orienting response: Any response by which an organism directs appropriate sensory organs toward the source of a novel stimulus

Types (To distinguish, patterns of experience)

Short-term habituation *massed, quick

Long-term habituation *small groups, spaced (more complex animals

Ivan Pavlov

  • dogs began to salivate before being fed (saw lab assistant going into the room)
  • bell + food in mouth = saliva
  • bell = saliva

Functions

Components of
Classical Conditioning

UCR Unconditional Response: A response that is naturally elicited by UCS

CS Conditional Stimulus: a stimulus associated with UCS = CR

UCS Unconditional Stimulus: a stimulus that naturally elicits a reflexive response

CR Conditional Response: the response elicited by the CS

Pavlov's Phenomena

Recognizing stimuli that predicts occurrences allows learner to respond quickly *Hollis studied Siamese fighting fish

Unimportant stimuli can become important stimuli: desirable interchangeable with undesirable
Ward-Robinson (pigeons)
Krank (rats)

Acquisition: the time during which a CR first appears and increases in frequency

Spontaneous Recovery: After an interval of time, the reappearance of a response that had previously been extinguished

(Stimulus) Generalization: CRs elicited by stimuli that resemble the CS used in training

Discrimination: The appearance of a CR when one stimulus is presented (the CS+) but not another (the CS-)

Extinction: the elimination of a response that occurs when the CS is repeatedly presented without being followed by the UCS

Conditional Emotional Responses:
Todrank, Byrnes, Wrzesniewski and Rozin: pictures & odor ranking attractiveness. Rank depends of odor preference. CC role in development of personal likes/dislikes or emotional reactions
Phobia: Unreasonable fear of specific objects/situations learned through CC

Dalhousie University:
CC = CS must be predictor of UCS

Learned CC

Neutral stimulus = CS when:
CS regularly occurs prior to the presentation of the UCS
The CS does not regularly occur when the UCS is absent

Blocking:The prevention of or attenuation in learning that occurs to a neural CS when it is conditioned in the presence of a previously conditioned stimulus

The what and where of future events

When:

  • Inhibitory conditional response: A response tendency conditioned to a signal that predicts the absence of the UCS; generally not observed directly but assessed through other tests
  • Excitatory conditional response: A response tendency conditioned to a signal that the UCS is about to occur. This is the type of CR exemplified by Pavlov's salivation response
  • Cole and Miller (1999) trained rats, speculated that a form of temporal integration would occur, and that the rats would demonstrate an excitatory CR
  • Results: Even though the CS(f) had never been presented prior to a UCS, the rats behaved as though it signaled an upcoming UCS

What:

  • Resclora suggests behavior is determined by memory of the event
  • Hollis, Langworthy-Lam, Blouin and Romano (2004) used blue gouramis to demonstrate this idea
  • Results: it is not just the UCR that determines the CR, but rather the memory of what the CS predicts
  • Hilliard and Domjan (1995) examined sexual behaviors in male Japanese quail
  • Results: What was learned involved a memory of the UCS, a memory that could be altered by subsequent experience such as satiation

Operant Conditioning: A form of learning in which behavior is affected by its consequences. Favorable consequences strengthen the behavior and unfavorable consequences weaken the behavior.

The Law of Effect:
Thorndike's idea that the consequences of a behavior determine whether it is likely to be repeated

Natural selection determines which members of a species will survive and reproduce, while the law of effect determines which responses will survive and become part of the organism's behavioral repertoire

Skinner and Operant Behavior

Edward L. Thorndike

  • placed hungry cat inside "puzzle box"
  • successive trials of activating latch resulted in learning correct response because of the favorable outcome: food
  • Stimulated experimental studies aimed at understanding behavior-environment interactions; today, known as behavior analysis

Burrhaus Frederic Skinner

  • Studied law of effect and advocated the application of behavioral analysis and its methods to solving human problems
  • Devised objective methods for studying behavior by inventing an apparatus
  • Operant chamber: An apparatus by which an animal's behavior can be easily observed, manipulated and automatically recorded
  • A mechanical device connected to an operant chamber for the purpose of recording operant responses as they occur in time

Behavior analysts manipulate environmental events to determine their effects on response rate. Events that increase this rate strengthen responding; events that decrease the rate weaken responding

Skinner advances Thorndike's research methods because participants can:
(1) emit responses more freely over a greater time period
(2) be studied for longer periods of time without interference produced by the researcher handling or otherwise interacting with them between trials

The Three-Term
Contingency

Discriminative stimulus: the stimulus that sets the occasion for responding because, in the past, a behavior has produced certain consequences in the presence of that stimulus

Skinner distinguished:

  • The preceding event = the discriminative stimulus
  • The response we make = operant behavior
  • The following event - is the consequence of the operant behavior
    The consequences are produced by the behavior. In the presence of a discriminative stimuli, a consequence will only occur if an operant behavior occurs. Without this, the operant behavior will have no effect.

Conditions of Complex Behaviors

Reinforcement, Punishment, and Extinction

Punishment: A decrease in the frequency of a response that is regularly and reliably followed by an aversive stimulus

  • punisher: If an aversive stimulus follows a response and decreases the frequency of that response
    Negative side effects
  • Unrestrained use of physical force may cause serious bodily injury
  • Punishment often includes fear, hostility, and other undesirable emotions in people receiving punishment. It may result in retaliation against the punisher
    -Through punishment, organisms learn only which response not to make. Punishment does not teach the organism desirable responses

Reinforcement

Extinction: A decrease in the frequency of a response that is regularly and reliably followed by the termination of an appetitive stimulus

  • Behavior that is no longer reinforced decreases in frequency - it is said to extinguish

Response cost: A decrease in the frequency of a response that is regularly and reliably followed by the termination of an appetitive stimulus

  • Response cost is a form of punishment
  • time out from positive reinforcement: the procedure that produces response cost, when it is used to remove a person physically from an activity that is reinforcing to that person

Positive: and increase in the frequency of a response that is regularly and reliably followed by an appetitive stimulus

  • appetitive stimulus: any stimulus than an organism seeks out
  • positive reinforcer: when an appetitive stimulus follows a response and increases the frequency of that response

Negative: an increase in the frequency of a response that is regularly and reliably followed by the termination of an aversive stimulus

  • aversive stimulus: unpleasant or painful stimulus
  • negative reinforcer: when an aversive stimulus is terminated as soon as a response occurs and thus increases the frequency of that response

Other Operant Procedures and Phenomena

Resistance to Extinction and Intermittent Reinforcement

  • A response that has been reinforced intermittently is more resistant to extinction
  • An organism whose behavior has been reinforced intermittently has had a lot of experience making non-reinforced responses

Intermittent Reinforcement: The occasional reinforcement of a particular behavior; produces responding that is more resistant to extinction

  • Probability-based patterns require a variable number of responses for each reinforcer
  • Behavior analysts refer to this pattern of intermittent reinforcement as a ratio schedule of reinforcement

Generalization and Discrimination

Shaping: The occasional reinforcement of a particular behavior; produces responding that is more resistant to extinction

  • the target behavior: the behavior displayed by a person having the appropriate skill

Conditioned Reinforcement and Punishment

  • Fixed-interval schedule: A schedule of reinforcement in which the first response that is made after a fixed interval of time since the previous reinforcement (or the start of the session) is reinforced

  • Variable-ratio schedule: A schedule of reinforcement similar to a fixed-ratio schedule but characterized by a variable response requirement ha
  • Variable-interval schedule: A schedule of reinforcement similar to a fixed-interval schedule but characterized by a variable time requirement having a particular mean
  • Fixed-ratio schedule: A schedule of reinforcement in which reinforcement occurs only after a fixed number of responses have been made since the previous

Discrimination: responding only when a specific discriminative stimulus is present but not when similar stimuli are present

Generalization: the occurrence of responding when a stimulus similar (but not identical) to the discriminative stimulus is present

  • Herrnstein and Loveland (1964) trained pigeons to respond to the concept of a human being
  • Jitsumori and Yoshihara (1997) found that pigeons were generally using individual elements to form their categories
  • Njegovan and Weisman (1997) trained chickadees to discriminate different "songs" consisting a pair of notes

Primary punisher: A biologically significant aversive stimulus, such as pain

Primary reinforcers: A biologically significant appetitive stimulus, such as food or water

Conditioned (or secondary) reinforcer (or punisher): A stimulus that acquires its reinforcing properties through association with a primary reinforcer. Sometimes referred to as a secondary reinforcer.

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