Chapter 5: How Do We Learn?

Chapter 5: How Do We Learn?

Defining Learning A relatively permanent change in behavior or the potential for behavior that results from experience Results from many life experiences, not just structured ones May or may not be permanent change May or may not show up in behavior

Habituation Habituation when a stimulus is repeated over and over again the response to the stimulus decreases Universality Allows us to attend to potentially threatening stimuli or to tune out nonthreatening stimuli May protect brain from overstimulation

Classical Conditioning: Learning Through the Association of Stimuli Research on digestive processes: Pavlov noticed that his dogs learned to associate a cue (bell) with food Dogs became conditioned to respond to the cue (stimuli) the same way as food by salivating

The Elements of Classical Conditioning Unconditioned stimulus (US) naturally evokes unconditioned response (UR) Food (US) salivate (UR) Pair neutral (bell) and unconditioned stimuli (food) NS becomes a conditioned stimulus (CS) that produces a conditioned response (CR) Bell (NS) --- Salivate (CR)

Factors Affecting Classical Conditioning Relationship in time: contiguity NS/CS (bell) should precede the US (food) Consistency and reliability: contingency NC/CS (bell) should reliably predict the onset of the US (food)

Real-World Classical Conditioning Emotional responses Physiological responses

Classical Conditioning of Emotional Responses John Watson experiments with Little Albert Stimulus generalization similar stimuli to CS may elicit CR (from rats to furry things) Stimulus discrimination CR occurs in response to only specific stimuli

Classical Conditioning of Physiological Responses: Taste Aversion Taste aversions are often classically conditioned Acquired easily Single pairing is sufficient for learning Interval between pairings can be long Real life applications Survival value Diet Aversion therapy for alcoholism and chemotherapy

Extinction of Classically Conditioned Responses Extinction presenting CS (bell) without presenting the US (food) Pavlov s extinction trials Spontaneous recovery temporary increase in CR during or after extinction

Operant Conditioning Learning from the consequences of behavior E.L. Thorndike Worked with cat in puzzle box Cats learned to associate behavior (pull switch) with behavior s consequence (getting out of box)

E.L. Thorndike s Law of Effect Behaviors that lead to positive (satisfying) consequences will be strengthened and more likely Behaviors that lead to negative, (discomforting) consequences will be weakened and less likely to be emitted

Positive and Negative Reinforcement Positive reinforcement Behavior leads to something pleasant Negative reinforcement Behavior is rewarded by the removal of something unpleasant Negative reinforcement is not punishment Negative means removing something Remember that reinforcement increases behavior

Positive and Negative Punishment Punishment is an unpleasant consequence that leads to a decrease in behavior Positive punishment Addition of something unpleasant that decreases behavior Negative punishment Removal of something pleasant that decreases behavior

B.F. Skinner and the Experimental Study of Operant Conditioning Introduced term operant conditioning Respondent behavior classically conditioned behavior Operant behavior behavior that operates on an organism s environment to produce consequence Developed Skinner box for administration of reinforcements in animal experiments

Acquisition and Extinction Acquisition conditioning of a response Behavior increases because it is reinforced Extinction loss of a conditioned response Occurs because behavior is no longer reinforced Extinction burst- temporary increase in behavior in the absence of the reinforcer Practical applications

Schedules of Reinforcement Timing and consistency of the reinforcement affects rate at which behavior is acquired or extinguished Continuous reinforcement behavior is rewarded each time exhibited Simplest Not always feasible More vulnerable to extinction Partial reinforcement reward behavior only some of the time Ratio and interval

Ratio Schedules of Reinforcement Fixed ratio schedule Set number of responses emitted before reward given Slower extinction, high rates of responding Variable ratio schedule Exact number of responses needed to receive reward; vary around an average Even slower rates of extinction, high rates of responding

Interval Schedules of Reinforcement Fixed interval schedule Behavior rewarded once some interval of time has passed Most of responding occurs right around time reward is due with pauses after reward Variable interval schedule Similar to variable ratio, but interval varies Produces steady rates of responding Most resistant to extinction

Summary Continuous reinforcement leads to high rates of responding but the quickest extinction Ratio schedules lead to higher rates of responding than do interval schedules Variable schedules lead to behaviors that are most resistant to extinction

Discrimination and Generalization Discrimination Learns to distinguish among similar stimulus situations and to offer a particular response only in situations where reinforcement is expected Generalization Emits same behavior in response to different, but similar, stimuli Prejudice and discrimination as negative outcomes of stimulus generalization and stimulus discrimination

Shaping New Behaviors First step behavior emitted spontaneously Shaping allows a new behavior to be conditioned by successive approximations Real life examples Animal training Modifying children s behavior

Decisions That Must Be Made When Using Operant Conditioning What type of consequence? Punishment or reinforcement Punishment, especially of the harsh variety, is riskier and often less effective Choosing a reinforcer that is reinforcing Primary reinforcers are directly reinforcing Secondary reinforcers are rewarding because they lead to primary reinforcers

The High Risks of Punishment Punishment does not teach the correct/desired behavior Harsh punishment teaches aggression Harsh punishment often ineffective at producing behavior changes Harsh punishment leads to negative emotional reactions like anger, fear, and anxiety Physical punishment should be avoided

Making Punishment More Effective Tell child about appropriate behavior, then reinforce it Minimize situations that tempt bad behavior Use punisher that s aversive Punishment must occur right after behavior Punishment must occur every time behavior occurs Remain calm while punishing

The Role of Cognition in Learning Learning theories do not emphasize mental or cognitive processes Behaviorism only behavior can be studied Kohler s studies with chimps demonstrated insight learning Tolman s studies with rats demonstrated latent learning Rats developed a cognitive map or mental representation to learn

Social Learning or Modeling Learn by observing other and imitating or modeling behaviors Observational learning or modeling Different from behaviorism Acknowledges learning can occur without obvious change in behavior Acknowledges role of cognition in learning process

Albert Bandura and the Bobo Doll Experiments Social learning theory Bobo doll experiments Children watched film in which adult beat up doll then were observed interacting with own Bobo doll three conditions: adult rewarded, adult punished or no consequences for beating doll Children who saw rewards or no consequences more likely to be aggressive

Implications of Bandura s Experiments Don t have to engage in behavior for learning to occur Learning can be latent Media aggression and modeling?

Social Learning Theory and Cognition Four steps to modeling Attention must attend to behavior of model Retention must retain cognitive representation or memory of model s behavior Reproduction of behavior use memories to reproduce behavior; have physical abilities to do so Motivation must be motivated to execute behavior