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Learning & Memory Learning • Change in behavior or mental processes due to experience • Allows us to adapt to our environment Learning • Association - connection between events that occur together – Classical conditioning – Operant conditioning – Observational learning • Learning is flexible Classical conditioning • Ivan Pavlov – Studying digestive reflexes • Classical conditioning – Learning an automatic association between two stimuli – Response is reflexive Classical conditioning • Requires the pairing of two stimuli to condition a response – Stimulus • Neutral stimulus • Unconditioned stimulus – Response • Unconditioned response Classical conditioning Food Unconditioned Stimulus Salivation Unconditioned Response This is an unlearned (unconditioned) association Classical conditioning Bell (Neutral Stimulus) Food Salivation Unconditioned Stimulus Unconditioned Response • If you pair a NS with UCS a number of times… Classical conditioning Bell (Conditioned Stimulus) Salivation (Conditioned Response) • It will begin to elicit a conditioned response Classical conditioning • Extinction • Spontaneous recovery Classical conditioning • John Watson & Little Albert – UCS – UCR – CS – CR Classical conditioning outside the lab • • • • Advertising PTSD Aversions Phobias Classical conditioning review + Neutral stimulus Unconditioned stimulus Unconditioned response Conditioned stimulus Conditioned response Operant conditioning • Association between a behavior and a consequence E.L. Thorndike • Puzzle box paradigm – Learning curve for escape • Law of effect – Successful behaviors are likely to be repeated B.F. Skinner • Major pioneer of behaviorism – All responses can be scientifically measured • Skinner box – Used to shape complex behaviors Learning and association between a response and a consequence • Consequence must follow a behavior • Reinforcement - increases the likelihood of the response + – Positive reinforcement • Adds something desirable – Negative reinforcement - • Takes away something unpleasant • Punishment - decreases the likelihood of the response – Positive punishment + • Adds something unpleasant – Negative punishment - • Takes away something desirable Consequences • Reinforcement – Primary reinforcers - innately satisfying – Secondary (conditioned) reinforcers - associated with satisfaction • Punisment – Not simply the opposite of reinforcement – Creates several unwanted side effects • Suppresses all behaviors • Creates fear • Teaches/increases aggression & cruelty Reinforcement schedules • Affect speed and retention of learning • Continuous reinforcement • Partial reinforcement – Fixed ratio – Variable ratio – Fixed interval – Variable interval Shaping • Complex behaviors are created by reinforcing successive approximations of the desired behavior – Each response that comes closer to the desired behavior is rewarded – Discrete segments of the behavior eventually comprise the whole behavior Applications of operant conditioning • Behavior modification – Applied behavioral therapy – Animal training – Teaching children good behaviors and basic skills – Increasing employee productivity Extinction • In the absence of a consequence, conditioned behavior will diminish – Following extinction, the learned behavior may be recovered Classical and Operant conditioning • Contrast – Classical conditioning creates an automatic response – Operant conditioning teaches an association between behavior and consequence • Compare – Associative learning Observational learning • Animals and humans learn through watching and imitating others • Part of typical development Observational learning • Observational learning utilizes mirror neurons – Neurons in the frontal cortex – Respond to observation of activity and emotion Albert Bandura • Observational learning relies on watching another’s behavior and observing the outcome • Bobo doll study Observational learning • Modeling/observation of prosocial behaviors increases the occurrence of those behaviors • Modeling/observation of negative behaviors can have antisocial effects – Children exposed to violence are more aggressive – Television is a model of many negative behaviors • Correlation • Causation – Effects of media violence on attitudes and behaviors • Immitation • Desensitization Memory • The persistence of learning over time. • Nondeclarative memory – Perceptual – Procedural – Stimulus-response • Declarative memory – Episodic – Semantic 3 steps to form a memory Encoding Analogy: New sweater • Fold the sweater and put it away in the closet Storage • Sweater sits in the closet Retrieval • Take the sweater out to wear it 3-stage memory model • Sensory memory - limited sensory record – Some information is automatically encoded • Working memory (short-term memory) - active encoding – Processes new information – Utilizes and modifies previously stored memories – “Active” component of memory • Long-term memory - encoded and stored Encoding • Processing information into memory • How we encode – Automatic encoding - requires little effort or conscious awareness • Space - visual maps • Time - sequence of events • Frequency - repetition of events – Effortful encoding - requires attention and effort • Rehearsal Ebbinghaus - rehearsal studies • The amount of information remembered depends on the amount of time spent learning Effects on encoding • Serial position effect – Primacy • Following a delay – Recency • Immediately after learning • Spacing effect • Small, repeated rehearsals improve retention • Effortful processing often becomes automatic with rehearsal Encoding • What we encode – Semantic encoding - meaning – Visual encoding - imagery – Organization • Chunking • Hierarchies Storage • Retention of memories in the brain • Stages of Memory – Sensory memory – Working memory – Long-term memory Sensory memory • Sensory information trace – Remains in the sensory system momentarily – May be encoded into a short-term memory • Iconic memories - visual – ½ second • Echoic memories - auditory – 3-4 seconds Working memory • The mid-stage of memory storage – Short-term memories + recalled long-term memories – Consciously aware of our memories and can work with them at this stage • Sensory memories short-term memories – Incoming memories must be rehearsed to be maintained Working memory • Working memory has a limited capacity – 7 +/- 2 pieces of information – 20 seconds • Capacity extended by – Chunking – Rehearsal Long-term memory • Encoded and stored memories • Essentially unlimited capacity Storing memories • Formation of long-term memories relies on neural changes – – – – Long-term potentiation Not an exact replica Not located in one spot in the brain Brain damage has varying impact, due to the nature of memory storage Memory and stress • High stress and strong emotions fuel brain activity • Flashbulb memories – Reliable – Not completely infallible Where are memories made? Retrieval • Getting information out of long-term storage • Memories are stored in a network of related information – Retrieval cues • Memory associations are activated by conscious and unconscious events – Priming – Context • Déjà vu - sensation of reliving a previously experienced situation – Emotions • State-dependent memory Forgetting • Inability to retrieve information – Can happen at any memory stage • Encoding failure – Information not encoded at any stage will be forgotten – Encoding affected by • Age • Arousal • Mood Anterograde amnesia • Inability to for NEW declarative memories – Failure of encoding – Due to hippocampal damage Forgetting • Storage decay – Encoded, stored memories may be lost – Forgetting curve • Less durable memories are lost most easily Retrograde amnesia • Large-scale loss of previously stored memories – Due to brain injury – Time frame of loss varies – Often temporary Retrieval failure • Some memories are not readily retrieved from storage – “Tip of the tongue” phenomenon • Interference – Proactive interference – Retroactive interference • Revision Memory is a constructive process • Schemas – New memories are fit into existing belief structures – Assimilation – Accommodation Memory is a constructive process • Memory recall is not an exact replica of original events and information – Recall is a reconstructing of memory based on: • • • • • New experience, ideas, information Alteration in the strength of some memories Interaction with others Filtering out information Filling in missing pieces Memory is a constructive process • Memory is influenced by faulty information • Misinformation effect – Loftus’s research on false memories • Imagination – We can create our own false memories Memory is a constructive process • Eyewitness recall - not as reliable as once thought! – Children’s recall – Adult recall • Final thought: Memory is a reconstructive process and confidence is NOT correlated with accuracy!
