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Learning: saliva A relatively permanent change in an organism’s behavior from experience How Do We Learn? ● We learn by association. Our minds naturally connect events that occur in sequence. ● Aristotle, 2000 years ago, suggested this law of association. Then 200 years ago Locke and Hume reiterated this law. Operant Conditioning: If the organism is learning associations between its behavior and the resulting events Classical Conditioning: If the organism is learning associations between events that it does not control Operant & Classical Conditioning Classical conditioning involves respondent behavior that occurs as an automatic response to some stimulus. Operant conditioning involves operant behavior, a behavior that operates on the environment producing rewarding or punishing stimuli. Pavlov: cut open dog’s cheeks to get check how much dogs salivate from being fed meat powder. Body’s natural respondent. Accidentally discovered classical conditioning. Before conditioning: neutral stimulus (bell) → dog has no response (unconditioned) Before conditioning: UC stimulus (dog food) → UC response: dog salivates During conditioning: neutral stimulus + UC stimulus = dog salivating After conditioning: conditioned stimulus (bell) → conditioned response: dog salivates CLASSICAL CONDITIONING

EXAMPLE If the aroma brewing coffee makes you feel more alert, what is the… US: coffee CS: aroma of coffee CR: feeling more alert

Little Albert Experiments: one of the first experiments in psychology (John B. Watson) Believes in Tabula Rasa Watson applied the principles of classical conditioning to humans, created emotional responses ● Watson believed that human emotions and behaviors are merely a bundle of conditioned responses (conditioned emotional reactions or CERs). ● Watson and a colleague, Raynor, conditioned a baby to associate white rats (CS) with a loud noise (US) and fear them (CR) Emotions are just responded behaviors (ex: fear, happy, sad) Acquisition: the initial stage in classical conditioning during which association between a neutral stimulus as a US takes place. The initial learning of stimulus response (S-R) relationship, as the NS and US are paired more often, the CR becomes stronger.

Extinction: the diminished CR when as US no longer follows the CS (takes time to wear off) Spontaneous recovery: reappearance of a weakened CR after a pause; this suggests that extinction suppresses the CR rather than extinguishes it.

Stimulus Generalization: the tendency to respond to stimuli similar to CS is called generalization. Pavlov conditioned the dog’s salivation (CR) by using miniature vibrators (CS) to the thigh. When he subsequently stimulated other parts of the dog’s body, salivation dropped. Something that is similar will get the same response from the experimentee. FURTHER FROM THE ORIGINAL STIMULI THE LESS OF A RESPONSE. Stimulus discrimination: the learned ability to distinguish between a CS and other stimuli that do not signal a US. Only responding to the original stimuli. High order conditioning (second order conditioning): a procedure in which the CS is one experience is paired with a different NS to create a second CS. (EX: money)

Applications of classical conditioning: Former drug users crave the drug when... 1. They are in the environment in which they took drugs. 2. They associate with people with whom they took drugs. These contexts act as CSs and trigger cravings for the drug (CR). The body only takes three days to stop being addicted to drugs (heroin, nicotine), but the CS triggers cravings (ex: cigarette burning the throat) 1. Extinction processes or new conditioning can help change unwanted responses to stimuli. 2. Exposure therapy or systematic desensitization therapy combat psychological disorders using classical conditioning principles. The immune system responds to classical conditioning: When a certain taste accompanies a drug that triggers the immune response, the taste by itself (CS) may come to trigger the immune response.

How to STUDY: Don't study on bed Start to fall asleep Or associating bed with studying which will lead to insomnia Pick a NS: most boring place on campus Do nothing but study in that room, so that room becomes associated with paying attention

Operant Conditioning: ● Associate a response (behavior) and its consequences ● Learn to repeat behaviors followed by desirable results

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Learn to avoid behaviors followed by undesirable results

Operant & Classical conditioning are both forms of associative learning

Thorndike & the Law of Effect (Edward Thorndike 1898) ● Placed cats in a puzzle box with a food reward outside the box ● Recorded the amount of time that it took to figure out how to escape ● Concluded that rewarded behavior is likely to recur, which he called the law of effect (Thorndike’s Puzzle Box) Operant Chamber: using Thorndike’s law of effect as a starting point Skinner developed the

operant chamber or the skinner box to study operant conditioning Types of Reinforcers: any event that strengthens the behavior it follows. A heat lamp positively reinforces meerkat’s behavior in the cold ● Primary reinforcers are naturally reinforcing (ex: food when hungry, taking meds when in pain, water when thirsty) ● Conditioned (secondary) reinforcers are effective through learned association with primary reinforcers (ex: money→ good grades) ● Continuous reinforcement: the desired response is reinforced every time it occurs ● Partial (intermittent) reinforcement: responses are sometimes reinforced and sometimes not (ex: gambling) Fixed-Ratio Schedules: ● Reinforce behavior after a set number of responses ● Buy 10 coffee drinks, get the 11th free ● Produces high rates of responding

● Variable-Ratio Schedules: ● Reinforce behavior after an unpredictable number of responses ● Slot machine gambling ● Produces high rates of responding

● Fixed-Interval Schedules: ● Reinforces first response after a fixed time period (every so often) ● Checking for snail mail, cramming for a test ● Produces a choppy start-stop pattern of responding

● Variable-Interval Schedules: ● Reinforces the first response after a varying time intervals (unpredictably often) ● Checking email ● Produces slow, steady responding

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Immediate Reinforcer: A reinforcer that occurs closely to a behavior in time. Rat gets food pellet for a bar press Delayed Reinforcer: reinforcer delayed in time for certain behavior. A paycheck that comes at the end of the week Punishment: an aversive event that decreases the behavior that it follows

Shaping behavior: ● Successive approximations ● Reward behavior that approaches the desired behavior ● Allows animal trainers to get animals to perform complex behaviors ● Helps us understand what nonverbal organisms perceive Stimulus Discrimination Latent learning: learning becomes apparent only when there is an incentive to demonstrate it. Cognitive maps are based on latent learning which becomes apparent when incentive is given. Ex: Tolman and Honzik, 1930 Cognitive map: a mental representation of the physical features in the environment Observational Learning: ● Learning by observing others ● Learning by imitating models ● Learning without direct experience Modeling: ● Observing and imitating specific behaviors Bandura’s Experiments: Bandura’s bobo doll study (1961) indicated that children learn through imitating others who receive reward and punishments Learning by observation: higher animals especially humans learn through observing and imitating others. Ex: Monkey on the right imitates monkey on the left touching pictures in a certain order to get a reward Mirror Neurons: ● Neurons in the frontal lobe that fire when performing certain actions or observing others perform those actions ● Enable imitation and empathy ● Underlie humans’ social nature Television and Observational learning: gentile et al. (2004) showed that elementary school going children who were exposed to violent television, videos, and video games expressed increased aggression Modeling violence: research has shown that viewing media violence does lead to increased expression of aggression Positive Observational Learning: the good news is that prosocial (positive, helpful) models can have positive effects

Memory: iconic Myers: make things memorable What is memory? ● Learning that has persisted over time ● info that has been stored over time ● Info that can be retrieved over time Three-Stage Model of Memory:

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Sensory input from the environment is recorded as fleeting sensory memory Info is processed in short-term memory Info is encoded into long-term memory for later retrieval

● Sensory Memory

The briefest form of memory storage: sensory memory The immediate, initial recording of sensory info in the memory system Visual: iconic memory ● Demonstration: sperling's photographic recall test ● Duration: less than a second Auditory: echoic memory ● Duration: a few seconds ● Ex: last few words of a sentence Sensory Memory: ● Major function is to hold info long enough to be processed further ○ Sensory registers ● Helps us to experience a constant flow of info, even if that flow is interrupted ● Selective attention: mental resources are focused on only part of the stimuli around us ○ Remaining sensory memories fade quickly Iconic Memory: ● A fleeting photographic memory Whole report: The exposure time for the stimulus is so small, that items cannot be rehearsed sperling (1960) Partial report: sperling argued that sensory memory capacity was larger than what was originally thought Sensory Memory: the longer the delay the greater the memory loss Sensory memories: duration of sensory memory differs for different senses

Working memory:

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Alan baddeley (2002) proposes working memory to contain auditory, visual processing controlled by central executive, through episodic buffer

Capacity of Short-term memory: ● Immediate memory span: max number of times one can recall after one presentation ● Miller’s (1956) “magic number”: 7 plus or minus 2 chunks of info Rehearsal: ● Effortful learning usually requires rehearsal or conscious repetition ● Ebbinghaus studied rehearsal by using nonsense syllables: TUV YOF GEK XOZ Duration: brown/peterson and peterson measured the duration of working memory by manipulating rehearsal Duration of working memory is about 20 sec Serial position experiment: ● Get out a blank sheet of paper and pen ● View 20 words appearing on the screen ● There will be a break of 90 sec

Information overload: ● We live in a world with 300 exabytes (300 billion billion) of info ● Processing capacity of the conscious mind is only about 120 bits per second ● Unproductively and loss of drive can result from decision overload

Dual-Task interference: ● Phenomenon that occurs when two tasks are attempted simultaneously ○ Ex: when people do two cognitive tasks at once, their cognitive capacity can drop from that of a harvard MBA to that of an eight-year-old Getting the “gist” of it: ● Only 50 bits of info/second make their way into the conscious brain, eleven million bits of data flow from the senses every second ● All of us regularly rely on the “gist” of things in our reasoning ● Dual-process theory: associative vs true reasoning- system 1 vs 2

The fact that you have to be slower when you take notes by hand is what makes it more useful in the long run Not A “Stream” of consciousness ● “Stream” of consciousness illusion, we actually perceive the world in rhythmic pulses rather than as a continuous flow ● Possibility that brain rhythms are not merely a reflection of mental activity but a cause of it ● Brain samples the world in rhythmic pulses, even discrete time chunks, much like the individual frames of a movie ○ Wagon wheel illusion: spokes on a wheel are sometimes perceived to reverse the direction of their rotation A life of meaning/reasoning? ● Fundamental neurological reality: a visceral sense of meaning in one’s life is an involuntary mental state that, like joy or disgust, is independent from and resistant to the best of arguments ○ Our feelings are generated from different parts of our brain than reasoning, feelings happen first ○ Reason provides an after-the-fact explanation for moral decisions that are preceded by inherently reflexive positive or negative feelings ○ Studies have confirmed that the conscious sense of willing an action...is preceded by subliminal brain activity likely to indicate that the brain is preparing to initiate the action ○ The conscious mind controls our brain only 5% of the day. The subconscious mind holds our thoughts 95% of the time How to improve memory? ● Use distributed (spaced) practice ● Make the material meaningful. ● Activate retrieval cues.

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Use mnemonic devices. Minimize interference. Sleep more. Test yourself!

Proactive Interference ● Forward acting ● The disruptive effect of prior learning on the recall of new information ● A friend’s email address that was learned long ago may interfere with learning the new email address.

Retroactive Interference ● Backward acting ● The disruptive effect of new learning on the recall of old information ● Learning a password for a new bank card can disrupt recall of the password for your existing ATM card.

Interference & Forgetting

Forgetting: Retrieval Failure ● Tip-of-the-tongue phenomenon ● Interference ● Motivated forgetting Storage Decay ● Memories decay gradually if they are not used. ● Information is at first rapidly forgotten. ● After a certain period of time, the forgetting levels off. Encoding Failure ● Information is never encoded into long-term memory. ● What letters accompany the number 5 on the telephone? ● Where is the number 0 on your calculator? ● Some memories cannot be encoded without effort.

Moods and Memories -Tendency to recall experiences that are consistent with one’s current mood. Emotions, or moods serve as retrieval cues. Context Effect: State-Dependent Memory

Recall is improved when encoding and retrieval of a memory happen in the same emotional or biological state. ● It is difficult to remember happy times when depressed. ● This may explain why after a happy experience, people view the world through rosecolored glasses. Context Effects -Scuba divers recalled more words underwater if they learnt the list underwater, and recalled more words on land if they learned the list on land (Godden & Baddeley, 1975).

False Memory ● False memories can be “planted.” ● Imagining nonexistent events can create a memory. ● Imagination inflation – Imagining something and really perceiving it activate similar brain areas. ● People with vivid imaginations are more likely to have false memories. ● Children are very susceptible to false memory. Misinformation Effect ● Incorporating misleading information into the memory of an event ● Elizabeth Loftus asked: § “How fast were the cars going when they hit each other?” ● “How fast were the cars going when they smashed into each other?” ● The reported recall of the rate of speed depended on how the question was asked.

The Effect of Schemas on Recall

Retrieval: Getting Information Out Retrieval Recall—bringing previously learned information into conscious awareness, as in a fillin-the-blank question on a test Recognition—correctly identifying previously learned information when exposed to it again, as in a multiple-choice test Retrieval Cues- Memories are held in storage by a web of associations. These associations are like anchors that help retrieve memory.

Cerebellum- a neural center in the hindbrain that processes implicit memories. ● Crucial to the formation of implicit memories ● Plays key role in forming and storing memories created by classical conditioning ● Damage to cerebellum disrupts forming conditioned reflexes. Implicit Memory -HM is unable to make new memories that are declarative (explicit) but he can form new memories that are procedural (implicit). -HM learnt the Tower of Hanoi (game) after his surgery. Each time he plays it he is unable to remember the fact that he has already played the game. Amnesia Retrograde—Inability to access memory before a certain date Anterograde—Inability to form or consolidate new memories

after a certain date The Hippocampus ● Processes explicit memories for facts and episodes ● Feeds memories to other brain areas for storage ● Part of the limbic system ● Active during slowwave sleep ● Hippocampus and cortex display simultaneous activity during sleep. Storing Implicit & Explicit Memories Explicit Memory refers to facts and experiences that one can consciously know and declare. Implicit memory involves learning an action, and the individual does not know or declare what she knows.

Emotional Memory ● Can be persistent ● Heightens the body’ s stress response ● Spurs production of the stress hormones adrenaline and cortisol ● Can be a key symptom of Post-traumatic Stress Disorder (PTSD) ● Experimental treatments include drugs to block memory. Flashbulb Memories ● Flashbulb memories are clear, detailed memories of emotionally significant events. ● How do such memories get encoded? What parts of the brain are involved? Emotion & Memory Excitement, stress, or strong emotion can strengthen memories. Stronger memory in response to emotional situations is adaptive. ● Emotion-triggered stress hormones increase glucose production, which signals to the brain that something important has happened. The amygdala boosts activity and proteins in the brain’ s memory areas. LTP is a physical basis for memory ● LTP-blocking drugs interfere with memory. ● Mice that lack an enzyme needed for LTP cannot navigate a maze.

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Injecting rats with a chemical that blocks LTP erases recent learning. Rats that ingest an LTPenhancing drug learn a maze with half the number of usual mistakes.

Synaptic Changes- Kandel and Schwaru (1982) Showed, in Aplysia, that serotonin release increased from neurons after conditioning. Studying Long-term Potentiation • Through experience, the slug withdrew its gill more quickly. • More serotonin was found in its synapses. • What was occurring: strengthening of neural firing, also called long-term potentiation (LTP)....