Lecture 6 - Learning

Learning Random Selection (before the experiment, not using to control factors) vs Random Assignment (don’t want a characteristic of the people to interfere with the independent variable, extraneous variable) Learning is a: relatively permanent change (flexible in how permanent) ● In behavior (can show if truly learned through behavior) ● result of experience that leads to certain way rather than just watching ○ Ex. Almost car crashing when texting, so learns to look before texting Ivan Pavlov (1849-1936): Pavlov’s Dogs to measure saliva based on what food is present in only a laboratory. When getting dogs ready, the dogs already salivate (Problem) like having food in front. (prediction) an association with food and lab people ● Classical Conditioning: “natural reflex” of saliva when food is placed. Learning to make involuntary response to stimulus other than the original, natural stimulus that normally produces the response ● Unconditioned Stimulus (UCS): “unlearned” naturally occurring stimulus ● Unconditioned Response (UCR): “unlearned” automatic response from UCS ● Neutral Stimulus (NS): no effect on desired response prior to conditioning ● Conditioned Stimulus (CS): previously neutral stimulus that produces a “learned” conditioned response after pairing to an unconditioned stimulus ○ Ex. Moving dog food dish, so dog acts excited as the dish became CS NS = CS ● Conditioned Response (CR): learned response to a conditioned stimulus ○ A stimulus is any object, event, or experience that causes a response ○ An unconditional stimulus (US) leads to an unconditional response (UR) ■ Unlearned stimulus of food to salivation (ex. Blinking) ○ The Conditional stimulus (CS) starts out neutral ■ The people come in and the dogs have no response and only salivates with the food ■ becomes associated with US after repeated pairing. Starts salivates with people as they connect the people to food CS – US – UR ■ The paring becomes strong when CS evokes conditioned response (CR) without the US present CS – UR/CR Pavlov’s Classic Study: dog presented with only meat powder to let the dog salivate but not get full. Metronome started beforehand that acts as a neutral stimulus. Eventually, metronome without powder follows but dog salivates still. Metronome starts as neutral but turns into conditional. ● Food is the stimulus and salivation is the response, Metronome ticking is the neutral stimulus before any conditioning took place. Paired this to UCS (Acquisition) as organism is acquiring learning 1. CS must come before UCS. If metronome was given after food, no conditioning 2. The CS and UCS must be close together in time (5 secs) or no association due to a longer interval so there could be extraneous factors 3. NS paired with UCS many times before conditioning 4. CS is distinctive or stands out from other stimuli. The metronome was distinct as it wasn’t usually present in the lab Ex. Dentist. Body associates sound (CS) with anxiety (UCR) during painful treatment (UCS) so the sound produces anxiety (CR) in any area at the dentist office Stimulus Generalization: tendency to response to a similar stimulus to the original CS with the CR. generates a CR to a stimulus like the CS ● Ex. Train dog to salivate to bell, and still will but less to diff bell sound ● Further away from original stimulus, the less effect generated ● Ex. Beng scared by a dog, then becomes scared of all types of dogs Stimulus Discrimination: tendency to stop making a generalized response to a similar stimulus due to the similar stimulus never paired with the UCS. responding with CR only to the CS, not similar stimuli ● Ex. Train dog to salivate to bell, but not give food with diff bell sound Extinction: disappearance/weakening of a learned response when UCS or reinforcer is removed reduction in CR after frequent non-pairing US & CS ● Ex. Not give food to dog even after bell Spontaneous Recovery: reappearance of CS to CR even after extinction ● Takes 3x longer to rid of useful association than it is to create it Higher-Order Conditioning: strong CS paired with NS, causing NS to become a second CR ● New stimulus NS – CS – UR/CR (not easy to do, lower response level) ● Ex. Nausea medicine as stimulus tied to violence to feel sick Stimulus Substitution: CS activates the same brain area originally activated by UCS thus the CR and UCR produce a similar response UCS/CS - response Biological Preparedness: many rats developed a conditioned taste aversion to certain foods only after 1 trial Robert Rescorla: CS must predict the UCS to achieve conditioning ● 1 rat group to a tone then followed a shock. Agitated and fear with tone = CR ● 1 rat group to a tone then gave a shock AFTER tone stopped. No fear of tone ● Showed that there was a particular expectancy of this pairing for the CR, and is example of a classical conditioning explanation: Cognitive Perspective Taste Aversion (Garcia): development of nausea/averse response to particular taste because the taste was followed by a nausea reaction, only after one association Ex. Drug dependency due to the “high response” as body is classically conditioned to associate drug use with cues ● Single-Trial Conditioning: rats drink tasty drink and is irradiated which makes them sick. Later, rats given access to tasty drink but avoids it (classical conditioning) The Tragic Tale of Little Albert (John Watson): conditioning a rat phobia. Starts with presenting animals and pet them, neutral. But then whenever the boy pet the white rat, there was a loud noise, which scared the baby many times. Conditioned fear whenever saw a white rat, but also afraid in similar objects (ex. Rabbit, dog, furry objects) ● NS: white rat, UCS: naturally scared of loud noise, UCR fear of noise, CS white rat, CR rat phobia Conditioned Emotional Response (CER): emotional response that is classically conditioned with learned stimulus Vicarious Conditioning: classical conditioning of an involuntary response/emotion by watching the reaction of another person (ex. Mother afraid of spiders so daughter is too)