Conditioning and Learning Exam 2 Chapter 3 Cause and effect relationships in the world ensure that certain things occur in combination with others You cannot walk through a doorway unless the door was first opened Social institutions and customs also ensure that events occur in a predictable order Classes are scheduled at predictable times Learning to predict events in the environment and learning what stimuli tend to occur together are important for aligning behavior with the environment The simplest mechanism whereby organisms learn about relations between one event and another is classical conditioning Pavlov and Edwin Twitmyer separately discovered classical conditioning Pavlov researched digestion developed surgical techniques that enabled dogs to survive for many years with artificial fistulae that permitted the collection of various digestive juices Awarded the Nobel Prize in Psychology in 1904 Assistants in the lab referred to stomach secretions elicited by food related stimuli as psychic secretions because they seemed to be a response to the expectation or thought of food S G Vul fson and A T Snarskii first systematic studies of classical conditioning used dry food wet food sour water and sand after the dogs had these substances placed in the mouth repeatedly the mere sight of the substances was enough to make them salivate Snarskii used artificial substances black sour water plain black water they salivated to Orosensory Stimuli texture and taste sensations in the mouth Object Learning learning associations between different stimulus elements of an object Conditional or Conditioned Stimulus CS A stimulus that does not elicit a particular response initially but comes to do so as a result of becoming associated with an unconditioned stimulus the tone Unconditional or unconditioned Stimulus US a stimulus that elicits a particular response without the necessity of prior training the food Conditional or Conditioned Response CR the response that comes to be made to the conditioned stimulus as a result of classical conditioning the salvation from the tone Unconditional or Unconditioned Response UR a response that occurs to a stimulus without the necessity of prior training the salvation that was always elicited by the food Pavlov worked with dogs Watson and Rayner believed that infants are at first limited in their emotional reactivity conditioned a fear response in a nine month old infant Albert to the presence of a docile white laboratory rat each conditioning trial consisted of presenting the rat to albert and then striking the steal bar At first albert reached out to the rat when it was presented to him after 2 trials reluctant to touch the rat after 5 more trials strong fear responses to the rat Albert shows fear by whimpering and crying rats show their fear by freezing a species typical defense response that occurs in a variety of species in response to the anticipation of aversive stimulation Conditioned Emotional Response Conditioned Suppression Suppression of positively reinforced instrumental behavior lever pressing for food pellets caused by the presentation of a stimulus that has become associated with an aversive stimulus if a fear CS tone is presented their licking behavior is suppressed and they take longer to make a specified number of licks Estes and Skinner once the rats are lever pressing at a steady rate fear conditioning is introduced consisting of a tone or light paired with a brief shock As to suppress the participants acquire the conditioned fear they come their lever pressing during the CS Lick Suppression Procedure Similar to the conditioned emotional response however instead of lever pressing for food serving as the behavior that is suppressed by conditioned fear the baseline is licking a water spout by thirsty rats The presentation of a fear conditioned CS slows down the rate of drinking Suppression Ratio CS responding CS responding pre CS responding Suppression Ratio has a value of zero if the rat suppresses lever pressing completely during the CS because in this case the numerator of the formula is zero At the other extreme if the rat does not alter its rate of lever pressing at all when the CS is presented the ratio has a value of 0 5 conditioned suppression data scale is inverse the smaller the suppression ratio the more emotionless the animal is because the CS elicits more conditioned fear Eyeblink Conditioning If the air puff is preceded by a brief tone the person will learn to blink when the tone comes on an anticipation of the air puff Five month old infants CS 1 000 cps tone presented for 750 milliseconds US gentle puff of air delivered to the right eye through a plastic tube Group 1 CS always ended with a puff of air conditioning trials occurred 12 seconds apart Group 2 same and distribution of CS and US presentations CS s and US s were spaced 4 8 seconds in an explicitly unpaired fashion this was the control group paired group responded to the CS at a significantly higher rate from the beginning of the second session Classical conditioning required the pairing of a CS and US Rabbit Eyeblink developed by Gormezano required several hundred trials because the conditioning is slow Sign Tracking Autoshaping movement toward and possibly contact with a stimulus that signals the availability of a positive reinforce such as food animals tend to approach and contact stimuli that signal the availability of food In the natural environment the availability of food can be predicted by some aspect of the food itself such as its appearance at a distance Brown and Jenkins used pigeons the birds were given access to food for a few seconds The key light was illuminated for 8 seconds immediately before each food delivery Instead of using the key light to tell them when to Presenting pecking light go to the food dish the pigeons started pecking at the key itself the keylight at random times or unpaired with food does not lead to The food cup was located 3 feet from the light the pigeons went to the rather than the food cup when the CS was presented Rozin and Zellner A conditioned taste aversion is learned if ingestion of a novel flavor is followed by an aversive consequence such as indigestion or food poisoning The typical aversion learning experience involves eating a distinctively flavored food and then getting sick Taste aversion learning is a result of the pairing of a CS a taste and a US drug injection or radiation exposure in much the same manner as
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