Ch.5 Classical Conditioning" Underlying Process/ practical applications

Introduction

• How classical Conditioning works

  • Stimulus-Substitution Theory

  • Preparatory-Response Theory

  • Compensatory Response Model

  • Rescorla-Wagner Theory

• Practical Applications

  • Understanding Phobias

  • Classical Treatments for Phobias

  • Hybrid Treatments for Phobias

  • Aversion Therapy

  • Medical Applications

(Stimulus- Substitution Theory)

• CS acts as (substitute )for US

  • Example: Pairing a tone with food = tone becomes substitute for food & tone can now elicit salivation

• If CS is acting as a substitute for the US, then CR should always (be the same), or at least highly (similar), to the UR

• But … sometimes this is not the case. Possible substantial differences between the CR and the UR

Review of Stimulus-substitution theory

• Food→ activates food in center cortex→ activates salivation center in cortex→ Salivation

• Light→ activates light center in cortex →activates food center in cortex→ activates salivation center in cortex→ Salivation

(Preparatory- Response) theory of conditioning

• Purpose of the CR is to (prepare)the organism for presentation of US

  • Example: Dog salivates to the tone to get ready for food; rat freezes in response to light to get ready for the shock

  • Unlike stimulus-substitution theory, preparatory response theory allows for situations in which CR and UR are (sometimes different)

(Compensatory- response)

• Model and Implications for Drug Addiction

• Drug addictions are partly motivated by a tendency to (avoid the symptoms of withdrawal); compensatory responses to drug effect

  • Example: Heroin = decrease in blood pressure, etc., which drug user experiences as pleasant feelings of relaxation and euphoria. This relaxing effect of heroin in turn elicits compensatory reactions that, on their own, would be experienced as unpleasant feelings of agitation.

    • Heroin→ decreased blood pressure (a-process) → increased blood pressure (b-process)

• After repeated heroin use, addict experiences unpleasant feelings of (agitation)simply being in presence of heroin-related cues. Symptoms = what the addict perceives as cravings or symptoms of withdrawal

• Often impossible to completely avoid all cues associated with the drug. Modern treatments for drug addiction often include procedures designed to extinguish the power of drug-related cues

• Many “overdose” fatalities (do not), (in fact), involve an unusually large amount of the drug

  • Example: Heroin addicts often die after injecting a dosage that (has been well tolerated) on previous occasions. Critical factor = setting where drug is administered

(Rescorla-Wagner)Theory

• Definition

  • US can support(only so much conditioning), and this amount of conditioning must be distributed among the various CSs present.

  • There is only so much (associative value) available to be distributed among the cues associated with the US.

  • (Contradicts) general rule that the presentation of the CS without the US will result in extinction

• (Over expectation) effect

  • Decrease in conditioned response occurs when (2)separately conditioned CSs are (combined) into compound stimulus for further pairings with the US

Understanding Phobias

• Phobias require only (1 pairing) of the CS with the US to become established.

• Phobias grow (stronger)over time.

• Many people with phobias are (unable to recall any particular conditioning event) before the development of their symptoms.

• Observations: Phobias acquired when (observing)fearful preparedness

• Temperament: Level of emotional reactivity, usually (genetically determined)

• Preparedness: Disposition to learn certain types of (behaviors) or certain types of (associations) more easily

  • Rat(NS): Loud noise (US)→ Fear(UR)

  • Rat(CS)→ Fear(CR) as indicated by crying and crawling away from rat

• Exposure to a US of a (different intensity) than used during conditioning can (alter)the strength of the response to a previously conditioned CS. (Example: major vs minor injury)

  • Be particularly careful in regards to the sort of information conveyed to people who have suffered potentially traumatic events, because that information itself might induce a traumatic reaction

• (incubation)–strengthening of conditioned fear response as a result of brief exposures to an aversive CS

• (Selective Sensitization)–increase in one’s reactivity to potentially fearful stimulus following exposure to an unrelated stressful event (Example: divorce and fear of traffic)

Classical Treatments for phobias

• Phobias are highly susceptible to treatments based on behavioral principles of conditioning.

• (Systematic Desenitization)–process succession of stimuli that elicit increasing levels of fear

• Steps:

  • Training in (relaxation)

  • Creation of a hierarchy of 10-15 imaginary scenes that elicit (progressively intense levels of fear)

  • Pairing of each item in the hierarchy with relaxation

    • (Counterconditioning)- CS that elicits one type of response is associated with an event that elicits an incompatible response

    • (Reciprocal Inhibition)–Occurrence of one response can be inhibited by the occurrence of an incompatible response

• (flooding)–prolonged exposure to a feared stimulus providing maximal opportunity for conditioned fear response to be extinguished

• (Imaginal Flooding–client asked to visualize, as clearly as possible, a scenario involving the feared event. The greater the level of fear induced by the visualized scenario, the better!

• (in Vivo Flooding) –Example: Fear of balloons? Fill room with balloons. Client enters the room, closes the door, and remains inside for an hour or more. Fear is eliminated after a few sessions.

(Hybrid) treatment for phobias

• Hybrids can be (more )effective than systematic desensitization or flooding alone

• Single session to eliminate phobias = In vivo exposure in which clients were encouraged to approach the feared spider as closely as possible, remain there until the anxiety faded away, and then approach the spider even more closely. This process continued until the client had closely approached the spider and had experienced at least a 50% reduction in reported level of fear

  • Similar to systematic desensitization because somewhat (gradual)

  • Similar to flooding because client encouraged to endure a fairly intense level of anxiety each step of the way

• Participant (modeling)/contact desensitization has also been shown to greatly facilitate treatment.

(Aversion Therapy) for problem behaviors

• Treatment procedure that reduces the attractiveness of desired event by associating it with aversive stimulus

• (Relapse Prevention)–person learns to identify and cope with situations in which there is a high risk of resuming the problematic behavior

• (Covert Sensitization)–aversion therapy sometimes carried out with imaginal stimuli rather than real stimuli

Medical Applications of classical conditioning

• Allergic to pollen?

  • Even the mere (Sight)of flowers might elicit allergic reaction

    • Flowers(NS): Pollen(US)→ Allergic reaction(UR)

  • (placebo effect)–result of pairing appearance of drug (originally NS) with active ingredients of the drug (the US)

    • White pill(NS): Acetylsalicylic Acid(US)→ Headache removal (UR)

    • White pill(CS)→ headache removal(CR)

Summary

• How classical Conditioning works

  • Stimulus-Substitution Theory– CS acts as substitute for US

  • Preparatory-Response Theory– CR prepares organism for presentation of US

  • Compensatory Response Model–a-process/b-process

  • Rescorla-Wagner Theory–only so much associative value available to be distributed

• Practical applications

  • Understanding Phobias– Phobias require one pairing of the CS with the US to become established.

  • Classical Treatments for Phobias–Systemic Desensitization and Flooding

  • Hybrid Treatments for Phobias–Single Session and Modeling

  • Aversion Therapy–reduces attractiveness of desired event by associating it with aversive stimulus