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Lecture 4: Classical Conditioning in Humans 1/ Watson and Little Albert 2/ Classical conditioning and treatment of phobias 3/ Aversion therapy 4/ Classical conditioning and Awareness Is it necessary? 5/ Classical conditioning and advertising John B Watson (1878-1958) Watson & Rayner (1920) A loud noise elicit s a fear reaction (crying and other fear-like responses) Little Albert: conditioned to a white lab rat paired with loud noise When playing with rat experimenters would strike a steel bar with a hammer behind Albert’s head Little Albert began to show fear to the rat (crying and crawling away) 1 Treating Phobias Mary Cover Jones (1924) student of Watsons Used classical conditioning to reduce fear reactions. Example: Peter, a toddler with a fear of rabbits She used counterconditioning on Peter Counterconditioning z One CS is presented at the same time as another event, that elicits an incompatible response ¾ Jones (1924) brought a rabbit (CS that elicits anxiety) into the same room but far away from Peter while he was eating his cookies and milk snack (CS that elicits good feelings) ¾ Jones did this each day and gradually brought the rabbit closer and closer until there was no fear to the rabbit (eventually the rabbit was put into his lap!) ¾ Treating Phobias Systematic Desensitization (Joseph Wolpe,1958) Start by getting person to be relaxed Create hierarchy of fear eliciting stimuli from least to most strong example of stimulus Gradually (from least to most) pair each item of hierarchy with relaxation without producing fear (because of deep relaxation) combines counterconditioning, generalization, and extinction e.g. Early on the hiearchy would consist of imagining events – slowly Move to more threatening situations 2 Treating Phobias Example: Patient with a fear of snakes Start off imagining a snake Look at pictures of snakes Look at a toy snake Handle a toy snake Be in the room with a snake in the cage ..Eventually handling snake putting it around his/her neck! Systematic desensitization Davison (1968) Subjects with intense fear of snakes 13-step test to assess their initial fear – involving progressively More exposure to the snakes. Ranging from approaching a Snake in a jar – to touching the snake for 30 seconds. 4 Groups: 1/ Systematic desensitization – progressively more aversive scenes involving snakes – paired with relaxation exercises. 2/ Imagined disturbing childhood scenes – paired with relxation 3/ Imagined snakes as in 1/ but no relaxation 4/ No treatment: control group Systematic desensitization group only group to show significant Improvement. 3 Systematic desensitization Paul (1969) conducted a study with students that had severe anxieties about public speaking Had 3 treatment groups: 1/ Systematic desensitization group 2/ Psychotherapy group 3/ No treatment control group Assessment 2 years later: 85% in the systematic desensitization group showed significant improvement compared to pre-treatment levels 50% showed improvement in the psychotherapy group Only 22 % in untreated control group Effectiveness of systematic desensitization varies according to phobia But.. one of the more successful treatment options for some phobias. Flooding Drop patients in at the deep end! Expose them to fear provoking stimulus at full intensity. Eventually they should start to extinguish their fear. But this is extremely stressful. Rothbaum (1995) used virtual reality technology to provide exposure to the feared stimulus Used VR to present subjects with fear of heights with realistic scenes involving heights: walking on foot bridges, outdoor balconies, riding up a glass elevator Marked reduction in fear of heights – equivalent to actual flooding using real heights. 4 Counteracting Conditioned Taste Aversion Broberg & Bernstein (1987) Children undergoing chemotherapy would develop taste aversions to the meal they had that day. Gave the children a distinctive-flavored Lifesaver candy (CS) between their evening meal and the chemo session (US) and found that 12 of 15 children ate the food at the meal again later On another occasion the same children were not given the Lifesaver candy between the evening meal and chemotherapy, and they found that only 6 of the 15 children would eat that meal again Aversion Therapy Pair the problem behavior with an aversive stimulus As an association forms the attractiveness of the problem behavior is reduced Example: Raymond (1964) Used aversion therapy to help a 14 year old boy stop smoking Gave injection of apomorphine Then told to start smoking 11 minutes later became naseated and vomited. 4 days later came for treatment – reported felt nauseated when he tried to light one Two months later – felt nauseated when offered a cigarette No longer smoked 1 year after treatment 5 Another example Tiffany et al., (1986) Used smoking itself as the aversive stimulus to give up smoking. Smokers asked to smoke rapidly and inhale deeply every 6 seconds – continue smoking for 3 minutes or until they felt unable to continue. Rapid smoking led to nausea. 6 months treatment: 59% patients no longer smoked compared to control groups Other studies did not work so well Tried pairing smoking or alcohol with shock – with little success. Another problem – even though treatment may be successful in laboratory, patients often relapsed when they went home. Why might these methods not have succeeded as well as they might? Biological preparedness Discrimination 6 Other approaches Psychodynamic (Freudian) Cognitive-Behavioral therapy Therapists focus on peoples cognitions as well as their behaviors e.g. fear of public speaking may be associated with ‘irrational’ cognitions – assumption of ridicule, catastrophisation etc. Therapy could be a combination of confronting those ‘irrational thoughts’ and behavioral modification to reduce fear. Pharmacological e.g. administration of anxiolytics or antidepressants (beta blockers, benzodiazapenes, SSRIs) Classical conditioning and advertising Smith and Engel (1968) Showed 120 subjects a picture of an automobile. For half the subjects – photograph only showed the car Others – car was paired with attractive female model Subjects in 2nd group – rated car as better along a number of dimensions and also more expensive (as well as less safe). Subjects denied that model influenced their judgment 7 Classical conditioning and advertising Gorn (1982) Colleges students split into two groups. One group listened to “popular” favorable music from Grease!!! Another group listened to less favourable classical Indian music While listening, students viewed slide showing beige or blue Afterwards, students allowed to select pen Grease Group: 79% chose pen of same color Indian Group: 70% chose pen of different color from one they had seen on slide 8