Classical Conditioning in Medical and Mental Applications

1. Classical Conditioning – Ch. 5 September 23, 2005 Class #14

2. Medical/Mental Applications • Classically conditioned allergies??? • Immune system reactions • Treatment for pedophiles

3. Russell et al. (1984) • Participants • 8 adult male guinea pigs • Procedure • Paired certain smells with allergy-producing protein • Group 1: sulfur-smell • Group 2: fish-smell

4. Russell et al. (1984) • UCS ------------------------------------------- UCR (allergy-producing protein) (allergic reaction) • NS -------------------------------------------- NO RESPONSE (fish) (no reaction) • NS + UCS ----------------------------------- UCR (fish) (protein) (allergic reaction) * This is repeated several times… •  CS --------------------------------------------- CR (fish) (allergic reaction)

5. Immune System studies.. • Ader and Cohen (1975) • Rats drank a saccharin solution immediately before the injection of cyclophosphamide, an immunosuppressive drug that also has aversive gastrointestinal side effects • Following this pairing, rats avoided drinking the saccharin solution – another taste aversion study

6. O'Reilly and Exon (1986) • These researchers paired a saccharin taste (NS) with the immunosuppressing cyclophosphamide (UCS) • One of cyclophosphamide's natural effects is the reduction of natural killer-cell activity • Natural killer-cells are one of an organism's first defenses against the development of malignant tumors • When they find a cell that has been infected with a virus or one that has become cancerous, they engulf and destroy it • When O'Reilly and Exon presented saccharin to their rat subjects, it resulted in a conditioned taste aversion as well as a conditioned reduction in natural killer-cell cytotoxicity

7. Bovbjerg and Redd (1990) • Participants • 20 female ovarian cancer patients • Procedure • Chemotherapy given to patients in hospital setting • Patients return home within 24-48 hours after treatment • Hypothesis • Classically conditioned anticipatory nausea and vomiting (ANV) and anticipatory immune suppression (AIS)

8. Bovbjerg and Redd (1990) • UCS ------------------------------------------- UCR (chemo) (nausea/vomiting) • NS -------------------------------------------- NO RESPONSE (hospital) (no reaction) • NS + UCS ----------------------------------- UCR (hospital) (chemo) (nausea/vomiting) * This is repeated several times… •  CS --------------------------------------------- CR (hospital) (nausea/vomiting)

9. Bovbjerg and Redd (1990) • UCS ------------------------------------------- UCR (chemo) (immunosuppressive) • NS -------------------------------------------- NO RESPONSE (hospital) (no reaction) • NS + UCS ----------------------------------- UCR (hospital) (chemo) (immunosuppressive) * This is repeated several times… •  CS --------------------------------------------- CR (hospital) (immunosuppressive)

10. Results • Participants experienced both decreased immune function and increased nausea when they returned to hospital setting

11. Practical Implication • Could cancer patients decrease in immune functioning possibly be avoided?

12. Buske-Kirschbaum et al. (1994) • Healthy volunteers were provided with a (sherbet sweet/white noise), which was repeatedly paired with an injection of epinephrine (US) • After epinephrine injections (0.2 mg subcutaneously), a transient increase of natural killer (NK) cell activity (UR) could be observed • Later, the sherbet itself elicited an increase in NK cell activity

13. Treatment for Sexual Aggressors • Hall et al. (1993) • Pairing of photographic images of unclothed children with aversive stimuli • Drug-induced nausea similar to Antabus treatments for alcohol abusers • Unpleasant scents (ammonia) • Limited success

14. Placebo Effect • Might be employed to help some of these individuals