1. Nic Hooper

2. What is thought suppression ? According to Daniel Wegner ‘attempting to banish ones unwanted thoughts’ In everyday terms It is the attempted removal of unwanted thoughts from the mind. A natural reaction Rachman and Da Silva (1994) 80% of people will attempt to suppress an unwanted thought

3. History of Thought Suppression ‘The topic of controlling unwanted thoughts has been of interest to psychologists for more than one century’ (Erdelyi, 1993) However ‘there is good reason to argue that research was invigorated by the thought suppression paradigm which originated from 1987’ (Rassin, 2006) The thought suppression paradigm found that when asked to suppress a simple thought, participants were unable to do so

4. Why is thought suppression important? According to Eric Rassin ‘the human incapacity to wish away unwanted thoughts’ This incapacity often causes ‘obsession’ with the thought It has subsequent links with every day problems and psychological disorders

5. Why is thought suppression important?(2) Smoking cessation (Toll, Sobell, Sobell & Wagner, 2000) Worrying (Mathews & Milroy, 1993) Stress (Roehrich & Goldman, 1995) Sleep impairment (Ree et al, 2004 ) ASD (Harvey & Bryant, 1998), OCD (Freeston & Ladouceur, 1997), GAD (Beckner et al 1988 ), PTSD (Foa, Steketee & Rothbaum, 1989; Ehlers & Steil, 1995), Specific Phobias (Thorpe & Salkovskis, 1997) Depression (Wegner, 1994)

6. Why is thought suppression difficult? A few theories have been offered Psychoanalytic theory (Freud, 1915) Theory of psychological reactance (Brehm, 1966) Self perception Theory (Bem, 1972) Unfortunately these theories have fallen short both in terms of theory and research

7. The Environmental Cueing Hypothesis (Wegner,1994) 1. Distraction 2. Distraction fails because of a two process theory 3. Distraction serves to remind us of the unwanted thought 4. Soon every distracter becomes associated with the unwanted thought 5. Meaning that everything in our environment reminds us of the unwanted thought

8. Evidence for the Environmental Cueing Hypothesis Wegner, Schneider, Carter and White (1987) Wegner, Scheider, Knutson and McMahon (1991) Muris, Merkelback and De Jong (1993) All three studies give evidence that the reason participants cannot suppress their thoughts is because the distracters they use eventually remind them of their unwanted thought

9. Evidence for the Environmental Cueing Hypothesis (2) But there are problems; The Environmental Cueing Hypothesis leaves a void in understanding functionally the underlying behavioural processes, essentially it provides simply a mechanistic and metaphorical account. One behavioural phenomenon that may provide a more functional approach to thought suppression is Stimulus Equivalence.

10. Stimulus Equivalence The concept was first introduced by Sidman (1971) Suggests that people learn by the way they relate stimuli in their environment It is suggested that this is possible via both directly trained and derived learning The concept of derived learning might help to explain the futility associated with thought suppression i.e. It helps to account for the generalisation of suppression attempts.

11. Taught Untaught Symmetry Transitivity Combination of symmetry & transitivity Reflexivity

12. Behavioural explanation of Thought Suppression People suppress (avoid) unwanted thoughts via distraction The unwanted thought/ feeling and the distracter become related So that next time you come across the distracter it is likely to remind of you of the unwanted thought Additionally the unwanted thought, via derived learning, could become related to an infinite number of untrained stimuli which also serve to cue to unwanted thought.

13. Taught Untaught

14. The Present Study Aim To find the reason behind unsuccessful thought suppression Hypothesis People will not only avoid the suppressed word but also words that are trained as related to the suppressed word; they do this because those words serve to remind them of the to be suppressed thought.

15. Methodology 1. Screening measures 2. Equivalence training and testing 3. Five minute suppression phase 4 Induction of cognitive load 5 Avoidance program

16. Methodology Equivalence: Trains people to relate certain words to each other 3x3 equivalence matrix Enables derived relation to be learned Enables us to control their learning history in this context.

17. Methodology Avoidance Paradigm Novel way to study generalization People are asked to suppress unwanted thought Whilst looking at words appearing on a computer screen They are told that they are in control of the program so that if they would like to remove a word then they could do so The idea is to see if they simply removed the unwanted word, or also the words trained as related to it in the equivalence training!

18. Control group It could be argued that participants removed related words as an artefact of equivalence and not as an artefact of suppression To account for this a control group did not receive suppression instructions but were instead asked to remove the word ‘bear’ from the screen If they too removed the related words then this would nullify the results of the experimental group.

19. Analysis 2x3 Mixed ANOVA 2 (condition; suppress or instruct) x 3 (word type; target, related and non related) Found a significant main effect f(2,56) = 294.49, p<0.001 Additional T-Tests showed a significant difference between target related and non related t (14) = -6.73, p<0.0001

20. Results

21. Discussion Words trained as related to the target word were removed from the screen i.e. there was a transfer of suppression functions across equivalence class members This displays how our previous relational learning can promote the counterproductive nature associated with unsuccessful suppression This effect did not occur in the control group

22. Implications This knowledge of why thought suppression doesn't work has real life implications; According to RFT (a theory of learning and language that utilizes derived learning) learning is additive so that it is impossible to undo the relations that have been learned Suggesting that thought suppression will never work because we’ll never be able to change the vast relational networks we have. There’s no way to stop the effects but there might be a way to treat it Acceptance and Commitment Therapy

23. Future Research Research ACT Integrate aspects of ACT into laboratory studies To find out if Acceptance, instead of suppression, is a better technique for dealing with unwanted thought and feelings

24. Thank you