From intrusive thoughts to obsessions: The role of perceptions of responsibility, salience, and thought suppression.

Salkovskis [1985. Obsessional-compulsive problems: A cognitive-behavioural analysis. Behaviour Research and Therapy, 23, 571-583.] hypothesized that intrusive thoughts are more likely to occur if the thought is salient for the individual, triggers feelings of responsibility and if the individual attempts to suppress the thought. The relationship between these three factors (responsibility, salience, thought suppression) and frequency of intrusive thoughts as well as anxiety were examined in the present study. One hundred female college students were led to believe that a snake had escaped from the cage in which it was housed. Half of the participants were led to believe that they were responsible for the snake's escape and half were not (Responsibility/No Responsibility). Half of the participants in each Responsibility condition were instructed to suppress thoughts of snakes during a stream of consciousness exercise and half were not (Thought Suppression vs. No Thought Suppression). All participants then completed a second stream of consciousness without suppression instructions. Salience groups were determined by a median split on a measure of snake fearfulness. Participants for whom the snake was a salient stimulus and who believed that they were responsible for the snake's escape had the highest frequency of snake thoughts during the second stream of consciousness task and also experienced the highest levels of state anxiety. Findings are discussed with respect to Salkovskis' model.

The relationship between cognitive avoidance and attentional bias for snake-related thoughts.

Building on the work of Lavy and van den Hout (Lavy, E. H., & van den Hout, M. A. (1994a). Cognitive avoidance and attentional bias: Causal relationships. Cognitive Therapy and Research, 18 (2) 179-191; Lavy, E. H., & van den Hout, M. A. (1994b). Cognitive avoidance and attentional bias: Causal relationships. Behavior Therapy, 24, 645-657), the purpose of the present study was to examine a functional relationship between thought suppression and attentional bias for snake-related thoughts. It was hypothesized that thought suppression is causally involved in the emergence of attentional bias. An experiment was conducted with 71 snake-fearful and non-snake-fearful participants to investigate whether instructions for suppression were sufficient to induce an attentional bias toward snake-related words. Thirty-five participants were instructed to suppress all snake-related thoughts, while 36 participants received control instructions. Both groups then completed a 5-min stream of consciousness exercise followed by a dot-probe attention task including snake words, general emotion words, and neutral words. Results indicated that participants instructed to suppress snake-related thoughts exhibited a more pronounced attentional bias toward snake-related word pairs. The same participants did not exhibit an attentional bias toward general emotion or neutral words. Moreover, there was a significant negative correlation between snake-related thoughts and probe detection latency. Results are interpreted as providing support for a causal relationship between thought suppression and attentional bias for snake-related thoughts.