The Effect of an Executive Functioning Training Program on Working Memory Capacity and Intrusive Thoughts.

Recurrent intrusive thoughts are apparent across numerous clinical disorders, including depression (i.e., rumination) and anxiety disorders (e.g., worry, obsessions; Brewin et al. 2010). Theoretical accounts of intrusive thoughts suggest that individual differences in executive functioning, specifically poor inhibitory control, may account for the persistence of these thoughts in some individuals (e.g., Anderson and Levy 2009). The present study examined the causal effect of inhibitory control on intrusive thoughts by experimentally manipulating inhibition requirements in a working memory capacity (WMC) task and evaluating the effect of this training on intrusive thoughts during a thought suppression task. Unselected undergraduate participants were randomly assigned to repeatedly practice a task requiring either high inhibitory control (training condition) or low inhibitory control (control condition). Results indicated that individuals in the training condition demonstrated significantly greater WMC performance improvements from pre to post assessment relative to the control group. Moreover, individuals in the training group experienced fewer intrusions during a thought suppression task. These results provide support for theoretical accounts positing a relationship between inhibitory control and intrusive thoughts. Moreover, improving inhibitory control through computerized training programs may have clinical utility in disorders characterized by recurrent intrusive thoughts (e.g., depression, PTSD).