Abstract
Background and Objectives: The general positivity training, a Cognitive Bias Modification procedure modifying individuals' approach-avoidance tendencies to positively and negatively valenced pictures by means of a joystick task, has been proven effective in attenuating stress reactivity in dysphoric students. The present study explored which training component (pull positive pictures, push negative pictures, or both) is the active one in changing action tendencies and stress responses. Methods: Two-hundred-and-thirteen students completed one of four approach-avoidance trainings before being exposed to a stressful speech-task: The general positivity training (pull positive and push negative pictures), a training to approach positive pictures and avoid empty pictures (ApP), a training to avoid negative pictures and approach empty pictures (AvN), or a sham-training. Results The pattern of results suggests that the groups trained to avoid negative pictures showed a stronger increase in positive approach-avoidance tendencies than the other two groups. However, only the positivity training induced significant within-group changes in positive bias. The groups further did not differ in self-report or cardiovascular measures of anxiety in response to the stress-task. Instead, the training affected mood directly: Exposure to negative pictures during the training increased state anxiety. Limitations: Generalizability of the findings is limited by using an unselected student sample. Also, the use of empty pictures as neutral stimuli in the ApP and AvN could have weakened training effects in these groups. Conclusions: Although our results hint at the importance of avoiding negative pictures for modifying an approach-avoidance bias, only the positivity training with both components may effectively induce a positive bias. Remarkably, we failed to replicate and extend previously reported effects of the training on stress-responses. Hence, it remains questionable whether the changes in bias reflect changes in underlying cognitive processing tendencies or task-specific learning effects.
