Effect of Depression on Attention via Mood Induction in a Healthy Population

This project continues research into the cognitive attention of persons with a sad mood similar to that experienced by dysthymia. The project utilizes the Dot Probe Task to evaluate attention to affective stimuli presented in the International Affective Picture Set (IAPS). Participants were psychology students recruited from La Sierra University. Participants completed a word task that intended to induce a sad or neutral mood. The Positive and Negative Affect Scale (PANAS) was used to evaluate the efficacy of the mood induction. Overall, participant’s negative PANAS scale did not differ between groups. Groups differed between administrations of the PANAS on the positive scale. Ultimately, there was no evidence suggesting the mood induction worked. Overall both groups responded more quickly to targets paired with neutral stimuli and reaction times were progressively slower as valence increased in the stimuli. Inhibition of Return (IOR) is suspected to be a problem due to longer probe presentation of 750 milliseconds. An interaction effect was found between gender and group on valence of the images. Women in the negative mood group responded faster to targets paired with positive images, men in the same group responded faster to targets paired with negative images. This effect was opposite from the control group and suggests that the IAPS was either not appropriate for the sample or women react differently to sad mood than men. Further research with a stronger mood induction and a control for IOR is suggested