UC Irvine

The effect of positive and negative mood on different cognitive processes remains largely unknown due to mixed findings. One reason for this is that the methods used in mood induction procedures are widely varied. This study therefore aimed to elucidate the effect of positive and negative mood on two cognitive processes used extensively in daily life: working memory capacity measured using the running memory span, and prepotent inhibition measured using the Flanker task. This study also utilized the three parameters (mu, sigma and tau) of ex-Gaussian distribution to analyze the reaction time data. Participants (N = 306) were predominantly young adults recruited from an undergraduate sample (M = 21.1 years old, SD = 4.2). They were randomly assigned to a positive, negative, or neutral mood group and underwent a mood induction by a watching 3-minute-long video clip. They then performed the running memory span or the Flanker task in a counter-balanced order. Analysis of variance indicate that there was no effect of condition on working memory capacity nor prepotent inhibition. Exploratory analyses indicated that positive mood showed a non-significant tendency to be associated with greater difficulty in prepotent response inhibition, whereas negative mood showed a non-significant tendency to be associated with slower responses (larger tau) in stimulus incompatible trials. These mixed findings suggest that positive and negative mood might influence response inhibition differentially and that there needs to be further experimentation to clarify the differential effect of positive and negative mood on different cognitive processes.