The effectiveness of individual versus group induction of depressed mood

How long do mood induction procedure (MIP) primes really last? Implications for cognitive vulnerability research

BACKGROUND

Mood Induction Procedures (MIPs) are used widely in research on cognitive vulnerability to depression. Although empirical evidence supports certain MIPs as effective, little research has evaluated whether MIP-induced sad moods are sufficiently persistent. This study aimed to determine (1) how long an MIP-induced mood lasts according to commonly used operational definitions and (2) whether these findings vary according to the type of MIP used.

METHODS

Four-hundred-and-one undergraduate students were randomly assigned to one of three commonly used sad MIPs (music, memory, music+memory) or to one of three matched neutral MIPs. Mood was repeatedly measured immediately prior to and following the MIP.

RESULTS

Results did not support the widely held belief that commonly used MIPs induce a sufficient and persistent sad mood. The memory-related MIPs induced the most persistent sad mood. Based on the majority of operational definitions, however, induced mood effects did not last longer than 4 min, regardless of MIP type.

LIMITATIONS

Future studies should examine additional factors that may have affected the trajectories observed in the current study (e.g., task completed in between mood measurements) and in vulnerable (e.g., past-depressed) populations.

CONCLUSIONS

This study constitutes an important first step in validating the use of MIPs in cognitive vulnerability research and provides researchers with important information on future study designs. More important, the study raises doubt about the validity of various conclusions drawn from some MIP studies and calls into question the theoretical conceptualizations of depression that are based on potentially biased results and a possibly incomplete literature.

Online validation of combined mood induction procedures

Film clips, music, and self-referential statements (termed Velten, after their originator) have been successfully used to temporarily induce sadness and happiness. However, there is little research on the effectiveness of these procedures combined, particularly in internet-based settings, and whether Velten statements contribute to alter mood beyond the effect of simple instructions to close one's eyes and enter the targeted mood. In Study 1 (N = 106) we examined the effectiveness 80 Velten statements (positive, negative, neutral-self, neutral-facts) to create brief and effective sets that might be used in future research. In Study 2 (N = 445) we examined the effect size of 8-min combined mood induction procedures, which presented video clips in the first half and music excerpts with Velten statements or closed eyes instructions in the second half. Participants answered questionnaires on social desirability, joviality, and sadness before being randomly assigned to 1 of 7 groups varying in Valence (positive, negative, neutral) and Velten (closed eyes control, self-referential Velten, and, in the case of neutral condition, factual statements). Subsequently, participants completed the joviality and sadness scales a second time. Compared to the neutral conditions, the positive mood inductions increased joviality (Hedges G = 1.35, 95% CI [1.07, 1.63]), whereas the negative mood inductions increased sadness (Hedges G = 1.28, 95% CI [1.01, 1.55]). We did not observe any significant difference between Velten and closed eyes instructions in inducing joviality or sadness, nor did we observe any significant difference between neutral Velten statements referring to self and facts. Although social desirability bias was associated with reports of greater joviality and lower sadness, it could not account for the effects of the positive and negative mood induction procedures. We conclude that these combined mood induction procedures can be used in online research to study happy and sad mood.