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Reproducibility of Negative Mood Induction: a Self-Referent Plus Musical Mood Induction Procedure and a Controllable/Uncontrollable Stress Paradigm

Mood induction procedures (MIPs) have been used extensively as a means of inducing a variety of mood states in laboratory settings. Recently, MIPs have been employed in a repeated measures design in combination with such techniques as functional imaging and psychopharmacological investigations. This study attempted to assess the repeatability of two paradigms designed to induce a depressed/negative affect, a self-referent plus musical MIP and a controllable/uncontrollable stress paradigm, to assess the viability of using such procedures in a repeated design. Healthy volunteers were enrolled in to one of two studies. Study 1 administered a self-referent plus musical MIP on three separate occasions: neutral and depressive mood induction (MI) in a balanced order, followed by a further depressive MI. In study 2, volunteers were subjected to sessions of controllable and uncontrollable noise stress in a balanced order on two different occasions. Subjective ratings of mood were obtained prior to and following the interventions. Depressive MI successfully increased ratings of negative affect, although this effect tended to be greater on the first occasion than on the second. Correlation between mood change on the first and second occasions were low, both for the MIP and stress paradigm. As such, caution should be exercised in using these procedures in a repeated measures design. However, the results may vary depending on the type of MIP employed.