Inner experience differs in rumination and distraction without a change in electromyographical correlates of inner speech

Abstract

Ruminative thought is a style of thinking which involves repetitively focusing upon one’s own negative mood, its causes and its consequences. The negative effects of rumination are well-documented, but comparatively little is known about how rumination is experienced. The evaluative nature of rumination suggests that it could involve more inner speech than non-ruminative states. The present study ( N = 31) combined facial electromyography and self-report questionnaires to determine the type of inner experience that occurs in rumination. The results showed that induced rumination involved similar levels of muscle activity related to inner speech as periods of induced distraction. However, experience sampling and questionnaire responses showed that rumination involved more verbal thought, and also involved more evaluative and dialogic inner speech than distraction. These findings contribute to the understanding of inner speech as a flexible phenomenon and confirms the importance of employing multiple methods to investigate inner speech. Future research should clarify the link between inner speech in rumination and its negative effects on wellbeing.

Re-analysing the data from Moffatt et al. (2020): What can we learn from an under-powered absence of difference?

“…As typical in studies manipulating induced rumination, Moffatt et al (2020) designed a two-step protocol. First, they aimed to induce a negative mood by asking participants to solve unsolvable or excessively difficult anagram and subtraction tasks.…”

“…This figure reveals that the most probable value for this difference was = 0.228 (95% CrI [0.098, 0.357]) for the FRO muscle, = 0.081 (95% CrI [-0.155, 0.324]) for the OOI muscle, and = 0.047 (95% CrI [-0.167, 0.27]) for the OOS muscle. Moreover, comparing the posterior distribution to = 0 reveals that there is a probability of 0.753 that the average peak EMG amplitude recorded over the OOI is higher in the rumination condition than in the distraction condition (given the model, the priors, and the data from Moffatt et al, 2020).…”

“…Anticipating the legitimate critiques on the power of their study, Moffatt et al (2020) report the results of a power analysis using the effect size reported in Nalborczyk et al…”

“…Although these points were not addressed by Moffatt et al (2020), their experimental design nevertheless had the potential to inform our understanding of the involvement of the speech motor system in different varieties of inner speech as well as to clarify the relation between the peripheral correlates of inner speech and (self-reported) subjective experience.…”

“…The main conclusion from Moffatt et al (2020) is that inner experience between induced rumination and distraction differs "without a change in electromyographic correlates of inner speech" (p.1). In other words, they suggest that the subjective experience of inner speech is unrelated (or loosely related) to the electromyographic correlates of inner speech, which are thought to be represented mostly by the EMG amplitude recorded over the orbicularis oris inferior and orbicularis oris superior muscles.…”