Inner speech does not represent an epiphenomenon: Commentary on Verhaeghen & Mirabito (2021)

Using correlations and hierarchical regression analysis, Verhaeghen and Mirabito (2021) found that while self-awareness was associated with self-regulation, inner speech was not, suggesting that the latter does not play a causal role in either self-awareness nor self-regulation. This motivated the authors to claim that “inner speech is easiest understood as an epiphenomenon” (p. 8). In this Commentary, I suggest that the authors conceptualized and measured inner speech, self-regulation, and self-awareness in inappropriate ways. The two measures chosen to assess inner speech either do not relate to self-regulation (VISQ) or self-awareness (SVQ). Self-awareness was measured using composites of various scales assessing mindfulness (which represents a related, yet different construct) which contains multiple items not representative of a typical self-awareness process. The self-regulation measure was also produced using various subscales assessing self-preoccupation and self-compassion—two self-processes very loosely associated with the target construct. Different results would have been obtained if the authors had used established measures. Their results contradict what has been consistently reported in the literature and do not cast doubt on the recognized fact that inner speech plays a significant, and often causal, role in self-awareness and self-regulation.