Momentary dynamics of inner speech varieties, auditory verbal hallucinations, and affect in schizophrenia spectrum disorders: an experience sampling study.

People with schizophrenia who hear voices experience inner speech—the silent, internal monologue—more frequently and with a different character than healthy individuals. Using repeated daily surveys on electronic devices, researchers found that voice-hearers reported more moments of inner speech and higher intensity of evaluative, other people's voices, condensed, and positive inner speech, though not dialogic inner speech. When voice-hearers experienced more intense dialogic, evaluative, other people's, or condensed inner speech, they also reported more severe auditory verbal hallucinations. Negative emotions strengthened the link between evaluative inner speech and hallucination severity. The findings suggest inner speech contributes to voice-hearing and that emotional state may be a target for therapy.

Study at a glance

Abstract

Auditory verbal hallucinations (AVH) in schizophrenia spectrum disorders (SSDs) may arise from misattributed inner speech. However, it is unclear if inner speech frequency and phenomenology differ in schizophrenia-spectrum voice-hearers compared with healthy individuals, and how different inner speech varieties relate to AVH and affect. Using experience sampling methodology (ESM), this study examined the moment-to-moment dynamics between inner speech varieties, AVH, and affect. Participants completed 6 days of ESM on an electronic device, responding to 10 daily prompts on inner speech varieties (i.e. dialogic, evaluative, other people, condensed, and positive), AVH, and affect. Responses from 32 individuals with SSDs with current AVH ('SSD') and 34 healthy controls ('HC') were analyzed using linear mixed modeling. SSD reported significantly more inner speech moments and higher momentary intensity of evaluative, other people, condensed, and positive inner speech compared with HC, but not for dialogic inner speech. Within SSD, higher momentary intensities of dialogic, evaluative, other people, and condensed inner speech were associated with higher AVH levels. Momentary negative affect (NA) moderated the association between evaluative inner speech and AVH, with a stronger association at higher NA levels. SSDs with current AVH experience more frequent inner speech and exhibit a distinct phenomenological profile compared with healthy individuals. Several inner speech varieties are associated with AVH severity momentarily, supporting the hypothesis that inner speech contributes to AVH at the phenomenological level. This study highlights the emotional state as an important moderator of the inner speech-AVH relationship and as a potential therapeutic target.