The role of inner speech on the association between childhood adversity and 'hearing voices'

The psychometric properties of the Varieties of Inner Speech Questionnaire-Revised in Hebrew

Introduction

The Varieties of Inner Speech Questionnaire-Revised (VISQ-R) is a self-report questionnaire designed to measure characteristics of inner speech. In the current study, we adapted and validated a Hebrew version of VISQ-R. Our first hypothesis was that Confirmatory Factor Analysis (CFA) of the Hebrew VISQ-R would confirm the five subscales replicating the factor structure of the original questionnaire. In addition, building on previous findings that inner speech is involved in tasks that require the executive functions we examined the relationship between VISQ-R and self-reported executive functions questionnaire (BRIEF-A). We hypothesized that correlations between subscales of the Hebrew VISQ-R would reveal covariance between BRIEF-A and some but not all inner speech subscales.

Methods

406 participants completed the Hebrew VISQ-R and 280 of them also completed the BRIEF-A.

Results

As hypothesized, CFA confirmed the factor structure revealing the same 5 subscales reported in the original English version, with acceptable internal reliability. Partial support was found for the hypothesized correlations between VISQ-R and BRIEF-A, with covariance of executive functions with some subscales of inner speech (Evaluative, Other-People and Dialogic), and distinct variance with others (Condensed and Positive).

Discussion

These results indicate that the Hebrew version of the VISQ-R has good psychometric properties and that it can be used in future research. The implications concerning the contribution of inner speech for people with difficulties in executive functions are discussed.

A voice without a mouth no more: The neurobiology of language and consciousness

Most research on the neurobiology of language ignores consciousness and vice versa. Here, language, with an emphasis on inner speech, is hypothesised to generate and sustain self-awareness, i.e., higher-order consciousness. Converging evidence supporting this hypothesis is reviewed. To account for these findings, a 'HOLISTIC' model of neurobiology of language, inner speech, and consciousness is proposed. It involves a 'core' set of inner speech production regions that initiate the experience of feeling and hearing words. These take on affective qualities, deriving from activation of associated sensory, motor, and emotional representations, involving a largely unconscious dynamic 'periphery', distributed throughout the whole brain. Responding to those words forms the basis for sustained network activity, involving 'default mode' activation and prefrontal and thalamic/brainstem selection of contextually relevant responses. Evidence for the model is reviewed, supporting neuroimaging meta-analyses conducted, and comparisons with other theories of consciousness made. The HOLISTIC model constitutes a more parsimonious and complete account of the 'neural correlates of consciousness' that has implications for a mechanistic account of mental health and wellbeing.