Exploring the interaction between Schizotypy personality and working memory on speech illusions

This study used the schizotypy personality as a proxy for schizophrenia to understand the mechanisms underlying speech illusions ‚Äö- the perception of meaningful speech in ambiguous auditory signals - in a normative population. To assess the interaction between working memory and schizotypy personality on speech illusions, Hoffmann's (1999) Multi-speaker babble task was used. We hypothesized that individuals high on the schizotypy spectrum and with a lower working memory would score higher on the babble task, compared to high schizotypic individuals with higher working memory. Sixty-two participants completed the babble task, measures of schizotypy personality, and measures of working memory. Moderation analyses were conducted to assess the interaction between the level of schizotypy and the different aspects of working memory on the babble task. Contrary to the hypothesis, it was found that high schizotypic individuals who had a higher auditory/visual verbal working memory were able to detect more words in the babble task. The interaction between working memory and liabilities to speech illusions on the babble task in this normative sample differed from those found in prior research in clinical/subclinical populations. This suggests that the mechanisms underlying speech illusions experienced by the general population might be different from those in clinical population.