Is schizotypy associated with babble-induced speech illusions and negative valence?

Abstract

The tendency to perceive longer speech illusions when listening to multispeaker babble is associated with an increased risk of schizophrenia in prodromal individuals. In addition, the detection of speech illusions in white noise has been strongly associated with higher positive schizotypy in psychosis-free controls. The purpose of the current study was to determine whether these speech illusion tendencies are observed in self-reported schizotypy when using the babble task. A secondary aim was to investigate the relationship between the affective valence of speech illusions and schizotypy. Undergraduates (n = 402) completed the schizotypal personality questionnaire and the psychobabble speech perception task. As expected, participants with higher positive schizotypy produced longer and more speech illusions in response to the psychobabble stimulus. These findings provide further evidence that speech illusions in schizotypy may serve as an early marker of risk for schizophrenia. However, negative schizotypy was associated with reporting of fewer speech illusions, perhaps indicating that the psychobabble task is sensitive to the positive symptom domain of schizotypy only. Moreover, higher disorganised schizotypy was associated with negative but not positive speech illusions, consistent with reports that verbal hallucinations in schizophrenia commonly have a negative valence. The experience of speech illusions when listening to multispeaker babble may have some utility as an objective measure of risk for schizophrenia, complementing self-report data. Further investigation is required to ascertain whether psychobabble speech illusions in schizotypy are predictive of subsequent illness.