Hallucination proneness alters sensory feedback processing in self-voice production

Abstract

BackgroundSensory suppression occurs when hearing ones self-generated voice, as opposed to passively listening to ones own voice. Quality changes of sensory feedback to the self-generated voice can increase attentional control. These changes affect the self-other voice distinction and might lead to hearing non-existent voices in the absence of an external source (i.e., auditory verbal hallucinations (AVH)). However, it is unclear how changes in sensory feedback processing and attention allocation interact and how this interaction might relate to hallucination proneness (HP). Study DesignParticipants varying in HP self-generated and passively listened to their voice that varied in emotional quality and certainty of recognition -- 100% neutral, 60-40% neutral-angry, 50-50% neutral-angry, 40-60% neutral-angry, 100% angry, during EEG recordings. Study ResultsThe N1 auditory evoked potential was more suppressed for the self-generated than externally generated voices. Increased HP was associated with (i) an increased N1 response to the self-compared to externally generated voices, (ii) a reduced N1 response for angry compared to neutral voices, and (iii) a reduced N2 response to unexpected voice quality in sensory feedback (60-40% neutral-angry) compared to neutral voices. ConclusionsThe current study highlights an association between increased HP and systematic changes of the emotional quality and certainty in sensory feedback processing (N1) and attentional control (N2) in self-voice production in a non-clinical population. Considering that voice hearers also display these changes, these findings support the continuum hypothesis. However, additional research is needed to validate this conclusion.