Abstract
Patients with psychosis experience deficits in multisensory integration (MSI), or the communication between different sensory modalities, such as sound and sight. One way to assess multisensory integrations is by utilizing voice-pitch tasks in which participants hear the pitch of their own voice artificially altered by a computer. When healthy individuals hear this computerized pitch-shift, they respond behaviorally by changing their own pitch. This is a reflexive attempt to “correct” a perceived error, demonstrating communication between the sensory system and the motor system. While voice-pitch tasks have been used to assess MSI in patients with Parkinson’s disease (another population with emergent MSI abnormalities), it is unclear what responses on voice-pitch tasks look like in psychosis populations. One way to address this unknown question is to assess voice-pitch task performance in individuals with nonclinical psychosis (NCP) who are otherwise healthy but experience occasional psychotic-like experiences (PLEs). In the present study, a total of 36 participants (11 NCP and 25 controls) were asked to complete a voice-pitch task in which they held a constant and steady “ahh” sound. While vocalizing, they heard the pitch of their voice artificially shifted by a computer, and the task determined if they consequently shifted pitch in response to the stimuli. I then compared the groups on magnitude and latency of the participant vocal responses, and predicted that the NCP group would exhibit abnormalities in their performance, demonstrated by greater magnitudes and longer latencies. Although results from the study were not statistically significant, the effect size and pattern of trends both suggest that with increased power, the NCP group may show deficits in sensorimotor integration, reflected by abnormal performance on the voice-pitch task when compared to controls. Studying integration patterns among at-risk samples and psychosis populations may identify a potential vulnerability marker relevant for understanding the pathogenesis of psychosis.