Submission 327
Source Monitoring Along the Continuum of Psychosis: Insights from Schizotypy
SymposiumTalk-05
Presented by: Isabel Porstein
Theory and empirical findings link reality monitoring impairments to positive symptoms in schizophrenia but confounds limit conclusions. Studies examining reality monitoring in subclinical schizotypy have produced contradictory results. This may be due to paradigms not assessing all types of source monitoring, overlooking schizotypy’s multidimensionality, and failing to disentangle memory from guessing. Addressing this, we developed a four-source memory paradigm assessing external source monitoring, internal source monitoring, and reality monitoring. Participants view everyday objects presented with two external sources (female or a male voice speaking) and two internal sources (imagining themselves or another voice saying the object name). We extended the Two High Threshold Model of Source Monitoring (2HTSM; Bayen et al., 1996) to four sources with confirmed identifiability. Multinomial modelling separates source memory from guessing, providing accurate estimates. A pilot study with N = 40 participants confirmed the fit of empirical data with the model. We are currently pre-screening N = 400 participants with the Multidimensional Schizotypy Scale (Kwapil et al., 2018) assessing the positive, negative, and disorganized schizotypy dimensions separately. As of now, n = 352 have been screened of which n = 106 score high on at least one dimension. The scale shows good initial reliability. Later, a sample of N = 150 participants, including n = 50 scoring > 1.5 SD above mean on any dimension, will be invited to take part in the piloted experiment. The three schizotypy dimensions will be entered as simultaneous predictors to estimate their unique influence on source memory.