Longenecker, Julia2021-10-132021-10-132019-08https://hdl.handle.net/11299/224942University of Minnesota Ph.D. dissertation. August 2019. Major: Psychology. Advisors: Robert Krueger, Scott Sponheim. 1 computer file (PDF); vii, 111 pages.‘Apophenia’, or the tendency to find patterns in unrelated perceptions, may link normative and pathological sensory experiences. Apophenia has been well-characterized by personality assessment, but has limited behavioral and functional correlates, particularly in clinical populations. Object detection is predicted by apophenia traits in normative populations. Behavioral and neurobiological object detection abnormalities are pervasive in schizophrenia, yet have not been investigated with respect to apophenia. The current set of studies explore multiple levels of perceptual disturbances in normative and psychiatric samples. Study 1 investigated personality and object detection in an undergraduate sample (N=191). The object detection task, Fragmented Ambiguous Object Task (FAOT), controls for low-level visual properties while presenting disjointed object representations of varying difficulty. Personality was comprehensively assessed with the Big Five Aspect Scale (BFAS), Multidimensional Personality Questionnaire (MPQ), and Personality Inventory for DSM-5 (PID-5). Study 2 sought to replicate Study 1 in a clinical population and extend the investigation to EEG in outpatients with psychotic disorders, first-degree biological relatives, and psychiatrically unaffected individuals. Event-related potentials (ERPs) – P1, N1, closure negativity (NCL), and anterior components – were recorded with a 128 channel EEG system. Participants underwent comprehensive clinical assessment, and completed MPQ Absorption and PID-5. In Study 1, object detection was positively associated with BFAS Openness, MPQ Absorption and PID-5 Psychoticism. Additionally, BFAS Conscientiousness and PID-5 Disinhibition predicted object detection. Study 2 did not replicate the association between FAOT and personality, or show an object detection deficit in psychotic disorders. The hypotheses regarding ERPs were largely unsupported. Instead, findings suggested group differences in semantic processing during FAOT, and an anterior component associated with frequent object detection. Personality measures of apophenia were consistently related to experimentally manipulated visual perception in the general population but not persons with psychotic disorders. The present research attempted to unify observations in personality psychology, clinical research, and vision neuroscience of object detection. Deviations in perceptual functions that support the detection of ambiguous visual stimuli reflect normative expressions of trait-level apophenia. However, further investigation is necessary to connect apophenia to psychotic phenomenology in the context of mental illness.enOpennesspsychologyschizophreniavisual perceptionThesis or Dissertation