title: Distribution of Response Time, Cortical, and Cardiac Correlates during Emotional Interference in Persons with Subclinical Psychotic Symptoms.
abstract: A psychosis phenotype can be observed below the threshold of clinical detection. The study aimed to investigate whether subclinical psychotic symptoms are associated with deficits in controlling emotional interference, and whether cortical brain and cardiac correlates of these deficits can be detected using functional near-infrared spectroscopy (fNIRS). A data set derived from a community sample was obtained from the Zurich Program for Sustainable Development of Mental Health Services. 174 subjects (mean age 29.67 ± 6.41, 91 females) were assigned to four groups ranging from low to high levels of subclinical psychotic symptoms (derived from the Symptom Checklist-90-R). Emotional interference was assessed using the emotional Stroop task comprising neutral, positive, and negative conditions. Statistical distributional methods based on delta plots [behavioral response time (RT) data] and quantile analysis (fNIRS data) were applied to evaluate the emotional interference effects. Results showed that both interference effects and disorder-specific (i.e., group-specific) effects could be detected, based on behavioral RTs, cortical hemodynamic signals (brain correlates), and heart rate variability (cardiac correlates). Subjects with high compared to low subclinical psychotic symptoms revealed significantly reduced amplitudes in dorsolateral prefrontal cortices (interference effect, p < 0.001) and middle temporal gyrus (disorder-specific group effect, p < 0.001), supported by behavioral and heart rate results. The present findings indicate that distributional analyses methods can support the detection of emotional interference effects in the emotional Stroop. The results suggested that subjects with high subclinical psychosis exhibit enhanced emotional interference effects. Based on these observations, subclinical psychosis may therefore prove to represent a valid extension of the clinical psychosis phenotype.
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry Zurich Zurich, Switzerland.
authors.forename: Lisa K B
authors.initials: LK
authors.lastname: Holper
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry ZurichZurich, Switzerland; The Zurich Program for Sustainable Development of Mental Health Services, University Hospital of Psychiatry ZurichZurich, Switzerland.
authors.forename: Alekandra
authors.initials: A
authors.lastname: Aleksandrowicz
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry ZurichZurich, Switzerland; The Zurich Program for Sustainable Development of Mental Health Services, University Hospital of Psychiatry ZurichZurich, Switzerland.
authors.forename: Mario
authors.initials: M
authors.lastname: Müller
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry Zurich Zurich, Switzerland.
authors.forename: Vladeta
authors.initials: V
authors.lastname: Ajdacic-Gross
authors.affiliation: The Zurich Program for Sustainable Development of Mental Health Services, University Hospital of Psychiatry ZurichZurich, Switzerland; Translational Neuromodeling Unit, Institute for Biomedical Engineering, University of Zurich and ETH ZurichSwitzerland.
authors.forename: Helene
authors.initials: H
authors.lastname: Haker
authors.affiliation: Department of Psychiatry and Psychotherapy, University of TübingenTübingen, Germany; LEAD Graduate School, University of TübingenTübingen, Germany.
authors.forename: Andreas J
authors.initials: AJ
authors.lastname: Fallgatter
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry ZurichZurich, Switzerland; The Zurich Program for Sustainable Development of Mental Health Services, University Hospital of Psychiatry ZurichZurich, Switzerland.
authors.forename: Florence
authors.initials: F
authors.lastname: Hagenmuller
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry ZurichZurich, Switzerland; The Zurich Program for Sustainable Development of Mental Health Services, University Hospital of Psychiatry ZurichZurich, Switzerland.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Kawohl
authors.affiliation: Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry ZurichZurich, Switzerland; The Zurich Program for Sustainable Development of Mental Health Services, University Hospital of Psychiatry ZurichZurich, Switzerland; Laboratory of Neuroscience (LIM27), Institute of Psychiatry, University of São PauloSão Paulo, Brazil; Department of Psychiatry and Psychotherapy, Charité University MedicineBerlin, Germany.
authors.forename: Wulf
authors.initials: W
authors.lastname: Rössler
keywords: delta plot; emotional Stroop; epidemiology; fNIRS; paranoid ideation; psychoticism; quantile analysis