Cognitive Neurocomputational Task Reliability & Clinical Applications Consortium (CNTRACS): Study 1

In Study 1, investigators will test the ability of each of the seven paradigms to differentiate between schizophrenia (SZ)/schizoaffective disorder (SZA) and matched healthy control subjects (HC) and to predict individual differences in clinical measures of hallucinations and delusions (as well as measures of function). Investigators will also directly compare the tasks in terms of predictive ability and psychometric properties and determine whether the tasks share variance or explain unique variance. This will include determining whether hallucinations and delusions are best explained by separate underlying processes or by a single process. Investigators will also test whether the model-based parameters from these studies are more precise and sensitive than standard behavioral methods for assessing deficits across psychotic disorders and for predicting hallucinations and delusions (Aim 1). Investigators will also validate key model-based parameters against well-characterized neurophysiological measures using electroencephalogram (EEG) (Aim 4). The data from Study 1 will also be used to optimize (e.g., length, floor, and ceiling effects) tasks for Study 2. To generate a sample with sufficient variation in hallucinations and delusions, investigators will recruit the following groups that balance feasibility with clinical relevance: A) healthy controls (HC) [HC, N=125]; B) schizophrenia and schizoaffective disorder [SZ/SZA, N=200]). For Study 1, investigators will ensure that 40 patients are unmedicated. Investigators anticipate a ~20% screen fail/drop-out rate based on our prior Cognitive Neuroscience Test Reliability and Clinical Applications for Schizophrenia Consortium (CNTRACS) studies. Thus, investigators will run an additional 40 SZ/SZA and 15 HC. All sites have experience recruiting patients in each of these groups as indicated by our past successful studies, and the fact that investigators have been able to recruit patients with significant hallucinations and delusions in all groups. Investigators will also validate key model-based parameters against well-characterized neurophysiological measures using electroencephalogram (EEG) (Aim 4). The data from Study 1 will also be used to optimize (e.g., length, floor, and ceiling effects) tasks for Study 2. To generate a sample with sufficient variation in hallucinations and delusions, investigators will recruit the following groups that balance feasibility with clinical relevance: A) healthy controls (HC) [HC, N=125]; B) schizophrenia and schizoaffective disorder [SZ/SZA, N=200]). For Study 1, investigators will ensure that 40 patients are unmedicated. Investigators anticipate a ~20% screen fail/drop-out rate based on our prior Cognitive Neuroscience Test Reliability and Clinical Applications for Schizophrenia Consortium (CNTRACS) studies. Thus, investigators will run an additional 40 SZ/SZA and 15 HC. All sites have experience recruiting patients in each of these groups as indicated by our past successful studies, and the fact that investigators have been able to recruit patients with significant hallucinations and delusions in all groups.

Each participant will complete 4 sessions (~3 hours each) within 3 weeks, as in our prior studies. The first session includes clinical, self-report, proxy function, and community function assessments. Sessions 2-4 are for task and electroencephalogram (EEG) measurements. Each participant will complete 7 tasks across these sessions, while EEG is recorded. Task order will be counterbalanced across sessions. Clinical Assessment and Self-Report: A trained assessor will diagnose participants using the Structured Clinical Interview (SCID-5) for Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) Text Revision 59 (TR59). Clinicians will rate hallucination and delusion symptom severity with the Chicago Hallucinations Assessment Tool (CHAT) and the Brief Psychiatric Rating Scale (BPRS). Investigators will use the Psychotic Symptom Rating Scales (PSYRATS) to evaluate the degree of preoccupation, conviction, distress, and life disruption associated with hallucinations and delusions elicited on the BPRS and CHAT. To address specificity, investigators will administer the Clinical Assessment Interview for Negative Symptoms (CAINS). For self-report, investigators will use the Beliefs about Voices Scale, which assesses attributions about the origin and power of voices, and the Yale Control Over Perceptual Experiences (COPE) scale, which evaluates the extent to which people feel they can exert control over their voices. Investigators also will use the Peters Delusion Inventory to assess the extent of delusional thinking, supplemented by the Green Paranoia Scale to provide additional coverage of persecutory beliefs. To assess specificity, investigators will use the Patient Health Questionnaire (PHQ-9) to assess depression, the Generalized Anxiety Disorder Scale (GAD-7) to assess anxiety, and the Motivation and Pleasure Scale-Self-Report (MAP-SR) to assess anhedonia and motivation. Investigators will conduct a principal components analysis (PCA) on measures of the same construct (e.g., delusions) and perform primary analyses using the first principal component, followed by secondary analyses of specific measures False Discovery Rate (FDR) correction. Community Function: Patients will complete the Specific Levels of Functioning (SLOF) scale, a validated scale of work and community function. National Institute of Mental Health (NIMH) Common Data Elements: Investigators will acquire the additional NIMH Tier 1 Common Data elements (e.g., World Health Organization Disability Assessment Schedule 2 (WHODAS 2.0) & DSM-5 Symptom Measure). General Cognitive Ability. Investigators will include standard general cognitive measures to assess the specificity of effects beyond general cognitive impairment. Specifically, investigators will include validated online measures from TestMyBrain (https://www.testmybrain.org/using-tmb/research.html; Digit Symbol Coding, Vocabulary, and Matrix Reasoning), as in our prior work in both clinical and healthy populations. Electroencephalogram (EEG) Procedures: During the above tasks, 64-channel EEG will be recorded from Direct Current (DC)-130 Hertz (Hz) using a 500 Hz sampling rate. Offline data preprocessing will be conducted using Matlab toolboxes EEGLAB and ERPLAB, including segmenting, baseline correction, Independent Component Analysis (ICA)-based artifact correction, artifact rejection, and filtering.