Auditory Oddball Responses Across the Schizophrenia-Bipolar Spectrum and Their Relationship to Cognitive and Clinical Features

Objective: Neural activations during auditory oddball tasks Results: Twenty-six EEG features differentiated the may be endophenotypes for psychosis and bipolar disorder. groups; they were used in discriminant and correlational The authors investigated oddball neural deviations that dis-analyses. EEG variables from the N100, P300, and lowcriminate multiple diagnostic groups across the schizo-frequency ranges separated the groups along a diagnostic phrenia-bipolar spectrum (schizophrenia, schizoaffective continuum from healthy to bipolar disorder with psycho-disorder, psychotic bipolar disorder, and nonpsychotic sis/bipolar disorder without psychosis to schizoaffective bipolar disorder) and clarified their relationship to clinical disorder/schizophrenia and were strongly related to gen- and cognitive features. eral cognitive function (r50.91). P50 responses to standard trials and early beta/gamma frequency responses Methods: Auditory oddball responses to standard and tar-separated the bipolar disorder without psychosis group get tones from 64 sensor EEG recordings were compared from the bipolar disorder with psychosis group. P200, across patients with psychosis (total N5597; schizophrenia, N200, and late beta/gamma frequency responses sepaN5225; schizoaffective disorder, N5201; bipolar disorder rated the two bipolar disorder groups from the other with psychosis, N5171), patients with bipolar disorder groups. without psychosis (N566), and healthy comparison subjects (N5415) from the second iteration of the Conclusions: Neural deviations during auditory processing Bipolar-Schizophrenia Network for Intermediate Phenoare related to psychosis history and bipolar disorder. There types (B-SNIP2) study. EEG activity was analyzed in voltage is a powerful transdiagnostic relationship between severity and in the time-frequency domain (low, beta, and gamma of these neural deviations and general cognitive perforbands). Event-related potentials (ERPs) were compared mance. These results have implications for understanding with those from an independent sample collected during the neurobiology of clinical syndromes across the the first iteration of B-SNIP (B-SNIP1; healthy subjects, schizophrenia-bipolar spectrum that may have an impact N5211; psychosis group, N5526) to establish the repeat-on future biomarker research. ability of complex oddball ERPs across multiple psychosis syndromes (r values .0.94 between B-SNIP1 and B-SNIP2). Am J Psychiatry 2021; 178:952–964; doi: 10.1176/appi.ajp.2021.20071043