Restoring Spindle and Thalamocortical Efficiency in Early-Course Schizophrenia Patients Using Auditory Stimulation

The overarching goal of the proposed study is to establish sleep spindle and slow wave abnormalities as early pathophysiological biomarkers of schizophrenia (SCZ). The investigators also seek to enhance spindle and slow wave deficits in EC-SCZ by utilizing a closed-loop auditory stimulation during sleep. The investigators will assess improvement of deficits with the use of a memory consolidation task before and after sleeping. Participants will include early-course schizophrenia (EC-SCZ) subjects and healthy controls (HC). Participants will complete several assessments, including clinical evaluation, an IQ assessment (WASI), and at least 2 nights of sleep EEG recordings in the sleep clinic of UPMC Western Psychiatric Hospital with a polysomnography test (PSG) each night. Study participants will also fill out a Pittsburgh Sleep Quality Index (PSQI) which reports sleep habits. On one of the nights, EC-SCZ participants will receive active closed-loop auditory stimulation, while on another night they will receive sham closed-loop auditory stimulation. On all nights beside the adaptation night (night 1) participants will complete the motor sequence task (MST) and the AX-continuous performance task (AXCPT) before going to sleep. They will also repeat the task the following morning. There will be \~1 week between nights 2 and 3 and \~1 week between nights 3 and 4. Aim 1. Establish sleep spindle and slow wave deficits in EC-SCZ patients relative to HC using a wireless ambulatory monitor. H1a. EC-SCZ patients will have reduced sleep spindle duration and density compared to HC. H1b. Slow wave density will be decreased in EC-SCZ patients relative to HC. Aim 2. Determine that spindle and slow wave impairments can be acutely improved in EC-SCZ patients using closed-loop auditory stimulation during sleep. H2a. Sleep spindle duration and density will increase during closed-loop auditory stimulation nights compared to baseline and sham intervention. H2b. Slow wave density will increase during stimulation nights relative to baseline and sham intervention. Aim 3. Examine the relationship between spindle and slow wave deficits and memory consolidation before and after their acute improvement in EC-SCZ patients relative to HC. H3a. At baseline, sleep spindles and slow waves will predict memory consolidation in EC-SCZ patients and HC. H3b. An increase in sleep spindles and slow waves during stimulating night will be associated with task-assessed memory consolidation improvement in EC-SCZ patients relative to baseline performance.