Pharmacologically-augmented Cognitive Therapies (PACTs) for Schizophrenia.

MH59803 demonstrated that AMPH (20 mg p.o.) significantly increased PPI and neurocognitive performance (MATRICS Consensus Cognitive Battery; MCCB) in HS characterized by specific performance-based or genetic biomarkers, including the val/val genotype for the rs4680 polymorphism of catechol-O-methyltransferase (COMT). Mechanistically-informative results were detected in studies of AMPH effects on PPI in rats with high vs. low brain regional Comt expression. Together with several reports of improved neurocognition and no adverse effects of acute or sustained AMPH administration to antipsychotic (AP)-medicated SZ/SZA patients, MH59803 findings provide a strong rationale for the next goal of this application: to test the potential utility of AMPH in a paradigm of biomarker-informed "PACTs". This "next step" is highly innovative - never previously reported, or perhaps even attempted - and consistent with National Institute of Mental Health (NIMH) objectives, directly challenges existing models for SZ/SZA therapeutics. Investigators will determine whether a test dose of 10 mg AMPH p.o. administered to biomarker-identified, AP-medicated SZ/SZA patients generates predicted increases in PPI, MCCB performance, and sensory discrimination learning in a Targeted Cognitive Training (TCT) module. In total, Investigators will leverage knowledge generated through converging cross-species studies in MH59803, to directly advance scientific and clinical domains, by testing the effects of a pro-cognitive drug on neurophysiological and neurocognitive performance, and Targeted Cognitive Training, in biomarker-stratified subgroups of SZ/SZA patients. Aim: To assess acute effects of AMPH (0 vs 10 mg po) on PPI, neurocognition and computerized TCT in AP-medicated SZ/SZA patients. Hypothesis: PPI- and MCCB-enhancing effects of AMPH seen previously in HS will also be detected in SZ/SZA patients, as will TCT-enhancing effects of AMPH. Prediction: In a within-subject, placebo-controlled, randomized design, AMPH (10 mg po) will increase PPI and enhance MCCB and TCT performance in medicated SZ/SZA patients, particularly among those characterized by low basal performance levels and/or the val/val rs4680 COMT polymorphism. Concurrent HS testing will confirm and extend findings of AMPH effects on PPI and neurocognition, and help interpret findings in SZ/SZA patients. In all participants, the aim to assess acute effects of 0 vs. 10 mg po dextroamphetamine (AMPH) on Prepulse Inhibition (PPI), neurocognition MATRICS: Consensus Cognitive Battery; MCCB, and computerized Targeted Cognitive Training (TCT). Hypothesis: AMPH will enhance: 1. PPI 2. neurocognition (MCCB performance) 3. computerized TCT performance in biomarker-identified SZ/SZA patients. 4. The PPI and MCCB-enhancing effects of AMPH seen previously in HS will also be detected in SZ/SZA patients, as will TCT-enhancing effects of AMPH. Prediction: In a within-subject, placebo-controlled, randomized design, AMPH (10 mg po) will increase PPI and enhance MCCB and TCT performance in medicated SZ/SZA patients, particularly among those characterized by low basal performance levels and/or the val/val rs4680 COMT polymorphism. Concurrent HS testing will confirm and extend findings of AMPH effects on PPI and neurocognition, and help interpret findings in SZ/SZA patients.