A Constraint-Based Framework for Architectural Evaluation in Schizophrenia Research

Despite decades of intensive research, schizophrenia remains characterized by theoretical fragmentation and limited integrative convergence. This concept paper proposes a constraint-based framework for comparatively evaluating explanatory coverage in schizophrenia research, shifting emphasis from isolated mechanisms to recurring structural features emphasized across theoretical and empirical literatures. Twenty-five constraints are formalized, comprising ten observed constraints derived from recurrent clinical and phenomenological regularities (C1–C10) and fifteen empirically established constraints grounded in replicated findings across genetics, neuroscience, epidemiology, pharmacology, and longitudinal outcomes (E1–E15). Major explanatory approaches—including dopaminergic, glutamatergic, neurodevelopmental, and computational accounts—are examined with respect to their explicit alignment with this constraint set using predefined analytic criteria. This analysis illustrates systematic differences in how existing models address issues such as causal direction, state–trait distinction, longitudinal sensitivity, and cross-system interaction. On this basis, the framework is used to outline a provisional specification of architectural features that may warrant further investigation in future theoretical and empirical work. The Sensitivity Threshold Model (STM) is presented as one candidate architecture that exhibits broad alignment with the full constraint set, serving as an illustrative application rather than a validated solution. The primary contribution of this work is the introduction of a structured, transparent methodological heuristic intended to facilitate comparison, clarify evidentiary expectations, and support cumulative theory development in schizophrenia research.