Hypotheses of the Pathophysiology of Schizophrenia Spectrum Disorders

Schizophrenia spectrum disorders (SSD) manifest multidimensionally, presenting a syndromic nature with several symptomatic domains. These are driven by dynamic systemic biological changes that unfold over the course of the disease. In this chapter, we present a summary of the main hypotheses that have evolved over time to explain the pathophysiology of SSD and that have driven the discovery of associated biomarkers—neurotrophic, neurotransmitter, neuroendocrine, immune-inflammatory, nitrosative/oxidative stress, metabolic, and gut microbiota-brain axis—with the aim of showing the most relevant research carried out in the last twelve years to develop predictive or diagnostic models based on these biomarkers.