Recent neuroscientific advances pinpoint cellular and molecular pathways underlying complex disorders. Single-nuclei RNA sequencing reveals PTSD leaves distinct gene expression "scars" in specific brain cell types, explaining drug response differences with depression. Parkinson’s researchers link minor hallucinations to progression towards vivid visual hallucinations, enhancing disease understanding. Separately, hypothalamic metabolic inflammation is implicated in adolescent reproductive dysfunction, reframing neuroendocrine regulation in reproductive health.