A 22-year-old college student with no prior psychiatric history presents with a first episode of psychosis following a period of severe academic stress, sleep deprivation, and social isolation. Family history reveals that his mother has schizophrenia and his maternal uncle had schizoaffective disorder. Genetic testing identifies several common risk variants in genes encoding the DISC1 protein and COMT enzyme. The PMHNP is formulating a neurobiological understanding of this patient's presentation. Which of the following best applies the stress-diathesis model to this clinical scenario?