Diathesis-stress model – IB Psychology Study Notes

Comprehensive IB Psychology study notes on Diathesis-stress model. Covers key theories, research studies, and evaluation points for the 2027 syllabus.

Mark Scheme SECTION A MARK SCHEME 4 marks Must Include: • Diathesis: biological vulnerability/genetic predisposition • Stress: environmental trigger/stressor • Threshold concept: both needed to exceed threshold • Interactionist framework nature + nurture • Named condition e.g. schizophrenia • Specific stressor example e.g. cannabis use, urban environment • Show why either alone is insufficient Link Formula: "Condition results from genetic diathesis combined with specific environmental stressor; ...