Foundations: Biopsychosocial Model, Mind-Body Relationships, and Scientific Bases
Core concepts
The biopsychosocial model (Engel) treats health and illness as products of interacting biological, psychological, and social systems rather than a single linear cause. Know the diathesis-stress framing (a vulnerability plus a stressor produces disorder), allostasis and allostatic load (cumulative physiologic wear from repeated adaptation), and the HPA axis and autonomic pathways through which stress becomes biology. Familiarize yourself with psychoneuroimmunology basics (stress-related immune modulation), the difference between disease (pathology) and illness (the lived experience), and the placebo/nocebo literature as evidence that expectancy is a real biologic variable.
Traps
Questions often reward the multilevel answer over the elegant single-cause one. Watch for confusion between allostasis (adaptive process) and allostatic load (the cost). Another trap: equating correlation with causation in stress-illness research-know that cross-sectional designs cannot establish direction, and that prospective cohorts and randomized trials carry different weight. Candidates also miss that the biopsychosocial model is a framework, not a testable theory, and that it is frequently misapplied as "psychological factors cause everything."
Worked example
A patient with chronic low back pain and depression: a reductionist answer treats the pain as purely structural; a biopsychosocial answer integrates nociceptive input, catastrophizing and mood, and work/family reinforcement contingencies. Rule of thumb: if an option names only one level of analysis, it is usually the distractor.
Study tip
Map each construct to its measurement level (biology, behavior, social context) before answering; the level requested by the stem is often the discriminator.