Difficulty: Introductory | Prerequisites: None
These three chapters lay the groundwork for the entire course. Chapter 1 defines health psychology and its research methods. Chapter 2 covers the body's major systems and the social factors that shape health outcomes. Chapter 3 introduces prevention frameworks and the models used to explain why people change (or do not change) health behaviours. If you are coming in cold, start here.
Health psychology studies how biological, psychological, and social factors interact to influence health and illness. The field exists largely because chronic diseases have replaced infectious diseases as the leading causes of death, and most chronic conditions are tied to behaviour. To change those behaviours, researchers use models such as the Health Belief Model and the Transtheoretical Model, while prevention efforts are organised through frameworks like Caplan's primary/secondary/tertiary model and the IOM's universal/selective/indicated model.
Health psychology
The subfield of psychology devoted to understanding how psychological, behavioural, and social factors influence health, illness, and health care. Think of it as the study of why people do (or do not do) the things that keep them well.
Wellness
A state of optimal health that goes beyond the mere absence of disease, encompassing physical, mental, and social well-being. In simple terms, being "not sick" is not the same as being well.
Biopsychosocial model
A framework holding that health and illness result from the interplay of biological factors (genetics, physiology), psychological factors (cognition, emotion, behaviour), and social factors (culture, socioeconomic status, relationships). Think of it as the replacement for the older biomedical model, which treated health as purely a matter of biology.
Chronic illness
A long-lasting condition that can be managed but typically not cured (e.g. heart disease, diabetes, asthma). This matters for the course because chronic illnesses are now the leading cause of death, and most are linked to lifestyle and behaviour.
Experiment
A research design in which the researcher manipulates an independent variable and randomly assigns participants to conditions, allowing causal conclusions. The advantage is internal validity; the disadvantage is that some health-relevant variables cannot ethically be manipulated.
Correlational study
A research design that measures the relationship between two or more variables without manipulation. It can reveal associations but cannot establish cause and effect. In simple terms, correlation tells you things move together, not that one causes the other.
Meta-analysis
A statistical technique that combines results from multiple studies to estimate an overall effect. Potential problems include publication bias (positive results are published more often), combining studies that differ in quality, and the "file drawer" problem.
Social determinants of health
Conditions in the environments where people are born, live, work, and age that shape health outcomes, including income, education, neighbourhood safety, and access to care. Think of it as the structural backdrop that makes healthy choices easier or harder depending on who you are.
Caplan's model of prevention
A three-tier prevention framework: primary prevention (preventing disease before it occurs), secondary prevention (early detection and intervention), and tertiary prevention (managing existing disease to reduce complications).
IOM prevention model
The Institute of Medicine's framework that classifies prevention as universal (aimed at the general population), selective (aimed at groups with elevated risk), or indicated (aimed at individuals already showing early signs).
Health Belief Model (HBM)
A model proposing that health behaviour is influenced by perceived susceptibility, perceived severity, perceived benefits, perceived barriers, cues to action, and self-efficacy. In simple terms, people weigh how likely and how bad a health threat is against how hard and how useful a behaviour change would be.
Theory of Planned Behaviour (TPB)
A model stating that behavioural intention is shaped by attitudes toward the behaviour, subjective norms (what others think), and perceived behavioural control. Intention, in turn, predicts behaviour.
Self-Determination Theory (SDT)
A theory that motivation is strongest when three psychological needs are met: autonomy (feeling in control), competence (feeling capable), and relatedness (feeling connected to others).
Motivational Interviewing (MI)
A collaborative, client-centred counselling style that helps people explore and resolve ambivalence about behaviour change. It works with the person's own motivation rather than imposing external pressure.
Transtheoretical Model (TTM) / Stages of Change
A model describing behaviour change as a process through stages: precontemplation, contemplation, preparation, action, and maintenance. People can move forward and backward through these stages.
Cognitive-behavioural approaches
Interventions that target the relationship between thoughts, feelings, and behaviours. The core idea is that changing maladaptive cognitions can change behaviour and emotional responses.
Health psychologists work across four areas:
Health promotion and maintenance: encouraging behaviours that keep people healthy (exercise, diet, sleep)
Prevention and treatment of illness: designing interventions to prevent disease and improve outcomes for those already ill
Aetiology of illness: identifying psychological, behavioural, and social causes and correlates of disease
The health care system and health policy: studying how people interact with providers, how the system can be improved, and how policy shapes access
The biopsychosocial model replaced the older biomedical model, which assumed that disease could be explained entirely by biological malfunction. The biopsychosocial model insists that biological processes (genetics, immune function), psychological processes (beliefs, coping styles, stress), and social processes (culture, poverty, social support) all contribute to health and illness. This is the organising framework for the entire course.
The field grew in importance because of the epidemiological transition: infectious diseases (tuberculosis, influenza) were once the leading killers, but chronic illnesses (heart disease, cancer, diabetes) have taken their place. Chronic conditions are strongly linked to behaviour, which means psychology has a direct role to play. The ageing population amplifies this: as people live longer, they accumulate more chronic conditions, and the system needs approaches that go beyond prescribing medication.
Experiments
The researcher manipulates an independent variable and randomly assigns participants
Advantage: allows causal inference ("X causes Y")
Disadvantage: some variables cannot ethically or practically be manipulated (you cannot randomly assign people to smoke for 20 years)
Correlational studies
Measure two or more variables and assess the relationship between them
Advantage: can study variables that cannot be manipulated; useful in natural settings
Disadvantage: cannot establish causation; third-variable problem is always present
Meta-analysis
Statistically combines findings from multiple studies
Potential problems: publication bias, heterogeneity among included studies, quality of original studies varies, the "file drawer" problem (non-significant findings go unpublished)
Duke University researchers found that psychological and social factors have measurable effects on biological systems, reinforcing the biopsychosocial model. Their work demonstrated that stress, mood, and social relationships can alter physiological functioning, which is why health psychologists need to understand the body's systems.
Hindbrain
Medulla: controls basic life functions (heart rate, breathing, blood pressure)
Pons: involved in sleep, arousal, and relaying signals between the cerebellum and cortex
Cerebellum: coordinates fine motor movement and balance
Midbrain
The midbrain is a relay station for auditory and visual information and plays a role in motor control and arousal.
Forebrain
Cerebral cortex: the outer layer of the brain responsible for higher-order thinking, divided into four lobes
Frontal lobe: planning, decision-making, personality
Parietal lobe: sensory processing, spatial awareness
Temporal lobe: auditory processing, memory, language comprehension
Occipital lobe: visual processing
Thalamus: the sensory relay station; routes incoming information (except smell) to the appropriate cortical area
Hypothalamus: regulates hunger, thirst, body temperature, and the endocrine system; central to the stress response
Lifestyle factors such as diet, exercise, sleep, and substance use are major determinants of health. Barriers to adopting healthy lifestyles include poverty, lack of access to healthy food or safe spaces for exercise, cultural norms, low health literacy, and psychological factors like stress and low self-efficacy.
Social determinants include income, education, employment, neighbourhood conditions, and access to health care. These structural factors create health disparities: people with fewer resources face greater exposure to risk and fewer opportunities to engage in health-promoting behaviour. This concept recurs throughout the course, particularly in Chapters 5 and 6.
Caplan's Model of Prevention
Primary prevention: actions taken before disease develops; targets the general population (e.g. vaccination campaigns, health education in schools)
Secondary prevention: early detection and intervention once a disease process has begun but before symptoms are severe (e.g. screening programmes such as mammography)
Tertiary prevention: managing and reducing the impact of an existing chronic condition (e.g. cardiac rehabilitation after a heart attack)
IOM Model of Prevention
Universal: interventions directed at the entire population regardless of risk (e.g. public health messages about handwashing)
Selective: interventions targeting subgroups with above-average risk (e.g. smoking cessation programmes for adolescents in high-risk neighbourhoods)
Indicated: interventions for individuals who already show early signs or symptoms (e.g. counselling for someone with pre-diabetic blood sugar levels)
Overlap and differences: Both models aim to prevent disease, but Caplan's model is organised by the stage of disease (before, during, after), while the IOM model is organised by the level of risk of the target population. Primary prevention and universal prevention overlap substantially, but the frameworks diverge as you move along each continuum.
Health Belief Model (HBM)
Proposes that behaviour change depends on six factors: perceived susceptibility ("How likely am I to get this?"), perceived severity ("How bad would it be?"), perceived benefits ("Will this action help?"), perceived barriers ("What stands in my way?"), cues to action (reminders or triggers), and self-efficacy ("Can I do this?").
Theory of Planned Behaviour (TPB)
Behavioural intention is the strongest predictor of behaviour, and intention is shaped by three things: your attitude toward the behaviour, subjective norms (whether people important to you approve), and perceived behavioural control (whether you believe you can perform the behaviour). Note that perceived behavioural control can also directly influence behaviour, bypassing intention.
Cognitive-Behavioural Approaches
Focus on identifying and modifying maladaptive thought patterns and behaviours. Techniques include self-monitoring, goal setting, stimulus control, and cognitive restructuring. Widely used in smoking cessation, weight management, and pain management.
Self-Determination Theory (SDT)
People are most motivated when three basic needs are satisfied: autonomy (choosing for yourself), competence (feeling effective), and relatedness (feeling connected). Intrinsic motivation (doing something because you find it meaningful) produces more durable behaviour change than extrinsic motivation (doing it for a reward or to avoid punishment).
Motivational Interviewing (MI)
A collaborative counselling technique built on empathy, developing discrepancy between current behaviour and goals, rolling with resistance rather than confronting it, and supporting self-efficacy. It is non-judgmental and works by helping the person articulate their own reasons for change.
Transtheoretical Model (TTM)
Describes behaviour change as movement through stages:
Precontemplation: not thinking about changing
Contemplation: aware of the problem, considering change but not committed
Preparation: intending to act soon, making small steps
Action: actively modifying behaviour
Maintenance: sustaining the new behaviour over time
Relapse is normal and does not mean failure; people cycle through stages. Interventions should be matched to the person's current stage.
Students often think the biopsychosocial model simply means "biology plus psychology plus sociology." It does not. The model emphasises the interaction among these factors, not just their co-existence. A strong exam answer explains how one factor amplifies or moderates another.
Students frequently confuse correlation with causation when reading health research. A correlational study can show that stress and illness are related, but it cannot tell you that stress caused the illness. Always check for a third-variable explanation.
Students mix up primary prevention (Caplan) with universal prevention (IOM). They overlap considerably, but primary prevention is defined by timing (before disease starts), while universal prevention is defined by audience (everyone, regardless of risk).
Students assume the Transtheoretical Model is linear. It is not. People cycle through stages and may revisit earlier stages multiple times before sustaining change.
The biopsychosocial model is foundational. Expect questions asking you to identify which factor (biological, psychological, social) is at play in a given scenario, or to explain why the biomedical model is insufficient.
Know the advantages and disadvantages of each research method cold. A multiple-choice question might describe a study and ask you to identify the design and its limitations.
Be able to distinguish Caplan's model from the IOM model and explain where they overlap. This is a common comparison question.
For behaviour change models, know what makes each one distinct. The HBM centres on perceived threat and cost-benefit analysis. The TPB adds social norms and perceived control. SDT focuses on intrinsic motivation. MI is a counselling style, not a predictive model. The TTM is stage-based.
The shift from acute infectious diseases to chronic lifestyle-related diseases is the reason health psychology exists as a field. This context question appears regularly.
True or False: The biomedical model considers psychological and social factors in explaining illness. (False)
Fill in the blank: The three components of the biopsychosocial model are ______, ______, and ______. (Biological, psychological, social)
True or False: A correlational study can establish that one variable causes changes in another. (False)
Fill in the blank: In the Transtheoretical Model, a person who is not yet thinking about changing their behaviour is in the ______ stage. (Precontemplation)
True or False: Primary prevention (Caplan) and universal prevention (IOM) mean exactly the same thing. (False, they overlap but are defined differently)
Q: A researcher wants to determine whether a new stress-management programme causes a reduction in blood pressure. What type of study design should they use, and why?
A: An experiment, because establishing causation requires manipulating an independent variable (the programme) and randomly assigning participants to conditions. A correlational study could show a relationship but could not confirm the programme caused the change.
Q: A public health campaign encourages all adults to get an annual flu vaccine. Under Caplan's model and the IOM model, how would you classify this intervention?
A: Under Caplan's model, this is primary prevention (it aims to prevent disease before it starts). Under the IOM model, it is universal prevention (it targets the general population regardless of individual risk).
Q: According to the Health Belief Model, what factors would influence whether a university student decides to start wearing sunscreen daily?
A: Perceived susceptibility ("I could get skin cancer"), perceived severity ("Skin cancer is serious"), perceived benefits ("Sunscreen reduces my risk"), perceived barriers ("It's greasy and expensive"), cues to action (a friend's diagnosis, a public health poster), and self-efficacy ("I can remember to apply it each morning").
Q: How does Self-Determination Theory differ from the Health Belief Model in explaining motivation for behaviour change?
A: The HBM focuses on cognitive appraisal of threat and cost-benefit analysis. SDT focuses on whether three basic psychological needs are met: autonomy, competence, and relatedness. SDT emphasises the quality of motivation (intrinsic vs. extrinsic), while the HBM emphasises rational calculation of risk.
Q: A patient knows smoking is harmful, has considered quitting, and has set a quit date for next month. What stage of the Transtheoretical Model are they in?
A: Preparation. They have moved past contemplation (merely considering change) and are making concrete plans to act, but have not yet begun the new behaviour.
The biopsychosocial model from Chapter 1 is the lens through which every later topic is examined. Social determinants of health (Ch. 2) reappear in the discussions of chronic stress and weathering (Ch. 6), health-compromising behaviours (Ch. 5), and health disparities in chronic disease (Ch. 13). The behaviour change models from Chapter 3 are applied directly in Chapters 4 (health-promoting behaviours) and 5 (health-compromising behaviours), and their principles underpin the psychological interventions discussed in Chapters 7, 10, and 11.
Related Terms / Search Tags
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