Psychology is the scientific study of how people think, feel, and behave — but it's far from a single discipline. The field encompasses many different areas, each exploring a unique aspect of human experience.
Whether you’re considering a career change into psychology or just curious about how rich this discipline is, this guide is for you. Read on to discover the breadth and diversity of psychology, and how the University of Southampton’s online Psychology master’s conversion course could change your career trajectory.
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The main fields of psychology explained
Psychology covers an incredibly wide range of topics. Here are some of the main fields you'll encounter:
Social Psychology
Social psychology examines how people think, feel, and behave in social situations. It looks at how we're influenced by others - whether that's through peer pressure, cultural norms, or group dynamics.
Social psychologists study everything from conformity and obedience to prejudice, persuasion, and how we form relationships. They're interested in questions like: Why do we behave differently when we're alone versus in a group? How do our attitudes shape our actions? What makes us help (or ignore) strangers?
This field has practical applications in areas like marketing, organisational behaviour, public health campaigns, and conflict resolution.
In our course, you'll explore social psychology through the Personality Traits & Social Dynamics module. You'll examine how attitudes influence behaviour, how individuals influence one another, and how groups shape individual actions at intrapersonal, interpersonal, and collective levels.
Developmental Psychology
Developmental psychology explores how people grow, learn, and change throughout their lives, from infancy to old age. It examines physical, cognitive, emotional, and social development across the lifespan.
Developmental psychologists study milestones like language acquisition in children, identity formation in adolescents, and cognitive changes in older adults. They also investigate how early experiences shape later behaviour and how people adapt to life transitions.
This field informs work in education, parenting support, elderly care, and interventions for developmental disorders.
Our course includes a Developmental Psychology module, which covers human development from infancy to old age. Topics include early sensorimotor development, language acquisition, emotional development, family influences, adolescence and adulthood, and ageing and death.
Clinical Psychology
Clinical psychology focuses on understanding, diagnosing, and treating mental health conditions. Clinical psychologists work with individuals experiencing depression, anxiety, trauma, psychosis, and other psychological difficulties.
This field combines psychological theory with evidence-based treatments like cognitive behavioural therapy (CBT). Clinical psychologists assess patients, develop treatment plans, and deliver interventions designed to improve mental health and wellbeing.
It's one of the most well-known branches of psychology and requires extensive specialist training beyond a master's degree.
Our Clinical Psychology module introduces adult psychopathology, diagnostic classification models, and theoretical approaches to understanding mental disorders. You'll also study evidence-based treatments like cognitive behavioural therapy and explore their empirical foundations.
Health Psychology
Health psychology examines the psychological factors that influence physical health and illness. It explores how behaviours like exercise, diet, smoking, and sleep affect our wellbeing, and how to help people make healthier choices.
Health psychologists design and test interventions to change behaviour, support people managing chronic conditions, and promote public health. They work in settings like hospitals, public health organisations, and research institutions.
This field continues to grow as we now know that psychological factors play a bigger role in physical health outcomes than we once thought.
Our Health Psychology module covers biopsychosocial models of health, behaviour change theories and techniques. You'll learn how to design and evaluate theory-based interventions, create your own health intervention, and pilot it with real participants.
Cognitive Psychology
Cognitive psychology studies mental processes like memory, attention, perception, problem-solving, and decision-making. It asks questions like: How do we remember information? Why do we sometimes fail to notice things right in front of us? How do we make decisions under pressure?
This field has applications in education (how people learn), human-computer interaction (how to design intuitive interfaces), and even legal settings (how reliable is eyewitness testimony?).
Our Cognitive & Biopsychology module examines core cognitive processes including learning and memory, sensation and perception, attention, visual search, and object recognition. You’ll also develop a solid grasp of their neurological and biological foundations.
Biological Psychology
Also called biopsychology, this field explores the biological basis of behaviour. It examines how the brain, nervous system, hormones, and genetics influence how we think, feel, and act.
Biological psychologists study topics like how brain injuries affect personality, how neurotransmitters influence mood, and how genetics contribute to psychological traits. This field bridges psychology and neuroscience, using techniques like brain imaging to understand the mind-body connection.
Our Cognitive & Biopsychology module also covers genetic influences on behaviour and the structure of the nervous system, including neurons and neural communication. You’ll also learn about how hormones regulate development and behaviour.
Personality Psychology
Personality psychology focuses on individual differences — the unique patterns of thoughts, feelings, and behaviours that make each person distinct. It explores how personality develops, how it can be measured, and how it influences life outcomes.
Personality psychologists study trait models like the Big Five: Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism. They investigate what shapes personality (genes versus environment), and develop assessment tools used in clinical, organisational, and research settings.
Our Personality Traits & Social Dynamics module explores contemporary trait models including the Big Five and psychometric principles behind measuring personality. You'll also examine the genetic and environmental mechanisms that shape personality across the lifespan.
How will our MSc psychology benefit you?
If you're fascinated by these fields and want to build a career in psychology, the University of Southampton’s MSc Psychology conversion course covers all the core areas described above.
You'll study research-led modules covering social psychology, developmental psychology, clinical psychology, health psychology, cognitive and biological psychology, and personality psychology. The course also includes comprehensive training in research methods, learning both qualitative and quantitative approaches.
But our curriculum isn't just theory focused. You'll apply psychological concepts by designing real interventions, testing them with participants, and analysing data. Your studies will culminate in a dissertation where you develop your own research question and carry out independent psychological research from start to finish.
The course is designed specifically for career changers from any background. It's part-time and 100% online, so you can study around your existing commitments. And when you graduate, you'll be ready to pursue careers in research, health services, education, HR, and other fields where understanding behaviour matters.
Explore our psychology conversion course