Psychology

Psychology is the scientific study of the mind and behavior. It looks at both humans and animals. Psychologists study thoughts, feelings, and why people act the way they do. This field connects the natural and social sciences.

Some psychologists focus on how the brain works, linking their work to neuroscience. Others study how people and groups behave.

Professionals in this area are called psychologists. They study how thinking affects how people act, both alone and together. Psychology is an interdisciplinary field. Researchers explore topics like perception, cognition, emotion, intelligence, motivation, brain functioning, and personality.

Psychologists also look at interpersonal relationships and how people stay strong in tough times. They use careful research methods to understand the mind and behavior. Many psychologists help people with mental health through psychotherapy. Others work in schools, businesses, or study topics like human development, sports, and education. Psychology aims to help improve lives in many ways.

Etymology and definitions

The word psychology comes from the Greek word psyche, meaning spirit or soul, and -logia, meaning "study" or "research". People began using the word psychology during the Renaissance. Since then, it has been used to talk about the mind and behavior.

William James described psychology as the science of mental life. Others, like John B. Watson, studied behavior through experiments. Today, psychology is a science that looks at how our minds and behaviors work.

History

Main article: History of psychology

For a chronological guide, see Timeline of psychology.

The ancient civilizations of Egypt, Greece, China, India, and Persia studied ideas about the mind. In Ancient Egypt the Ebers Papyrus talked about thought problems. Greek thinkers like Thales, Plato, and Aristotle discussed how the mind works. In 387 BCE, Plato said the brain is where thinking happens. In 335 BC, Aristotle said it was the heart.

In China, old thinkers like Laozi and Confucius talked about cleaning the mind to grow virtue. Buddhism also shaped Chinese ideas. An old book, The Yellow Emperor's Classic of Internal Medicine, said the brain is where wisdom and feeling come from. Chinese learning grew during the Qing dynasty.

Psychology interested thinkers in Europe during the Enlightenment. In Germany, Gottfried Wilhelm Leibniz used math ideas to understand the mind. Christian Wolff said psychology was its own science. Immanuel Kant helped create the study of anthropology, which includes psychology.

Beginning of experimental psychology

The thinker John Stuart Mill believed the mind could be studied with science. Gustav Fechner started testing mental processes in the 1830s. In Heidelberg, Hermann von Helmholtz studied how we sense things. He trained Wilhelm Wundt. Wundt went to Leipzig University and started the first lab for experimental psychology.

James McKeen Cattell was the first psychology teacher in the United States. He worked at the University of Pennsylvania and Columbia University.

The German psychologist Hermann Ebbinghaus studied how memory works. In the early 1900s, Wolfgang Kohler, Max Wertheimer, and Kurt Koffka started Gestalt psychology. Gestalt psychology says we see things as whole pictures, not just parts.

Psychologists in many countries started labs like Wundt’s. G. Stanley Hall started a famous lab at Johns Hopkins University.

Another student of Wundt, Edward Titchener from England, started a psychology program at Cornell University and worked on "structuralist" psychology. William James, John Dewey, and Harvey Carr worked on functionalism, a bigger view of psychology. In 1890, James wrote a well-known book, The Principles of Psychology.

In South America, Horacio G. Piñero led new ideas at the University of Buenos Aires. In Russia, Ivan Sechenov talked about the brain’s role in psychology. Ivan Pavlov discovered a way learning happens called "classical conditioning".

Consolidation and funding

One of the first psychology groups was La Société de Psychologie Physiologique in France. The first meeting of the International Congress of Psychology was in Paris in August 1889. The American Psychological Association (APA) started in 1892.

American psychology grew after the U.S. entered World War I. Then, the Rockefeller family gave money for research. In the 1910s and 1920s, the eugenics movement affected American psychology.

During World War II and the Cold War, the U.S. military helped pay for psychology research. In Germany after World War I, psychology had power through the military. After the war, new schools started.

After the Russian Revolution, the Bolsheviks wanted psychology to help build a new society. Many students studied psychology in universities.

Twentieth-century Chinese psychology started like U.S. psychology. After the Chinese Communist Party took control, ideas from the Soviet Union became important.

Women in psychology

Main articles: List of women psychologists and Female psychology

1900–1949

Women in the early 1900s started to help shape psychology. In 1923, Anna Freud, the daughter of Sigmund Freud, studied children’s minds.

Functional periodicity, an old idea that women’s minds and bodies change during menstruation, affected women's rights. Leta Stetter Hollingworth tested this and found it was not true. She tested women and men for three months and found no change in women’s work during their menstrual time.

New ideas in the first half of the 1900s helped women gain respect in psychology. Leta Stetter Hollingworth and Anna Freud were important. Mary Whiton Calkins created a way to study memory. Karen Horney talked about “womb envy” and nervous needs. Melanie Klein studied children with play therapy and helped developmental psychology.

1950–1999

Women in the second half of the 20th century kept doing important work in psychology. Mary Ainsworth studied how babies bond, and her work is very well known. Mamie Phipps Clark also changed psychology with her research.

As psychology grew, women worked to be heard and valued.

The later part of the 20th century saw more women of color reaching new goals. In 1962, Martha Bernal became the first Latina woman with a Ph.D. in psychology. In 1969, Marigold Linton, the first Native American woman with a Ph.D. in psychology, started the National Indian Education Association. In 1971, Carolyn Attneave created the Network of Indian Psychologists.

21st century

In the 21st century, women have become more important in psychology and work in many areas. Many now lead research labs. But women still earn less and hold fewer top jobs. More women than ever are studying psychology. In the United States, about 78% of undergraduate students and 71% of graduate students in psychology are women.

Disciplinary organizations

See also: List of psychology organizations

In 1920, Édouard Claparède and Pierre Bovet started a group called the International Association of Applied Psychology. Today, there are many groups around the world that study psychology. The International Union of Psychological Science (IUPsyS) began in 1951 to connect these groups.

The American Psychological Association is the biggest group for psychologists, with many members. It has smaller groups that focus on different areas of psychology. Other groups, like the Interamerican Psychological Society, help share psychology ideas between regions.

Major schools of thought

Biological

Psychologists study how our biology shapes our thoughts and feelings. Behavioral neuroscience looks at how our bodies, especially the brain, affect our actions. Important discoveries came from studying people with brain damage, which showed how different parts of the brain control different skills.

Modern behavioral neuroscience started in the 1870s when scientists found brain areas linked to speech. Today, scientists study animals to learn about memory, and use special tools to watch brain activity in people. The biopsychosocial model shows how our biology, thoughts, and environment all work together to shape our actions.

Behaviorist

Behaviorism studies how we learn from our environment. Early behaviorists looked at how animals and people learn from rewards and punishments. They discovered that neutral things can become signals for certain reactions when they are repeatedly paired with important events.

John B. Watson started behaviorism, and B.F. Skinner added ideas about reinforcement and punishment. Noam Chomsky later suggested that behaviorism could not fully explain complex thinking, like language. Behaviorism is still helpful today in teaching people new habits.

Cognitive

Cognitive psychology studies our mind, such as perception, attention, memory, and solving problems. Scientists use models to understand how our mind works. This field grew in the 1950s with better technology to study mental states.

Cognitive psychology looks at how we think, including mistakes we might make. It also studies how we learn by watching others, not just from rewards. Cognitive science combines psychology, computer science, and neuroscience to better understand the mind.

Social

Social psychology looks at how people affect each other's thoughts, feelings, and actions. It studies topics like following the crowd, persuasion, and stereotypes. Social psychologists also study how groups behave and what makes a good leader.

Psychoanalytic

Psychoanalysis studies the unconscious mind and how it affects our daily lives. It was started by Sigmund Freud and includes methods like free association and dream interpretation. Over time, many different approaches to psychoanalysis developed.

Existential-humanistic

Humanistic psychology focuses on personal growth, free will, and understanding yourself. It began in the 1950s as an alternative to behaviorism and psychoanalysis. Important thinkers include Abraham Maslow and Carl Rogers.

Positive psychology studies what helps people feel happy and well, building on humanistic ideas. Existential psychology looks at how people find meaning in life, especially when thinking about big questions. Viktor Frankl created logotherapy, which focuses on finding personal meaning, even in hard times.

Main article: Cognitive neuroscience

Main articles: Behaviorism, Psychological behaviorism, and Radical behaviorism

Main article: Cognitive psychology

Main article: Social psychology

See also: Social psychology (sociology)

Main articles: Psychodynamics and psychoanalysis

Main articles: Existential psychology and Humanistic psychology

Themes

Personality psychology studies how people behave, think, and feel over time. Different ideas try to explain these patterns. Some focus on traits, like how outgoing or anxious a person might be.

The idea of an unconscious mind—thoughts and feelings we aren’t aware of but that still affect us—has been important in psychology. Things we don’t notice can still shape our actions.

Motivation explains why people do things. It includes basic needs like hunger and thirst, as well as desires to belong or feel good about ourselves.

Developmental psychology looks at how people’s thinking, feelings, and behaviors change throughout their lives. Researchers watch children and create fun activities to learn about their development. They also study how genes and environment together shape who we are.

Applications

Psychology studies how people think, feel, and act in different situations. It has many useful applications.

Psychological testing

Psychological testing began with old exams for government jobs in China. Now, scientists use these tests in schools and workplaces to learn about people's skills and abilities.

Mental health care

Mental health care helps people deal with emotional and mental challenges. Psychologists work with individuals and families to offer support and guidance. They use talking therapies to help people manage their feelings and improve their lives.

Education

Educational psychology looks at how people learn and how to teach well. It helps teachers create better learning places and methods. This field uses ideas from famous psychologists who studied how children grow and learn.

Work

Industrial and organizational psychology uses psychology to improve workplaces. It helps companies find the right people, create good work places, and support employee well-being. This field studies how people act at work and how to make jobs better and more satisfying.

Military and intelligence

Psychologists help military forces support soldiers' mental health and provide guidance. They assist with counseling and treating mental health issues that can come from military service.

Health, well-being, and social change

Psychologists work to improve public health and well-being. They help people develop healthier habits, support community policies, and study how work places affect health. Their research has helped change laws and practices to make workplaces and societies safer and healthier.

Research methods

Main articles: Psychological research and List of psychological research methods

Psychology studies how the mind and behavior work. It uses many ways to learn about this.

One way is quantitative research. This uses numbers to test ideas. Psychologists do experiments in labs where they can control things. They might change one thing to see how it affects another, like studying how learning happens.

Another way is qualitative research. This looks closely at people's thoughts and feelings. It can include interviews or watching people in real-life. Both types of research help psychologists understand how we think, feel, and act.

Controlled experiments

Main article: Experiment

In controlled experiments, researchers change one factor to see what happens. This helps them understand why things occur. Sometimes, they study groups that already exist instead of creating new ones.

Other types of studies

Further information: Video recall

Psychologists also use surveys. These ask people about their attitudes or feelings. They might use paper, phone, or online forms. Observational studies watch people over time to see changes. Some studies happen once, while others follow the same group for years.

Direct brain observation/manipulation

A tool called the electroencephalogram (EEG) measures brain activity using sensors on the head. Newer tools like functional magnetic resonance imaging (fMRI) show which parts of the brain are active during tasks. These help scientists learn about the brain and mind.

Computer simulation

Computers help psychologists simulate how people think and behave. This lets them test ideas quickly and spot patterns that might be hard to see otherwise.

Animal studies

Animals are sometimes used in research to understand human behavior. For example, Ivan Pavlov used dogs to study learning. While this can give useful clues, animals aren’t exactly like humans.

Qualitative research

Qualitative research looks at people’s thoughts and feelings in detail. It uses methods like interviews and watching people in everyday life. This helps psychologists understand experiences that numbers might miss.

Program evaluation

This checks whether programs or policies work as intended. It looks at success, costs, possible improvements, and unintended results.

Contemporary issues

Metascience studies how to make science better. It found that some psychology research has problems, like being hard to repeat or using statistics incorrectly. This has led to calls for better ways to check and share research results.

Researchers noticed that most psychology studies are done with people from Western, educated, industrialized, rich, and democratic countries, called "WEIRD" societies. These groups are only a small part of the world’s population, so findings might not apply to everyone. Scientists are now trying to include more diverse groups in their studies to make their results more useful worldwide.

Ethics

Ethical standards in psychology have grown over time. Some past studies are now seen as wrong because they broke important rules. Today, psychologists must ask for permission from people before including them in studies. They must also make sure participants understand what they are agreeing to.

Key ethical rules include doing good, not causing harm, being honest, treating everyone fairly, and respecting people's privacy. These rules help psychologists protect the people they work with and keep trust in the field. Universities have special groups that check research to make sure it follows these rules.