Introducing psychology

ATL: Essential understandings

Psychology is the scientific study of human behaviour, cognitive processing and attitudes.

Psychology is a very broad field of study with many applications.

Concepts and theories are the building blocks of the study of human behaviour.

What is psychology?

Welcome to the world of psychology. If you are like many students, you have signed up for this class with a sense of excitement – and yet, when asked, you may not yet have a clear understanding of what psychology really is, or why it is worth studying.

Psychologists want to understand why people behave the way they do. They believe that if we can discover the causes of behaviour, we will be able to explain them, and maybe also to control them.

There is no single definition of psychology that is universally acknowledged. A common definition is: Psychology is the scientific study of the mind and behaviour. As you can see, this is a very broad definition.  

The first important part of the definition is the word “scientific”. This means a systematic and controlled study of human behaviour, with the hope of establishing either correlational or cause-and-effect relationships to describe behaviour. Psychologists do this through a range of research methods – such as experiments and observations.

TOK: Is psychology a science?

The debate about whether psychology is a science rages on the Internet.  It is without a doubt that psychologists use the scientific method.  So, why the debate?

Unlike other sciences, psychology has failed to produce a cumulative body of knowledge that has a clear conceptual core that is consensually agreed upon by mainstream psychological experts.  It is the lack of a core, accepted body of knowledge that is problematic in psychology’s desire to be labeled a “science.”

  • What are some of the core ideas that define other sciences – such as biology, chemistry, and physics? How are these core ideas most likely different from the study of human behaviour?
  • Is it important that psychology makes use of the scientific method?  Why or why not?

Psychologists study “the mind” and behaviour. The mind is defined as the part of us that reasons, thinks, feels, perceives, and judges.  Behaviour, on the other hand, is defined as the coordinated responses of whole living organisms to internal and/or external stimuli – that is, what an organism does as a result of both internal factors or environmental factors.

But actually, the study of psychology is much more complex.  Psychologists study the interaction of many internal factors  - cognitive processes, physiology, attitudes, and emotions – that influence our behaviours.

Key vocabulary

Cognitive processes  - sometimes referred to as “thought processes” – explain how the mind works.  These processes include memory, perception, attention, decision-making, and thinking/reasoning.   It is the process by which existing knowledge is used to create new knowledge.

Physiology refers to our biological systems.  Psychologists are interested in the role of our brain and nervous system, hormones, and genetics in behaviour.

Attitudes can be defined as feelings of liking or disliking toward an object, person, or idea.  You may have an attitude about Chinese food, your president, or the concept of globalization.  Our attitudes can affect our behaviour in both a positive and negative way.

Finally, emotions are a combination of physiological and cognitive processes.  According to psychologists, there are seven basic emotions: happiness, sadness, anger, fear, surprise, disgust, and contempt.

For a long part of psychology’s short history, experts argued whether behavior was the result of biological factors (nature) or environmental factors (nurture).  Today, psychologists no longer believe that it is nature or nurture – but rather, nature and nurture.  They argue that behavior is the result of the interaction of both internal and environmental factors.  As a result, psychologists look at behavior through a number of different lenses.

The IB psychology course also takes an integrative approach to studying human behaviour. This means that we will look at psychological issues through three approaches

  • The biological approach focuses on physiology, including genetics.
  • The cognitive approach focuses on mental processes like memory, thinking, perception, and attention.
  • The sociocultural approach focuses on how environment and culture affect behaviour.

An example of how these approaches are used can be seen in the study of clinical depression – or Major Depressive Disorder.  The biological approach would argue that depression is the result of biological factors – such as low levels of serotonin, high levels of stress hormones or certain combinations of genes.  The cognitive approach would argue that depression is the result of the way people think.  If your thinking is dominated by negative and pessimistic thoughts, then you are more likely to be depressed.  Finally, the sociocultural approach would argue that environmental factors – such as a stressful work environment, poverty, or war – could lead to depression. 

Obviously, it is much more complex than this, as you will learn throughout the course.

Research: Theories and empirical studies

When psychologists discuss their work, they refer to theories and make reference to empirical studies. These are some of the building blocks of scientific psychology.

A theory is an explanation for a psychological phenomenon. It is a statement used to summarize, organize, and explain observations. A theory can be used to make predictions about human behaviour. Most theories are built on concepts - that is, hypothetical constructs that must be carefully defined so that they can be tested. In order to test a concept, psychologists need to develop tools to measure it.

An example of a concept is Bandura’s self-efficacy. As a concept, self-efficacy is defined as one’s own belief as to whether one will succeed in something, based on previous experiences.

Bandura’s theory predicts that one’s self-efficacy will determine if and how hard one will try to do a certain thing. For example, a researcher might be interested in the role of self-efficacy in predicting if people will engage in regular exercise to improve their health. The researcher wants to find out if people who score high on a self-efficacy scale are more likely to engage in health-preserving behaviour than those who score low on the scale. On the basis of the findings, the researcher can either support the self-efficacy theory or question its usefulness in people’s health behaviours.

Theories in psychology are not like laws in the natural sciences. Psychological theories are probable rather than certain, and therefore they are always open to some degree of doubt. It is often the case that one theory cannot explain all aspects of a psychological phenomenon. Since this doubt is part of scientific psychology, it is necessary to evaluate theories, examining their strengths and limitations.

What makes a good theory?  A good theory is first and foremost “testable.”  This means that we could actually “prove it wrong.”  If it is not possible to test the validity of a theory, then the theory is “unfalsifiable,” and thus, not a good theory.   When we have personal experience that we can share that challenges or supports a theory, this is called anecdotal data.  For example, when I say that I know that hot weather makes people irritable and my evidence is that last week it was really hot and a shopkeeper was really unkind to me, this is anecdotal.  Psychologists do make use of anecdotal data, but in order to test theories, they use empirical evidence - that is, information acquired by observation or experimentation. 

ATL:  Thinking critically

Thinking about testability

For each of the following statements, think about whether this is "testable" or not.  If so, how would you be able to test it to see whether it is "true" or not?  What are the problems with testing these claims?

1.  Cold weather makes you sick.

2.  Married couples are happier than single people.

3.  Playing online games makes you smarter.

4.  Eating foods containing high levels of sugar can affect your concentration on a test.

An early psychological theory was posited by Otto Rank in 1924 – The Trauma of Birth.  Rank argued that the anxiety that we experience is the result of the trauma of being expelled from our mother’s womb.  He argued that this was our first – and most significant – rejection. Even Freud was initially supportive of this theory.   But think about it – how would we be able to prove that this was not correct?  We would have to find someone who had “never been born” and test his or her mental health. In other words, there is no way of testing this theory.  There are several other theories that are not really testable.  Although these theories are often “accepted,” they are done so more as an act of belief than science.

The second characteristic of a good theory is that it has empirical support.  Empirical support may be in the form of an experiment, observations, interviews, or case studies.  But empirical support must be replicated in order for the theory to be well supported.  Conducting a single study that cannot be replicated, is not good support for a theory.  It is sometimes the problem in psychology that the results of a study are not replicated when different samples are used.

The third characteristic of a good theory is that it can be applied in many practical ways.  You will see that some theories have a lot of applications – or what we call high heuristic validity.  For example, you will see that a theory called “Social Identity Theory” can be applied to explain inter-group conflict, the origins of sexuality, one’s likelihood of supporting a charity and conformity to a group – as well as improve evacuation procedures in a disaster, reduce football hooliganism or changing one’s buying behavior. 

Another characteristic of a good theory is that its concepts are well defined and can be measured.  As you see in Bandura’s theory above, we have to be able to measure self-efficacy. How does one do that?  It is important that a test is designed and that researchers agree that the test does what it claims to do.  There are many things that psychologists study that can be problematic when it comes to how we measure them – for example, stress, anxiety, love, level of trust, self-efficacy, or intelligence.

It is also important that a theory not be biased.  There are several types of bias that a theory may have.  First, the research could be primarily done on students.  This means that we do not have good data on a range of ages.  In addition, studies may be biased to one gender, western culture, or a certain class of people.  Theories can also be biased because of the goals of the researcher – whether that be that the origin of depression is biochemical, as proposed by a drug company – or that homosexuality is purely genetic – as proposed by a gay rights activist.  This does not mean that the theory may not in the end have strong support, but such bias should make us raise our eyebrows.  Finally, the theory should take into consideration other factors.  If a biological theory ignores environmental variables, then the theory has a bias toward reductionism – that is, describing a complex phenomenon in terms of simple explanations or singular variables.

Finally, a good theory predicts behaviour. Even good theories are not able to predict an individual’s behaviour, but can predict trends within a population.

To remember what makes a good theory, you may want to use the following acronym:


Psychological theory in practice

As you begin your IB Diploma studies, here is a simple question: Do you believe in hard work or talent? Professor Carol Dweck from Stanford University in the USA has formulated a theory of the importance of people’s mindset in explaining success. Through systematic research, Dweck discovered that many talented people do not achieve their potential. She concluded that it is not talent or intelligence, as such, which is the key to understanding success. Rather, it is the way people explain things. She found that people tended to look at intelligence or talent as something that is either fixed or changeable. And those who saw intelligence as "fixed", were less likely to take risks and improve their learning.

According to Dweck’s theory, people with a fixed mindset believe that intelligence is static: because they want to appear smart; they avoid challenges, give up easily, and consider effort to be a waste of time. They tend to ignore useful negative feedback and feel threatened by the success of others. The consequence for these people is that often they do not achieve their full potential.

In contrast, people with a growth mindset believe that intelligence is not fixed: they think that it can be developed and therefore they do not mind challenges. They persist when they experience setbacks, consider effort to be part of the process of mastering something, learn from criticism, and find inspiration in the success of others. This approach reflects the belief that you can change things if you want to.

In order to test this theory, Dweck and Blackwell (2007) carried out an experiment with low-achieving students aged 12–13 years (seventh-graders). All students were given an introduction to the brain and study skills. Half of them also attended a neutral session on memory, while the other half attended a lecture on how intelligence can be developed through exercise - just as you can train your physical body. The result was that the students who were trained to adopt a growth mindset about intelligence were much more motivated, and this was demonstrated in their maths grades. Students in the group that did not attend the intelligence lecture showed no improvement, despite all the other interventions. According to Dweck, telling students that intelligence can be developed can have an incredible impact on their motivation to learn.

ATL:  Thinking about research

Dweck’s theory of motivation predicts that people who attribute their failures to lack of ability become discouraged even in areas where they are capable. Those who think they simply have not tried hard enough are encouraged to try harder when they experience setbacks.

1.  Does this theory correspond to real life? Try to evaluate the theory using some of your own experiences.

2.  To what extent could this theory be applied to different areas of human behavior – for example, exercise and health behaviour, sports, or the arts?  

3.  Do you think that this theory could be biased in any way?

ATL:  Inquiry

How can you use research to improve real-life situations? The British Psychological Society’s Research Digest contains many brief descriptions of empirical studies in the psychology of education. You can find these studies here.

1. Find an empirical study on this site that interests you.

2. Write a brief summary of the study. State what the researcher was looking for, how the research was carried out, and what the findings were.

3. If you were the headmaster or principal of a school, what would research like this mean to you? Would you make any changes to improve the school you work in?

What do psychologists do?

Before we begin our formal study of psychology, it is important to know what psychologists actually do. The answer is – almost everything!  Since psychologists try to understand human behavior, psychologists can work in almost any field.  The following list contains just some examples of potential careers in psychology.

Aviation psychologists study the behaviour of pilots and flight crew, as well as how to improve airline safety.

Clinical psychologists assess, diagnose and treat individuals suffering from psychological distress and mental illness.

Cognitive psychologists investigate how people think, including topics such as decision-making and problem-solving.

Consumer psychologists research consumer behaviour and develop marketing strategies to promote businesses.

Developmental Psychologists research human development across the entire lifespan – from infancy to old age.

Educational psychologists study how people learn and develop instructional strategies and teaching techniques.

Forensic psychologists study the origins of criminal behaviour as well as how psychological research can be applied to improve the justice system.

Health psychologists conduct research on community health issues. They also seek to educate the community and develop prevention programs.

Industrial-Organizational psychologists study workplace behaviour such as how to select the best employees for particular jobs and how to increase worker productivity.

Military psychologists apply psychological theory to improve the military – for example, treating soldiers suffering from mental illness or emotional distress, researching different aspects of military life, and helping soldiers transition back to civilian life.

Sports psychologists study how psychological factors affect performance and how participation in sport and exercise affect psychological and physical factors.

Checking for understanding

Prejudice is an example of a(n)...


Which of the following is not a characteristic of a good theory?

Several theories are reductionist, but a theory may also be more holistic.  This is true of many sociocultural theories. Although reductionism is not necessarily a good or bad characteristic of a theory, it is not a requirement for a "good theory."


What is the name given to data that is based on personal experience?

Empirical data is obtained through systematic and controlled research.  There is no such thing as heuristc data.


According to Carol Dweck's theory, students who have a fixed mindset ...

Dweck argued that those who have a fixed mindset believe that their skills are a "talent."  Therefore, they do not take risks because failure would hurt their identity.


Which type of psychologist would most likely study the extent to which we can trust eyewitness testimony of children in domestic abuse trials?



Which type of psychologist would most likely study strategies for getting people to stop drinking high-caffeine drinks?



Which type of psychologist would most likely study the effects of poverty on brain development?



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Fundamentals of research

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