In everyday life, when people use words like abnormal or mad, they usually mean that a person’s behavior, thoughts, or emotions seem unusual, unacceptable, or difficult to understand compared to what society considers normal. These terms are often used loosely and emotionally, based on personal opinions and social expectations. In psychology, however, these words have a more specific meaning. They refer to patterns of behavior or mental functioning that deviate from social norms, cause distress, interfere with daily functioning, or may create danger to the person or others. Even then, abnormality is not a fixed label; it is a complex and relative concept.


The concept of abnormality is also difficult to define. Abnormal behavior can be very different from person to person. So, even though some definitions may seem simple and clear, but it leads to confusion when applied in real life. The psychological abnormality is the scientific study of abnormal behavior undertaken to describe, explain, predict, and change abnormal patterns of functioning.

Most of the proposed definitions have some features in common, often called “the four Ds”: Deviance, Distress, Dysfunction, Danger.

Which means, the pattern of psychological abnormality is typically deviant (different, unusual, extreme, bizarre), distressing (unpleasant and upsetting to the person), dysfunctional (interfere with daily activity, unable to do normal functioning), and possibly dangerous to self or others.

Though these features give a better understanding of psychological abnormality, it has many limitations and difficulties.

1. Deviance

Abnormal psychological functioning is deviant from cultural norms. Norms are stated and unstated rules for proper conduct. Behavior that breaks legal norms is considered to be criminal. Behavior thoughts and emotions that break norms of psychological functioning are called abnormal.

For example, if someone came to a funeral wearing bright party clothes, laughing and dancing, it would violate the cultural norms and be considered abnormal. A society’s norms grow from its culture.

But judgement about abnormality is based on not only cultural norms but also specific circumstances. For example, at the time of disasters, war or illness, extreme reactions might look abnormal but can be normal response. So, it sometimes depends on the situations.

2. Distress

Distress means that the person’s behavior, thoughts, or emotions cause them to suffer. But it is not always present in abnormality and not all distress indicates abnormality.

For example, some people may experience hallucination without feeling distress and even enjoying them. Some people swim in the freezing lake and enjoy it even though it seems distressed.

3. Dysfunctional

Abnormal behavior is dysfunctional because it interferes with daily functioning, makes making it difficult to work productively, maintain relationships, care for one’s self.

For example, quit job, leave family, withdraw from social life. But dysfunction alone does not always indicate abnormality. For example, Gandhi fast for political protest, which is seen as normal.

4. Danger

Psychological dysfunctioning behavior is dangerous to oneself and other. This kind of person may harm themselves or people around him. Although danger is considered as a feature of abnormal psychological functioning, most people with abnormality are not dangerous.

The definition of abnormality is further complicated by society’s role. Sometimes, behavior meets all four Ds, but people ignore that because they are common in their subculture. Smoking, drinking in college.

One clinical theorist, Thomas Szasz (1920–2012), argued that mental illness is a myth created by society to control people with unusual pattern of living. According to him, many behaviors labelled as “abnormal” are simply problems in living, not signs of illness. For example, hearing voice may be seen as a symptom of a mental disorder, but in many subculture it is viewed as a spiritual gift or communication with ancestors, and is not considered abnormal at all.

Abnormal or unusual behaviors sometimes seen as eccentric. Eccentric as a person who deviates from common behavior patterns or displays odd or whimsical behavior. Researcher David Weeks studied 1000 eccentrics and identified 15 characteristics. Characteristics of eccentric people include non-conformity, creativity, strong curiosity, idealism, extreme interest and hobbies, lifelong awareness of being different, high intelligence, unusual eating and living habits, non-marriage, oldest from only son, and poor spelling skills.

According to Weeks, they do not typically suffer from mental illness. Eccentricity is chosen freely and gives pleasure. It does not make the person dysfunctional and have fewer emotional problems than the general population.

Even if we accept psychological abnormality as a valid concept, applying its definition is very difficult. In different places in the world, the cultural norms are different, so one culture accepts the deviant or dysfunctional behavior but other does not. Situation also matters here. A behavior might be accepted in one situation but not in other. The four D criteria are often vague and subjective. Besides, professionals often disagree about definitions because psychology has multiple school of thoughts such as biological, psychodynamic, humanistic, and cognitive-behavioral. This leads to inconsistent judgement on same case.

So, because of these challenges and limitations, many definitions of abnormality have been proposed over year but none has won total acceptance.