Paranoia (Delusional Disorder): A Definition, Symptoms And Treatment

Here we explain exactly what paranoia is, what causes paranoid thoughts, and how to treat them.

A definition of paranoia and its symptoms
A definition of paranoia and its symptoms

Paranoia is a term used to refer to those that experience irrational feelings of suspicion and mistrust. However, recently, the meaning of this word has become quite controversial.

Traditionally paranoia was associated with madness or the mentally disturbed -however, in this article, we're going to take a closer look at different aspects of this mental condition. With this goal in mind, we'll share the best definitions of this delusional disorder and the symptoms and causes of this mental state based on psychology.

Paranoia: Oxford Dictionary definition

First, before we dive into diagnostic manuals like the CIE-10 or the DSM-5, to define paranoia according to official mental health standards, we'll take a look at Oxford Dictionary's definition of this disorder.

According to the Oxford Dictionary, the term paranoia refers to, "a mental condition characterized by delusions of persecution,  unwarranted jealousy, or exaggerated self-importance." Besides, this dictionary states that this word originates from modern Latin and Greek from paranoos which means distracted which comes from para 'irregular' and noos 'mind.' As you can see, this still leaves a lot to the imagination when it comes to the meaning of this delusional disorder.

So, to reach a better understanding of this concept, we'll dive into diagnostic manuals and the works of well-known authors. Keep in mind that the idea of paranoia exists in many different branches of psychology, which is why it takes on a wide variety of meanings depending on which perspective you look at it from.

A psychological definition

In clinical psychology, using diagnostic manuals is common since it's the best way to give a group of symptoms a common name and ease the transmission of information to all professionals in the field.

The two most widely used manuals are the International Classification of Diseases (CIE-10), created by the World Health Organization, and the Diagnostic Manual of Mental Disorders (DSM-5), published by the American Psychological Association.

Currently, the term paranoia doesn't appear in either of these manuals  since the concepts "delusion" and "delusional disorder" replace it. With this in mind, we're going to analyze the CIE-10 to find out more about delusional disorders and where paranoia comes into play here.


Delusional disorders found in F22.0 of the CIE-10 states that this is a group of disorders where the affected person persistently has one or more delusions focused on a single topic. The theme of these ideas is unchanging -they don't have to be particularly strange or outlandish- but they can vary greatly.

Some of these delusions include having a stalker, jealousy, physical symptoms, others falling in love with them (erotomania), delusions of greatness, etc. These ideas cannot be connected to other more serious psychopathologies, thus ruling out possible schizophrenia and other psychotic disorders.

Paranoid thoughts can stick with a person for their entire life, and the onset usually occurs in adulthood or old age. These thoughts could be related to everyday situations, which is why they often don't even seem strange at all.

All other cognitive functions remain intact, including language and executive functions, although low-intensity emotional problems such as mild depression could appear. Of course, everyone is different, and in some cases, it is possible for these symptoms to emerge in conjunction with paranoia.

For a case of delusional disorder to be diagnosed, paranoia must last for at least 3 months and not be dependant on cultural factors. Also, as we stated beforehand, this symptom can't appear along with other psychotic symptoms such as hallucinations, since this would point more towards a schizophrenia diagnosis.

Paranoia symptoms are both physical and psychological.
Paranoia symptoms are both physical and psychological.

Causes of paranoia

Although there is a general consensus among all mental health professionals currently regarding the meaning of paranoid thoughts, there are still some deviations when it comes to the origins of this disorder. So, below we'll take a look at these factors to get a more complete understanding of the term.

Besides, the term paranoia has gone through massive changes throughout psychology's history. This concept was introduced by psychiatry and studied by hundreds of authors, and of course, each and every one of them gave this word a different meaning due to fluctuations in the word and the inherent creativity of language.

Psychodynamic perspective (psychoanalysis)

According to the famous Jacques Lacan, paranoia is a form of psychosis characterized by self-referential delusions where the individual accuses another person, object, or entity of causing their discomfort. This all occurs through a process called projection, a psychological defense mechanism. 

This idea is quite solid and difficult to rule out, although people provide undeniable evidence that this theory is wrong. Lacan studied this disorder while working on his doctoral thesis focusing on a patient he calls Aimée -which led to his discovery of self-punishment paranoia.

An underlying desire for punishment exists in this type of paranoia, according to Lacan, and for this to happen, those affected act in a way that makes this punishment possible. In short, this is related to feelings of guilt.

Paranoia is also known as delusional disorder in psychology.
Paranoia is also known as a delusional disorder in psychology.


Cognitive-behavioral model

Based on this approach, paranoid thoughts come from the cognitive interpretation that each person synthesizes based on their own experiences and personal beliefs.

This is why  psychologists propose using cognitive restructuring (composed of discussion and behavior tests) to modify the interpretation of specific information, thus reducing the strength and conviction of delusions until the patient starts to question these ideas themselves. 

The humanistic viewpoint

Coming from the humanistic perspective, promoted by recognized authors like Abraham Maslow and Carl Rogers, the root of all paranoid thoughts is low self-esteem. Feelings like vulnerability also lead people to commit self-deception which involves anticipating or protecting themselves from feared situations.

People that have paranoid thoughts mention anticipation ("at least I saw it coming") in situations that they are extremely fearful of, although, in reality, there may not even be any real reason for this situation to happen. So, in this theory, as self-esteem increases, these fears diminish.

Gestalt psychology

Jean Marie Delacroix (2008) stated that "psychosis is not a sign of madness, but instead liberation of the self in search of creative adjustment." In spite of this, some paranoid thoughts are widespread as irrational belief systems that interfere in people's daily lives.

These ideas are interpreted by Gestalt mental health professionals as projections onto others in their environment or their negative self that generate anxiety and discomfort in the individual. They try to unleash these paranoid thoughts to diminish them. Of course, this type of method is rebuked by psychologists from other branches.


Delacroix, J. M. (2008). Psychotherapy encounter. An anthropological perspective on the relationship and meaning of illness in the paradox of life. Santiago, Chile: Cuatro Vientos.

Oxford Dictionary (2018). Oxford Living Dictionaries: English. Available at

World Health Organization (1992).Tenth revision of the International Classification of Diseases (CIE-10). Mental and behavioral disorders. Clinical descriptions and diagnostic guidelines. Madrid: Méditor.