My name is Sam Vaknin, and I am the author of Malignant Self-Love, Narcissism Revisited.

Psychosis is chaotic thinking that is a result of severely impaired reality tests. The patient cannot tell inner fantasy from outside reality.

Some psychotic states are short-lived and transient, they call them micro-episodes. These last from a few hours to a few days, and are sometimes reactions to stress.

Psychotic micro-episodes are common in certain personality disorders, most notably in borderline and schizotypal personality disorders, but also in narcissistic personality disorders.

Persistent psychosis are a fixture of the patient’s mental life and manifest for months or years. These are not micro-episodes, these are full-fledged diseases.

Psychotics are fully aware of events and people out there. They cannot, however, separate data and experiences originating in the outside world from information generated by internal mental processes. The inside and the outside blur into one. They confuse the external universe with their inner emotions, cognitions, preconceptions, fears, expectations and representations.

Similarly, patients suffering from narcissistic personality disorder, to a lesser extent antisocial and histrionic personality disorders, fail to grasp other people as full-fledged entities. They regard even their nearest and dearest as kind of cardboard cut-outs, two-dimensional representations, intrograms or symbols. They treat people as instruments of gratification, functional automata or extensions of themselves.

To them, people are functions, near functions, nothing else.

Consequently, both psychotics and people with personality disorders have a distorted view of reality, and they are not rational. No amount of objective evidence can cause these people to doubt or reject their hypotheses and convictions. We call it confirmation bias.

Full-fledged psychosis involves conflicts and even bizarre delusions and the unwillingness to confront and consider contrary data or information.

Psychotics are preoccupied with a subjective rather than with the objective. Thought becomes utterly disorganized and fantastic. There is a thin line separating nonpsychotic from psychotic perception and ideation.

On this spectrum, we also find the schizotypal and the paranoid personality disorder.

The Diagnostic and Statistical Manual defines psychosis as restricted to delusions or prominent hallucinations, with the hallucinations occurring in the absence of insight into the pathological nature.

So what are delusions? What are hallucinations? And in which way are they distinct?

A delusion is a false belief based on incorrect inference about external reality that is firmly sustained despite what almost everyone else believes and despite what constitutes incontrovertible and obvious proof of evidence to the contrary.

So delusions are entrenched and very hard to eradicate. A hallucination is merely a sensory perception that has a compelling sense of reality of a true perception but that occurs without external stimulation of the relevant sensory organs.

A delusion is therefore a belief, an idea or conviction firmly held despite abundant information to the contrary. The partial or complete loss of reality test is the first indication of a psychotic state or episode.

Beliefs, ideas or convictions shared by other people, members of the same collective, are not strictly speaking delusions although they may be hallmarks of what we call a shared psychosis, a mass psychosis.

There are many types of delusions. There are paranoid delusions.

Paranoid delusion is the belief that one is being controlled or persecuted by stealth powers and conspiracies. This is common in the paranoid, antisocial, narcissistic, borderline, avoidant and dependent personality disorders.

Then we have the grandiose magical delusions, the conviction that one is important, omnipotent, omniscient, possessed of occult powers or is a historical figure. This kind of megalomania as it used to be called in the 19th century is typical of narcissists.

Invariably harbor such delusions.

Then we have referential delusions, formerly known as ideas of reference. That is the belief that external, objective events carry hidden or coded messages or that one is the subject of discussion, dissection, derision or opprobrium even by total strangers.

This is common in the avoidant, schizoid, schizotypal, narcissistic and borderline personality disorders.

Again, hallucinations are not delusions. Hallucinations are fast perceptions based on false sensory input, not triggered by any external event or entity.

The patient is usually not psychotic. The patient with hallucinations is not psychotic. He is aware that what he sees, smells, feels or hears, is not there.

Still, some psychotic states are accompanied by hallucinations.

In the famous case of formication, feeling that bugs are crawling over or under one’s skin. That’s an example of a hallucination which accompanies psychotic states.

Similarly, there are a few classes of hallucinations.

We have auditory hallucinations, the false perception of voices and sounds such as buzzing, humming, rage of transmissions, whispering, motor noises and so on.

We have gustatory hallucinations, the false perception of tastes. We have olfactory hallucinations, the false perception of smells and sounds, burning flesh, candles.

Somatic hallucinations, the false perception of processes and events that are happening inside the body or to the body.

For instance, piercing objects, electricity running through one’s extremities.

Somatic hallucinations are usually supported by an appropriate and relevant delusional content.

We have tactile hallucinations, the false sensation of being touched or crawled upon or that events and processes are taking place under one’s skin.

This is usually supported by an appropriate and relevant delusional content as well.

Then we have visual hallucinations.

They are most common. The false perception of objects, people or events in broad daylight or in an illuminated environment with eyes wide open.

Hypnagogic and hypnopompic hallucinations are images, trains of events, experience while falling asleep or when waking up.

No hallucinations, these are not hallucinations in the strict sense of the word, but they are closed.

Hallucinations are common in schizophrenia, affective disorders and mental health disorders with organic origins. Hallucinations are also common in drug and alcohol withdrawal and among substance abuse, but they are not common among people with personality as well.