- [Voiceover] So people with delusions have
these unusual beliefs that are clearly false
but they hold firmly to this notion
that the belief is actually true.
Various mental disorders including schizophrenia
and schizoaffective disorder leave all patients
with delusions of some kind.
Although a lot of times, these patients will present
with other symptoms of psychosis like hallucinations.
Delusional disorder on the other hand,
is characterized by someone having
just persistent delusions.
Now every delusion someone has
can either be considered non-bizarre or bizarre.
In non-bizarre, delusions are plausible,
meaning that whatever their belief is,
is actually possible but it's incorrect.
An example of a non-bizarre delusion
could be thinking that you're
constantly being followed by someone or
thinking that you have an infection when you really don't.
A bizarre delusion is one that's clearly not possible.
A classic example would be thinking that someone
has removed all of your internal organs
without leaving any sign of it
or leaving a scar of some kind and really sticking to this.
It's clearly not possible if the organs are missing
without leaving some kind of trace of removal, right?
So delusional disorder involves a delusion of some kind
either bizarre or non-bizarre without any other
symptoms of psychosis like hallucinations,
disorganized thoughts and behavior,
or other mood disorder symptoms like mania or depression.
It's only delusions.
Now another big difference here between delusional disorder
and other psychotic disorders like schizophrenia
is that despite these delusions, the person is able
to otherwise function pretty normally
in many areas of their life, like socially
or in relationships, or at work.
Now there's this like whole list of sub-types of delusions
that are usually associated with either non-bizarre
or bizarre delusions though these sub-types
aren't always just in one or the other.
Now to kinda get started, delusions of control
are delusions that somebody's controlling their thoughts
or behavior like, for example,
thinking that they're being controlled by aliens
and these are usually bizarre as being controlled
by someone is considered not quite plausible.
Nihilistic delusions are these ideas around
the non-existence of themselves or of parts of themselves
or even the world so they might hold on to the belief
that meteorites are going to destroy the Earth
and that the world is actually ending.
And delusions of thought broadcasting
are where the patient thinks that their thoughts
are being broadcasted for everyone to listen to.
Delusions of thought withdrawal, on the other hand,
is thinking that some of your thoughts
have been taken out of your mind
and that you have no control over this.
And these are all really considered bizarre delusions
usually but they don't necessarily have to be.
In some of the other types of delusions
that are considered non-bizarre
and could potentially be possible are ones like
persecutory delusions which are actually the most common
type of delusions and these involve the theme
of someone being followed or cheated or conspired against.
An example of this could be thinking that the government's
following them because the government
incorrectly thinks that they're actually a spy.
Delusional jealousy or sometimes
called delusions of infidelity is this firm belief
that your spouse or significant other is having an affair.
Delusional guilt or sin is this belief that you're guilty
of some crime and you should be punished severely.
An example of this could be thinking
that they're responsible for some catastrophe
like a house fire or something when they clearly weren't.
Delusions of reference are thoughts that
some sort of remark or event or broadcast is directed
at them or has some sort of special significance
like thinking that the news anchor on television
is actually trying to communicate directly with them.
Somatic delusions are delusions that have to do
with bodily functions or physical appearance.
Usually something to do with their body
being diseased or changed in some way.
So it could be thinking that your body
is infested with parasites.
Erotomania is this delusion that another person,
usually like a celebrity, is in love with them.
Grandiose delusions are those where the person
exaggerates themselves and thinks
that they have these special talents or abilities.
And finally religious delusions are any delusions
with a spiritual aspect although it's important
to remember that beliefs that are in line
with the person's culture aren't considered delusions.
And furthermore, any of these delusions that have been
mentioned might be mixed with each other as well.
Ok, so just like many other types of mental disorders,
the cause of developing these delusions
is essentially unknown and research has been
pretty difficult because many people with
delusional disorder don't seek out treatment or diagnosis.
And also, because the definition
of delusional disorder has evolved over time.
Currently, though, from the Diagnostic and Statistical
Manual for Mental Disorders, the fifth edition or the DSM-5,
the following criteria are given
for our delusional disorder: the delusions must have been
present for longer than one month, and they aren't
accompanied by any other psychotic symptoms
like hallucinations, disorganized speech or movements
or negative symptoms like flat affect.
Also, functioning hasn't been affected except
where it relates to the particular delusion
like, for example, if you avoided opening your mail
because you thought the post office
was trying to poison you.
Finally, other causes of the delusions have been ruled out
like medical conditions or other psychiatric disorders.
As to the treatment, this can be challenging.
People with delusions often deny any problems
or that there is anything wrong with their beliefs.
So sometimes anti-psychotic medications might be prescribed
to reduce the delusions but also psychotherapy
can be a very effective treatment.
Finally the prognosis for delusional disorder is usually
pretty good considering that most of the delusions
don't significantly impair their daily life.
Some patients, though, might get more involved
with their delusions and could risk further disfunction
or risk harming themselves or others.