MPBD: Schizophrenia
Symptoms of schizophrenia • Dysfunction of motivation: reduced motivation
The symptoms are categorized into 3 groups, persistence, passivity, reduced ability to
positive (present), negative (absent), and undertake and complete everyday tasks, and
cognitive symptoms. they may have poor personal hygiene
• Anhedonia: dysfunction of the capacity of
Positive symptoms pleasure: reduced ability to experience pleasure,
Positive symptoms are excess of normal decreased interest in previous hobbies
functions and include psychosis (delusions, • Asociality: reduced social drive and
hallucinations), disorganized speech, interaction; little sexual interest, few friends,
distortions/exaggerations in language and little interest in spending time with friends
communication, disorganized behaviour, and • Executive dysfunction: problems with
agitation. planning, maintaining goals, problem-solving,
and prioritizing (depending on the good
Delusions functioning of the prefrontal cortex)
Delusions are misinterpretations of perception
or experience and are part of psychosis. Kinds Etiology of schizophrenia
of delusions are paranoid delusions where the The symptoms of schizophrenia arise because of
person thinks that they are being watched or malfunctioning brain circuits.
that someone wants to murder them. They
could also have referential delusions where
the person thinks that something refers to
oneself, a secret message especially for them,
such as a message on tv. Another type of
delusion is the grandiose delusion where the
person thinks that one is a powerful person.
Some people could also have religious
delusions where they think they are jezus or
another divine being. People also could have
the delusion that they are poisoned, have
sexual delusions and think they are The positive symptoms are linked to the
irresistible (mostly seen in manic depressive mesolimbic system (dopamine system), and the
persons), leaky mind delusions where they negative and cognitive symptoms are linked to
think people can read their mind, and lastly the prefrontal cortex.
people could have thoughts that are not their
own, but are transplanted into the brain by for Dopamine has long played a prominent role in
example aliens. the hypothesis of schizophrenia. Cocaine and
amphetamine are drugs that could induce
Hallucinations psychosis. They block the dopamine transporter
The most common are auditory hallucinations since they are dopamine reuptake inhibitors.
where harsh voices give negative comments/ Because of this, they thought that dopamine
orders. Hallucinations could therefore occur in plays a role in schizophrenia. This was supported
any sensory modality such as, visual (seeing by the effect of antipsychotics, which are
things), tactile (feeling something on your dopamine antagonists/dopamine receptor
skin), gustatory (taste), and olfactory (smell blockers.
of gas or rotting meat). These hallucinations
are also present in psychosis. Dopamine hypothesis
There are several dopamine pathways.
Negative symptoms A) Nirgostriatal
These are reductions in normal functions, B) Mesolimbic
such as: C) Mesocortical
• Blunted affect: restrictions in range and D) Tuberoinfundibular
intensity of emotional expression (feeling
empty, recalling few emotional experiences,
little facial expression).
Symptoms of schizophrenia • Dysfunction of motivation: reduced motivation
The symptoms are categorized into 3 groups, persistence, passivity, reduced ability to
positive (present), negative (absent), and undertake and complete everyday tasks, and
cognitive symptoms. they may have poor personal hygiene
• Anhedonia: dysfunction of the capacity of
Positive symptoms pleasure: reduced ability to experience pleasure,
Positive symptoms are excess of normal decreased interest in previous hobbies
functions and include psychosis (delusions, • Asociality: reduced social drive and
hallucinations), disorganized speech, interaction; little sexual interest, few friends,
distortions/exaggerations in language and little interest in spending time with friends
communication, disorganized behaviour, and • Executive dysfunction: problems with
agitation. planning, maintaining goals, problem-solving,
and prioritizing (depending on the good
Delusions functioning of the prefrontal cortex)
Delusions are misinterpretations of perception
or experience and are part of psychosis. Kinds Etiology of schizophrenia
of delusions are paranoid delusions where the The symptoms of schizophrenia arise because of
person thinks that they are being watched or malfunctioning brain circuits.
that someone wants to murder them. They
could also have referential delusions where
the person thinks that something refers to
oneself, a secret message especially for them,
such as a message on tv. Another type of
delusion is the grandiose delusion where the
person thinks that one is a powerful person.
Some people could also have religious
delusions where they think they are jezus or
another divine being. People also could have
the delusion that they are poisoned, have
sexual delusions and think they are The positive symptoms are linked to the
irresistible (mostly seen in manic depressive mesolimbic system (dopamine system), and the
persons), leaky mind delusions where they negative and cognitive symptoms are linked to
think people can read their mind, and lastly the prefrontal cortex.
people could have thoughts that are not their
own, but are transplanted into the brain by for Dopamine has long played a prominent role in
example aliens. the hypothesis of schizophrenia. Cocaine and
amphetamine are drugs that could induce
Hallucinations psychosis. They block the dopamine transporter
The most common are auditory hallucinations since they are dopamine reuptake inhibitors.
where harsh voices give negative comments/ Because of this, they thought that dopamine
orders. Hallucinations could therefore occur in plays a role in schizophrenia. This was supported
any sensory modality such as, visual (seeing by the effect of antipsychotics, which are
things), tactile (feeling something on your dopamine antagonists/dopamine receptor
skin), gustatory (taste), and olfactory (smell blockers.
of gas or rotting meat). These hallucinations
are also present in psychosis. Dopamine hypothesis
There are several dopamine pathways.
Negative symptoms A) Nirgostriatal
These are reductions in normal functions, B) Mesolimbic
such as: C) Mesocortical
• Blunted affect: restrictions in range and D) Tuberoinfundibular
intensity of emotional expression (feeling
empty, recalling few emotional experiences,
little facial expression).
