Textbook of psychiatry
H5 Psychosis Spectrum Disorders
Psychosis spectrum disorders are generally characterised by one or more of the following
symptoms: delusions, hallucinations and disorganized speech or behaviour.
Classification of psychosis spectrum disorders (DSM-5):
Schizophrenia
Schizophreniform disorder
Schizoaffective disorder
Delusional disorder
Brief psychotic disorder
Catatonia
Substance/medication-induced psychotic disorder
Psychotic disorder due to another medical condition
Schizophrenia:
Schizophrenia usually manifests between the ages of 16 and 30. Symptoms are classified into
positive, negative and cognitive symptoms. The disorder usually begins with negative
symptoms; positive symptoms sometimes take years to develop. Long-standing severe
negative symptoms are associated with a poor prognosis.
Positive symptoms
o Symptoms of impaired sense of reality
Hallucinations (hearing voices!)
Delusions (loss of normal boundaries of mental function!)
o Symptoms that are a manifestation of cognitive disorganization
Formal thought disorders (illogical connections and incoherence)
Negative symptoms
The absence of or a reduction in psychological manifestations that would normally be
present.
o Affective blunting (reduced/absent emotional reactions)
o Avolition (reduction in independent motor activity and actions)
o Apathy (lack of curiosity and affective motivation to act)
o Poverty of thought (experiencing few thoughts)
o Alogia or poverty of speech (speech is confined to what is absolutely
necessary)
o Anergia (lack of physical energy)
o Social withdrawal behaviour
o Self-care and other tasks are performed less well
Negative symptoms are sometimes caused partly by antipsychotics. Sometimes they
are due to lack of stimulation. These ‘secondary’ negative symptoms can be
alleviated by eliminating the cause.
, A lot of patients lack illness awareness. They do not seem to notice even severe
dysfunction; apparently, they do not find it distressing and therefore see no need for
treatment.
Cognitive symptoms
o Slowed information processing
o Disorders of attention and working memory
o Impaired verbal and visual memory
o Executive function disorders affects reasoning and problem solving
Furthermore, emotional utterances may be inconsistent with the situation (e.g. a patient
may laugh while talking about something sad) inappropriate affect.
Criteria for schizophrenia:
A) 2 or more of the following (at least one must be a, b or c):
a. Delusions
b. Hallucinations
c. Disorganized speech
d. Grossly disorganized or catatonic behaviour
e. Negative symptoms
B) For a significant portion of time, the level of functioning in one or more important
major areas (work, relations, self-care, etc.) must be diminished.
C) Continuous signs of the disturbance persist for at least 6 months with at least 1
month of symptoms that meet criterion A
Schizophreniform disorder:
Classification criteria are largely similar to those for schizophrenia:
Schizophrenia symptoms > 6 months
Schizophreniform disorder symptoms >1 month, but < 6 months
Functioning returns once the symptoms of the disorder have cleared up. Positive prognostic
features are:
Acute onset (withing 4 weeks of the first change in functioning)
Confusion or perplexity at the peak of the psychotic episode
Good premorbid functioning
Absence of flat affect
Criteria for schizophreniform disorder:
A) Meets criterion A for schizophrenia
B) >1 month, <6 months
H5 Psychosis Spectrum Disorders
Psychosis spectrum disorders are generally characterised by one or more of the following
symptoms: delusions, hallucinations and disorganized speech or behaviour.
Classification of psychosis spectrum disorders (DSM-5):
Schizophrenia
Schizophreniform disorder
Schizoaffective disorder
Delusional disorder
Brief psychotic disorder
Catatonia
Substance/medication-induced psychotic disorder
Psychotic disorder due to another medical condition
Schizophrenia:
Schizophrenia usually manifests between the ages of 16 and 30. Symptoms are classified into
positive, negative and cognitive symptoms. The disorder usually begins with negative
symptoms; positive symptoms sometimes take years to develop. Long-standing severe
negative symptoms are associated with a poor prognosis.
Positive symptoms
o Symptoms of impaired sense of reality
Hallucinations (hearing voices!)
Delusions (loss of normal boundaries of mental function!)
o Symptoms that are a manifestation of cognitive disorganization
Formal thought disorders (illogical connections and incoherence)
Negative symptoms
The absence of or a reduction in psychological manifestations that would normally be
present.
o Affective blunting (reduced/absent emotional reactions)
o Avolition (reduction in independent motor activity and actions)
o Apathy (lack of curiosity and affective motivation to act)
o Poverty of thought (experiencing few thoughts)
o Alogia or poverty of speech (speech is confined to what is absolutely
necessary)
o Anergia (lack of physical energy)
o Social withdrawal behaviour
o Self-care and other tasks are performed less well
Negative symptoms are sometimes caused partly by antipsychotics. Sometimes they
are due to lack of stimulation. These ‘secondary’ negative symptoms can be
alleviated by eliminating the cause.
, A lot of patients lack illness awareness. They do not seem to notice even severe
dysfunction; apparently, they do not find it distressing and therefore see no need for
treatment.
Cognitive symptoms
o Slowed information processing
o Disorders of attention and working memory
o Impaired verbal and visual memory
o Executive function disorders affects reasoning and problem solving
Furthermore, emotional utterances may be inconsistent with the situation (e.g. a patient
may laugh while talking about something sad) inappropriate affect.
Criteria for schizophrenia:
A) 2 or more of the following (at least one must be a, b or c):
a. Delusions
b. Hallucinations
c. Disorganized speech
d. Grossly disorganized or catatonic behaviour
e. Negative symptoms
B) For a significant portion of time, the level of functioning in one or more important
major areas (work, relations, self-care, etc.) must be diminished.
C) Continuous signs of the disturbance persist for at least 6 months with at least 1
month of symptoms that meet criterion A
Schizophreniform disorder:
Classification criteria are largely similar to those for schizophrenia:
Schizophrenia symptoms > 6 months
Schizophreniform disorder symptoms >1 month, but < 6 months
Functioning returns once the symptoms of the disorder have cleared up. Positive prognostic
features are:
Acute onset (withing 4 weeks of the first change in functioning)
Confusion or perplexity at the peak of the psychotic episode
Good premorbid functioning
Absence of flat affect
Criteria for schizophreniform disorder:
A) Meets criterion A for schizophrenia
B) >1 month, <6 months
