Schizophrenia and related disorders lecture Flashcards
• Be able to differentiate psychosis and schizophrenia • Identify the basic symptoms of schizophrenia • Outline the diagnostic categories of psychotic conditions • Be able to create a basic management plan for a patient with schizophrenia • Be aware of delusional disorders
Definition of hallucination
A perception which occurs in the absence of a stimulus. To the person this has the impact of a real perception and is indistinguishable. It occurs externally (not in the mind).
illusion definiton
False perception of a real stimulus. Three types: affect, completion and pareidolia.
Illusion vs hallucination
An illusion is based on a real sensory stimulus that is interpreted incorrectly whereas a hallucination is created by the mind without any stimulus.
What are the 3 main types of illusions?
Definition of positive symptoms
A cluster of psychotic symptoms including hallucinations and delusions.
Definition of negative symptoms
A cluster of symptoms that often occur in chronic schizophrenia including poverty of speech, flat affect, poor motivation, poor attention and neglect.
Negative symptoms vs positive symptoms
A positive symptom is something added on to what most people experience
(i.e. a hallucination)
whereas negative symptoms are the lack of a normal experience
(i.e. lacking concentration)
Definition of delusion of control/passivity
The subject believes their thoughts, feelings and/or actions are not their own but are being imposed/controlled by an outside force.
Remember in passivity experiences the subject is ‘passive’ as they believe they are being controlled by another agent.
Definition of ideas of reference
The belief that innocuous events have direct personal significance to the subject (e.g. believing something on the TV is a direct message to them).
Definition of thought broadcast
The subject believes their thoughts are being shared with others (e.g. being broadcast on the radio)
Ideas of reference vs thought broadcast
These can be easy to mix up. In thought broadcast they believe their thoughts are being broadcast for others to receive. With ideas of reference they take special meanings from inanimate stimuli.
Definition of psychosis
List of some of conditions that cause psychosis
There are three clusters of psychotic symptoms:
- hallucinations
- delusions
- thought disorders
What is a hallucination?
what is a delusion?
A false, unshakable belief held with intense conviction
Held despite evidence to the contrary
Not a belief held by others in the same culture
- What is a thought disorder?
Definition of schizophrenia
This references the splitting of the mind from reality and not a split personality.
Schizophrenia is a specific diagnosis
Epidemiology of schizophrenia
More common in men
Earlier onset in men:
Male average onset 20 to 28 years
Female average onset 26 to 32 years
Incidence 0.1 %
Prevalence 0.5 to 1%
Aetiology of schizophrenia
More common in urban areas
Higher rates in those who have moved to the UK than in the UK itself or in their country of origin
More common with economic adversity/social exclusion
Higher rates in those who have experienced childhood trauma or abuse
Strong genetic links but no clear direct inheritance pattern so there must be multiple implicated genes
50% risk if both parents have schizophrenia
50% monozygotic twin concordance
Cannabis
Four times the risk if regular use before age 15
More common in winter births or if perinatal viral infections or trauma
Main Pathophysiology in schizophrenia
Dopamine is the most implicated neurotransmitter in schizophrenia
We know this as antipsychotics are dopamine antagonists and SPECT scans show increase DA receptor occupancy in patients with schizophrenia
how each of the DA pathways are affected in schizophrenia
example of main neurotransmitters
positive symptoms vs negative symptoms and some features of each
