12. Psychosis Flashcards Preview

ESA 4- Nervous system > 12. Psychosis > Flashcards

Flashcards in 12. Psychosis Deck (8):
1

What is "psychosis"? How can it be caused?

Presence of hallucinations or delusions (i.e. symptoms, not diagnosis) - multiple causes, e.g.
- delirium caused by infection
- acute drug/alcohol intoxication
- hyperthyroidism
- encephalitis
- medications, e.g. steroids, L-dopa

2

What is a hallucination? What is a delusion?

Hallucination = perception without a stimulus, can be in any sensory modality

Delusion = unshakeable abnormal belief, outside of cultural norms

3

Describe the 5 1st rank symptoms of schizophrenia.

1. AUDITORY HALLUCINATIONS, e.g.
- thought echo (hearing thoughts aloud)
- running commentary (voices referring to P in 3rd person and conversing with each other about the P)

2. PASSIVITY EXPERIENCES: P believes an action or feeling is caused by an external force (e.g. MI5)

3. THOUGHT WITHDRAWAL: thoughts are being taken out of mind, e.g.
- thought broadcast (thoughts being made known to others, e.g. via radio)
- thought insertion (thoughts being implanted by others)

4. DELUSIONAL PERCEPTIONS: attribution of new meaning, usually in sense of self-reference, to a normally perceived object

5. SOMATIC HALLUCINATIONS: mimic feelings from inside the body (e.g. snake in abdomen)

4

What is the difference between positive and negative symptoms in schizophrenia?

Positive: added symptoms, e.g. delusions, hallucinations, thought disorder, lack on insight

Negative: take away from P, e.g. low motivation, social withdrawal, self-neglect

5

Describe the 5 types of schizophrenia.

1. PARANOID SCHIZOPHRENIA
- delusions or hallucinations prominent

2. HEBEPHRENIC SCHIZOPHRENIA
- weird, giggly, child-like
- definite and sustained flattening or shallowness of affect, or incongruity/inappropriateness or affect, aimless and disjointed behaviour or thought disorder affecting speech
- hallucinations/delusions must not dominate

3. SIMPLE SCHIZOPHRENIA
- loss of drive and interest, aimlessness, idleness, self-absorbed attitude and social withdrawal
- marked decline in social, academic or work performance
- no hallucinations/delusions

4. CATATONIC SCHIZOPHRENIA

5. UNDIFFERENTIATED SCHIZOPHRENIA
- insufficient symptoms to meet criteria of any subtype, or many symptoms fitting >1 criteria

6

Which NT is thought to be involved in schizophrenia? Explain how.

Dopamine pathways:

1. Mesocortical pathway - from ventral tegmental area to frontal cortex and cingulate gyrus. Thought to be underactive in SZP.

2. Mesolimbic pathway - from ventral tegmental area to limbic structures (amygdala, septal area and hippocampal formation). Thought to be overactive in SZP.

7

Describe the autoimmune hypothesis of SZP.

Based on anti-NMDA encephalitis: antibodies, e.g. after viral infection or ovarian teratoma, bind to NMDA receptor causing internalisation and hypofunction

8

Describe the medications used in SZP management.

Act to regulate dopamine:

1. typical antipsychotics (e.g. chlorpromazine) - block D2 Rs in all CNS dopamineric pathways, mainly mesolimbic and mesocortical but others areas also so many side effects

2. atypical antipsychotics (e.g. haloperidol) - lower affinity for D2 Rs so milder side effects