Psychosis and Schizophrenia General

Question 1

In a study of the disabling effects of different health conditions in 14 countries, what was ranked 3rd most severe?

Answer 1

Active psychosis

Question 2

What causes psychosis?

Answer 2

Psychosis is a set of symptoms and not a disease in itself. It can have a large number of causes.
Pathological causes include: schizophrenia, bipolar, drugs (recreational and prescription), PTSD, sleep deprivation, Alzheimer’s

Question 3

Positive symptoms of schizophrenia

Answer 3

Delusions, hallucinations, catatonia, disordered thoughts, stereotyped movements
At least one of these has to occur for classification of a psychotic episode

Question 4

Negative symptoms of schizophrenia

Answer 4

Loss of emotional response, anhedonia, lack of motivation, cognitive deficits
These are the chronic, prodromal, and residual symptoms, and are the most difficult to manage

Question 5

Epidemiology of schizophrenia

Answer 5

Around 1% of the population
1.4 males to 1 females
Strikes males in late teens and females in early twenties

Question 6

Historical therapies for schizophrenia

Answer 6

Insulin shock therapy
ECT
Fever therapy

Question 7

Schizophrenia is likely to be…

Answer 7

…several related disorders

Question 8

What is schizotypal disorder?

Answer 8

Considered to be a milder form of schizophrenia as many patients do not have overtly psychotic symptoms, affects 2-3% of the population

Question 9

The functional neuroanatomy of hallucinations in schizophrenia

Answer 9

Basal ganglia project to (frontal, parietal and temporal lobes) the frontal and inferotemporal cortex
Output nuclei of the BG project to the inferotemporal cortex via the thalamus (inferotemporal input to and output from BG) –> BG influences higher order processing
L-DOPA hallucinations due to excessive stimulation of DA-Rs in visual striatum –> increased activity in nucleus reticulata –> increases in thalamic input to the inferotemporal cortex

Question 10

Proposed loop between the basal ganglia and the inferotemporal cortex

Answer 10

inferotemporal cortex –> putamen –> caudate nucleus –> substantia nigra pars reticulata –> ventral anterior magnocellular division of the thalamus –> inferotemporal cortex

Question 11

Approximately how much does schizophrenia cost the US per year?

Answer 11

Around 2.5% of total annual US health expenditure

Question 12

Prodromal signs of schizophrenia

Answer 12

Predeeding a psychotic episode
Include social isolation and withdrawal, inability to carry out expected roles, odd behaviour and ideas, neglect of personal hygiene and blunted affect

Question 13

Residual symptoms

Answer 13

Usually the negative aspects: socially isolated, flat affect, poverty of speech, attention and motivation

Question 14

What are the three most readily distinguished subtypes of schizophrenia

Answer 14

Paranoid- delusions of persecution
Disordered- diverse symptoms and profound deterioration of personality
Catatonic- a rare form in which mutism and abnormal postures predominate

Question 15

2 views on the positive and negative symptoms of schizophrenia

Answer 15

Either different phases of the same disease in which the negative symptoms reflect the long-term outcome of positive symptoms OR two distinct courses and underlying pathologies

Question 16

Concordance for schizophrenia

Answer 16

45% in monozygotic twins, 15% in dizygotic (about the same as other siblings)

Question 17

Importance of the mesocortical pathway in schizophrenia

Answer 17

Important for the negative symptoms

Symptoms resemble effects of surgical disconnection of the frontal lobes

Question 18

Lesion of the VTA (which give rise to DAergic mesolimbic system)…

Answer 18

Cause dementia and psychotic symptoms

Question 19

Experimental evidence for the interaction between the mesocortical and mesolimbic pathways

Answer 19

Chemical lesioning of the mesocortical pathways in experimental animals enhances the synaptic responsiveness in the mesolimbic pathways, specifically in its terminations in the nucleus accumbens

Question 20

Importance of the mesolimbic pathway in schizophrenia

Answer 20

Positive symptoms

Question 21

Weinberger proposes that…

Answer 21

…activity in the mesocortical pathway normally inhibits the mesolimbic pathway by way of feedback inhibition, and that the primary defect in schizophrenia is a reduction in this thus leading to disinhibition and overactivity of the mesolimbic system