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Flashcards in Neurobiology of psychosis Deck (19)
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1
Q

What are the following associated with? :

  • reduced frontal lobe volume
  • reduced frontal lobe grey matter
  • enlarged lateral ventricle volume
A

Associated with a poor prognosis

2
Q

Schizophrenia is associated in changes of which matter in the brain?

A

Associated with changes in the grey matter

  • changes are widely distributed
  • changes are present early in the disease (and likely premorbidly)
  • Grey matter reductions due to reduced aborisation and not neuron loss
  • grey matter reductions likely PROGRESSIVE in the initial years of the illness
3
Q

Good way to image the drug?

A

Diffusion tensor imaging (DTI)

4
Q

What does fractional anisotropy mean? (in terms of diffusion tensor imaging)

A

Higher numbers mean healthy white matter tracts

(but higher FA correlates with psychotic symptom severity. Myelin abnormalities may be a cause of the anisotropy abnormalities)

5
Q

What does mean diffusivity mean? (in terms of diffusion tensor imaging)

A

Higher numbers mean LESS healthy white matter tracts

6
Q

Why is it not possible to diagnose schizophrenia by radiology?

A

Not possible because of abnormal variation i.e. the AVERAGE brain of a patient with schizophrenia is smaller than the AVERAGE brain in a healthy control (average etc blah blah)

7
Q

Factors in pregnancy which could lead to schizophrenia development of that baby?

A
  • 2nd trimester viral illness

- Obstetric problems: pre-eclampsia. fetal hypoxia, emergency caesarian section

8
Q

Dopamine and the brain

A

It is assumed that schizophrenia is related to overactivity of dopamine pathways

9
Q

How does amphetamine act on the dopamine pathway?

A

Amphetamine releases dopamine in the brain

10
Q

What does the D1 receptor family stimulate? (D1 and D5)

A

Stimulates cAMP

11
Q

What does the D2 receptor family do? (D2, D3, D4)

A
  • Inhibit adenyl cyclase
  • Inhibit voltage-activated Ca2+ channels
  • Open k+ channels

(D2 agonists produce psychotic symptoms in ppl)

12
Q

Where would you find D1 and D2 receptors in the brain?

A

Limbic and striatal areas

13
Q

Bromocriptine

A

D2 agonist

14
Q

Raclopride

A

D2 antagonist

15
Q

Haloperidol

A

D2 antagonist

16
Q

What is clozapine?

A

D4 antagonist

17
Q

What is neuregulin?

A

A signalling protein that mediates cell-cell interactions

-plays CRITICAL ROLE IN THE GROWTH AND DEVELOPMENT of multiple organ systems

18
Q

What is Dysbindin essential for?

A

Essential for adaptive neural plasticity

19
Q

What is DISC-1 involved in?

A

Involved in neurite outgrowth and cortical development through its interactions with other proteins