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Flashcards in schizophrenia Deck (44)
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1
Q

what is the most common psychotic disorder?

A

schizophrenia

2
Q

what is schizoaffective disorder?

A

schizophrenia and bipolar disorder

3
Q

key characteristics of schizophrenia?

A
  • Early onset (late adolescence)
  • Prevalent
  • Disabling and chronic - chronic relapsing disorder
4
Q

is schizophrenia a condition to do with mood?

A

not a condition of mood, but perception of thoughts –

  • mental state out of touch with reality, associated with delusions and hallucinations
  • abnormalities of perception, thought & ideas
  • profound alterations in behaviour (bizarre and disturbing alienation)
5
Q

prevalence of schizophrenia

A

1% of population

ethnicity and gender have no effect

6
Q

schizophrenia – 4 phases?

A
  1. The prodrome
  2. Active phase
  3. Remission
  4. Relapse

Cycles between remission and relapse common

7
Q

what can szn patients tell?

A

patients can sometimes tell when a relapse is coming

8
Q

prodrome phase

A

Late teens/early twenties: often mistaken for depression or anxiety. Can be triggered by stress

9
Q

active phase

A

Onset of positive symptoms. Differentiation of what is and isn’t real becomes difficult. Usually lasts for 4-6 weeks

10
Q

remission

A

Treatment return to ‘normality’, can last for years

11
Q

3 classes of schizophrenia symptoms

A

positive, negative, cognitive

-two or more symptoms must persist for at least 6 months to be classed as schizophrenia

12
Q

positive symptoms?

A

present in the onset

Hallucinations (e.g. visual, auditory)
Delusions
Disorganised thought/speech
Movement disorders

13
Q

negative symptoms?

A

kick in later, more pronounced

Social withdrawal
Anhedonia
Lack of motivation
Poverty of speech
Emotional flatness
14
Q

cognitive symptoms?

A

very often present later on in life

Impaired working memory
Impaired attention
Impaired comprehension

15
Q

what are hallucinations?

A

when a perception is experienced without stimulus (positive symptoms)

Most commonly auditory - patients hears
	Voices talking about them (3rd person)
	Voices talking to them
	Voices giving a running commentary
	 Voices echoing their thoughts (thought echo)

Patients may engage in a dialogue with the voices or obey their commands

16
Q

what are delusions?

A

fixed, unshakable belief - not consistent with cultural/ social norms
-often paranoid or persecutory

17
Q

Motor, volitional and behavioural disorders in schizophrenia

A

-Bizarre postures, strange mannerisms
-Altered facial expression – grimacing
-State of catatonia – motionless, mute, expressionless, uncomfortable or contorted postures
-extreme hyperactivity (destructiveness, walk round naked)
Impulsive behaviour – violent acts; murder w/o reason

18
Q

schizophrenia - killing?

A

people can become violent, and they often do not feel regret after killing due to their emotional flatness

19
Q

Formal thought disorder

A
  • Disturbances in thinking → unintelligible speech
  • Derailment of speech
  • Loosening of associations; failure to follow train of though to its conclusion
  • Poverty of speech (speech fails to convey sense/information)
  • Manifests as distorted or illogical speech - neologisms, new words formed
20
Q

social withdrawal

A

Patients withdraw from their families and friends, spend a lot of time on their own.

  • Lack of initiative or motivation
  • Do not want to do anything
  • No longer interested in things that used to interest them
21
Q

cognitive deficits

A
  • Deficits in SELECTIVE attention, problem solving and memory
  • Blunted affect
  • Decreased responsiveness to emotional issues
  • Expression is inappropriate to circumstances
22
Q

lack of insight

A

no/lack of understanding what’s wrong.

-patients usually do not accept that any thing is wrong or that treatment is necessary

23
Q

The aetiology of schizophrenia

A
genetics
-SCZ isn’t directly inherited, but can ‘run in families’
‘Candidate’ risk genes:
                   Gene deletions
                   Gene mutations

environmental factors

  • Pregnancy/birth complications
  • Stress
  • Drug use

-current thinking is that a person needs both to manifest the disease

24
Q

what do twin studies show?

A

shows that there is a genetic component to the disease
Not inherited, but there IS a risk

50% chance of developing schizophrenia if one twin diagnosed

25
Q

candidate risk genes?

A

COMT
DISC1
GRM3
-Possessing these abnormal genes doesn’t mean you will definitely get schizophrenia – similarly, some people who have schizophrenia do not have these genetic abnormalities
-Increased vulnerability of developing SZN

26
Q

influenza

A

Finnish study reported a spike in schizophrenia for people who were foetuses during the 1957 influenza epidemic

27
Q

Pregnancy/birth complications association with schizophrenia

A

Low birth weight
Premature birth
Asphyxia during birth
-caused of early life stress, associated with a slightly higher risk of developing schizophrenia

28
Q

name some causes of stress….

A

-Moving country
-Early-Life Bereavement
-Loss of >1 first-degree relative further increased risk
-Loss of job/home/relationship
-Physical/emotional/sexual abuse
The mechanism by which stress may trigger schizophrenia is unknown

29
Q

Drug Use

A

Cannabis is number 1 used drug of abuse other than alcohol

Early use of cannabis is a big risk factor

30
Q

which pathway is involved in producing positive symptoms of szn?
dopamine hypothesis of schizophrenia

A

Hyperactivity of mesolimbic dopaminergic pathway, increased release of dopamine.

31
Q

amphetamine?

A

increases dopamine dramatically in the mesolimbic pathway, and has been shown to play a role of psychotic like symptoms

32
Q

which pathway is involved in producing negative symptoms of szn?

A

Low activity of mesocortical pathway

33
Q

what do we need to do to the pathways to treat szn?

A

increase DAergic transmission (D1) in mesocortical regions, decrease DAergic transmission (D2) on mesolimbic regions

34
Q

evidence against the dopamine hypothesis of schizophrenia

A

you would expect to find high levels of dopamine in the CSF, but this hasn’t been found

35
Q

Brain Structure Abnormalities

A

scans have been looked at of twins, one of whom suffers with schizophrenia - clear structural abonormalities

  • enlarged lateral ventricles – smaller hippocampus
  • reduction of gray matter
  • size of the brain is slightly smaller
36
Q

hypofrontality?

A

Reduced activity in frontal cortex and Reduced blood flow to the frontal cortex
-hypofunction

37
Q

glutamate/NMDA hypofunction hypothesis

A
  • decreased glutamate
  • low levels of NMDA receptor/glutamate in pre frontal cortex is associated with the negative szn symptoms
  • mice, genetically removed NMDA receptors and mice produced szn-like episodes

Glutamate excitatory on GABAergic neurons
DA inhibitory on GABAergic neurons
Too little glutamate, too much DA – uninhibited sensory input to limbic regions (NAc, Hi, Amy)

38
Q

Hyperactivity of serotonin receptors

A

Many antipsychotics antagonise 5-HT receptors
5-HT activates DA pathways
5-HT2A antagonism – may contribute to antipsychotic effect, may reduce movement disorder side effects

39
Q

main current theory?

A

Over stimulation of mesolimbic D2 receptors
Hypoactivity of frontal cortical D1 receptors
Reduced prefrontal glutaminergic activity
5HT involved

40
Q

why would anti-psychotics cause a loss of reward?

A

because they affect d2 receptors everywhere

41
Q

2 types of antipsychotics?

A

typicals
-‘first generation’
First developed in the 1950s
Mainly antagonise D2 receptors

atypicals
-‘second generation’
First developed in the 1980s
Mainly antagonise D2 and 5-HT2A receptors

42
Q

why would anti-psychotics have endocrine effects?

A

because there are d2 receptors in the brain, and dopamine binds and decreases prolactin release
antipsychotics are d2 receptor blockade, therefore causing increased PRL levels, so breast swelling, lactation and impotence

43
Q

why might anti-psychotics cause hypotension?

A

due to the alpha adrenoceptor blockade

44
Q

why do anti-psychotics cause decreased pleasure?

A

dopamine receptors involved in reward system