Schizophrenia and affective disorders

Question 1

Approximately what percentage of people are affected by sz?

Answer 1

1%

Question 2

Who coined the term schizophrenia (‘split mind’)?

Answer 2

Bleuler (1911) - refers to a break from reality.

Question 3

What are the positive symptoms of sz?

Answer 3

Hallucinations, thought disorders, delusions (persecution, grandeur and control).

Question 4

What are the negative symptoms of sz?

Answer 4

Flattened emotional response, poverty of speech, lack of initiative and persistance, anhedonia and social withdrawal.

Question 5

What are cognitive symptoms of sz (can be assessed in the lab)?

Answer 5

• Difficulty sustaining attention
• Low psychomotor speed
• Deficits in learning and memory
• Poor abstract thinking and problem solving.

Question 6

How hereditary is sz?

Answer 6

46% both parents, MZ twins 48%.
Parent 6% sibling 9% children 13%
Spouse 2%

Question 7

What does the dopamine hypothesis suggest?

Answer 7

Szics have too much dopamine - Chlorpromazine (antagonist) diminishes symptoms and over-activity of dopamine neurons/dopamine agonists (e.g. amphetamines) can lead to +ve symptoms.

Question 8

What did Laruelle (1996) find related to dopamine in szics?

Answer 8

• More dop release in szics than controls

- More released = more +ve symptoms.

Question 9

Where is dopamine released from?

Answer 9

The ventral tegmental area in the nucleus accumbens and amygdala (reward centre = activity strong reinforcer).

Question 10

What did Snyder (1974) find?

Answer 10

Szics report elation at the start of a szic episode.

Question 11

What did Fibiger (1991) find?

Answer 11

Paranoid delusions are caused by activity in the amygdala - it’s involved in learning emotional responses (esp. fear).

Question 12

What brain abnormalities are often seen in szics?

Answer 12

Enlarged ventricles.

Question 13

What is the seasonality effect?

Answer 13

• Those born in spring seem to be at much higher risk for sz.
• Mother would have been in 2nd trimester (brain development) during winter when flu is more prevalent.
• Davis et al. (1995) - flu virus could cause brain damage.

Question 14

Discordance in MZ twins may suggest a post natal environmental effect, but…

Answer 14

Placenta sharing also seems to have an effect:

• Monochorionic concordance = 60%
• Dichorionic con. = 10.7%.

Question 15

What are symptoms of depression?

Answer 15

Low energy levels, anhedonia, loss of appetite (food and sex), sleeping problems, constipation.

Question 16

What is anhedonia?

Answer 16

Inability to feel pleasure.

Question 17

What are symptoms of mania?

Answer 17

Euphoria, delusions, poor attention span, lack of sleep, self-importance.

Question 18

What is the prevalence of bi-polar depression?

Answer 18

1%, equal for men and women.

Question 19

What is the prevalence of unipolar depression?

Answer 19

About 6%, 2-3x more likely in women than men.

Question 20

What did Rosenthal (1971) find about the hereditability of affective disorders?

Answer 20

10x more likely to suffer if a close relative does.

Question 21

What did Gershon et al. (1976) find about the hereditability of affective disorders?

Answer 21

MZ concordance 69%, DZ 13%.

According to Prince (1968) same whether reared together or apart.

Question 22

What is the Monoamine hypoothesis?

Answer 22

The idea that depression is caused by low activity of monoamine neurons.
(As dopamine agonists have no effect it’s likely that monoamine neurons are involved through serotonin and/or noradrenaline.)

Question 23

What are the different pharmacological treatments for affective disorders?

Answer 23

• Iproniazid. Inhibits MOA (increases serotonin, dopamine and noradrenaline). Discovered as side effect of TB treatment, unpleasant side effects.
• Lithium (carbonate) used to treat mania. Why it works is not fully understood – possibly stabilises serotonin release. Side effects include diuresis, hand tremors, weight gain and thirst.

Question 24

What is one of the side effects of resperine, and what does this imply?

Answer 24

Used to treat high BP, monoamine antagonist and has the side effect of depression (Sachar and Baron, 1979) - implies role of monoamines.

Question 25

What did Vogel et al. (1990) find?

Answer 25

That preventing REM sleep acts as an antidepressant. Support from Scherschlicht et al. (1982) who studied the effects of 20 antidepressants and found that they all reduced REM, most increased SWS.