Affective Disorders Part 1

Question 1

What are the cardinal symptoms of a low mood?

(3 marks)

Answer 1

Decreased interest in activies once enjoyed - anhedonia

Lack of energy - anergia

Depressed mood - invariant

Question 2

What are the cognitive symptoms of depression?

(5 marks)

Answer 2

Reduced concentration and memory

Poor self esteem

Guilt

Helplessness

Suicide and self-harm

Question 3

What are somatic symptoms of depression?

(3 marks)

Answer 3

Sleep less

Weight loss

Psychomotor retardation

Question 4

What is hypomania/ mania?

Answer 4

Feeling high/ euphoric as a deviant from normal behaviour by known observer

Question 5

Which is more prevalent in society - bipolar disorder or depression?

Answer 5

Depression

Question 6

What are some physiological effects caused by bipolar disorder?

(2 marks)

Answer 6

Endogenous hormone fluctations e.g. thryroid, menstrual dysfunction

Question 7

Why is bipolar disorder proposed to be a disconnection syndrome?

Answer 7

In ventral striatum some patients in their depressive state show less activity in the ventral striatum

Question 8

What is dopamine dysregulation syndrome?

Answer 8

Dysfunction of the reward system observed in individuals taking dopaminergic medication for an extended length of time

Question 9

How have GWAS helped with identifying MDD?

(1 mark)

Answer 9

By indentifying polymorphisms that may indicate MDD (haven’t foudn any FOR sho yet)

Question 10

How many loci were indentified with ebing associated with MDD?

Answer 10

44 loci

Question 11

What are some of the functional changes in MDD?

(3 marks)

Answer 11

• Decrease in reward processing and pleasure
• Hedonic response - pleasure reward decrease
• Decrease in reward experience

Question 12

What does the medial prefrontal cortex do (mPFC)?

Answer 12

Serves in distinct aspects of workign memory and executive control

Question 13

What anatomical changes occur in MDD in regard to the NAc, amygdala and mPFC?

(3 marks)

Answer 13

The NAc decreases in volume and activity - the amygdala increases in volume. The mPFC decreases in volume and activity - HOWEVER IT IS UNKOWN WHETHER THIS IS A CONSEQUENCE OF THE DISORDER OR AN ONSET TO IT

Question 14

What chemical test is used to measure stress levels in animals after chronic exposure to mild physical stressor?

(2 marks)

Answer 14

• Sucrose prefernce test - normally an animal would prefer the sucrose water but is animal has udergone stress will consume less
• Measure how much animal consumes and whether it is within range of ‘too little’ which may show animal is depressed

Question 15

What is the forced swim test?

Answer 15

Animal is forced to swim in small container until it gives up - signs of depression antidepressed animal will try harder for longer

Question 16

What does the foot shock test show?

(2 marks)

Answer 16

Learned helplessness test - after a few shocks animal will start to give up and just accept the shocks - signs of depression

Question 17

What is the chronic social defeat stress test and what does it show?

(3 marks)

Answer 17

• Put mouse with an ggressor that causes animal stress
• Animals may consume less sucrose indication of depression
• Animal won’t stay in corners or fight - symptom of depression

Question 18

How does stress affect the PFC and hippocampus and what is this associated with?

(2 marks)

Answer 18

• Causes progressive atrophy in PFC and hippocampus - associated with reduction of markers of glutamatergic and inhibitory markers (GAD67)

Question 19

What structural abnormality can be seen after chronic immobilisation of stress to the amygdala?

(1 mark)

Answer 19

• Enhanced branching/ increase in spine formation and hypertrophy

Question 20

What ‘tool’ is used to detect light in animals in optogenetics?

Answer 20

• Microbial opsins - able to change ion flow

Question 21

What is a consequence of dopamine deficieny in depression?

Answer 21

Reduced DAT transporters in those with anhedonia

Question 22

Outline the monoamine hypothesis.

(2 marks)

Answer 22

• States that the underlying pathophysiological basis of depression is a depletion in the levels of serotonin, norepinephrine, and or dopamine

Question 23

What is functional connectivity?

(2 marks)

Answer 23

The temporal coincidence of spatially distant neurophysiological events. Measures the correlation of brain activity between 2 or more active regions in the brain

Question 24

What is BP characterised by?

Answer 24

Dysfunction in the fronto-limbic neural circuit

Question 25

In BP disorder where can an increase of activity be seen in emotional processing?

Answer 25

Limbic structures

Question 26

Where is there reduced functional connectivity in BP disorder?

Answer 26

• Ventral striatum with decreased connectivity strength

Question 27

What does the orbitomedial prefrontal cortex do?

Answer 27

Represents reward value for goals of action

Question 28

Give an example of genetic polymorphisms that have been asscociated with depression.

(2 marks)

Answer 28

MTHFR and ApoE

Question 29

Which allele carriers are likely to develop depressive symptoms or MDD after childhood trauma?

Answer 29

T-allele carriers

Question 30

How does the metabolism of folate by MTHFR contribute to the developement of MDD?

(3 marks)

Answer 30

• MHTFR metabolises folate and makes a methyl donor for sysnthesis of methionine from homoscyteine
• Folate causes synthesis of serotonin and other NTs - decreasing homocysteine levels to have an excitotic effect via Ca²⁺ glutamate receptors
• \Folate is needed for biosynthesis of antidepressants - so less folate less senstivity to antidepressants