Neurobiology of Mood Disorders

Question 1

Describe the hypothesis of depression

Answer 1

Deficit of monoamines (Serotonin, Norepinephrine, Dopamine, GABA, Somatostatin)
Excess of certain neurotransmitters (Ach, Substance P, CRH)

Question 2

In depression, why do you get adrenal hypertrophy?

Answer 2

Because there is hypersecretion of CRF (higher levels of ACTH & higher stimulation of adrencorticoid cells.)

Question 3

Higher levels of cortisol in depression leads to

Answer 3

high levels of glucose, pro inflammatory immune mediator release & disturbances of neurotransmitter levels

Question 4

In depression, serotonin function is usually abnormal before, during & after depressive episodes. T/F

Answer 4

True (This may explain why 80% of patients have recurrences of major depressive episodes.)

Question 5

Norepinephrine deficit is related to adverse childhood events

Answer 5

True
(Adverse childhood experiences can produce an over-active responsiveness in this system that persists into adulthood.
In situations that most people may not find too stressful, the vulnerable depressed individual does feels very stressed and may deplete NE - Depletion of NE causes depression in recovered patients but not unaffected people. Depletion of NE related to feelings of hopelessness which is a part of major depression.)

Question 6

Name the monoamines that are deficient in depression

Answer 6

Serotonin, Norepinephrine, Dopamine, GABA, Somatostatin

Question 7

In depression, there is an excess of Ach, Substance P, CRH

Answer 7

True

Question 8

Why is dopamine deficit significant in depression?

Answer 8

Dopamine is the major neurotransmitter associated with the appeptive system.
Mesolimbic dopaminergic system is involved in the control of motivation and rewarding experiences
Hypofunction of the dopamine system has been proposed as an underlying brain mechanism of the loss of pleasure/interest experienced in depression

Question 9

GABA is the main neurotransmitter mediating neural inhibition. There is a DEFICIT of this neurotransmitter in depression.

Answer 9

True

Question 10

Self-harm promotes the release of endorphins

Answer 10

True

Because it brings temporary distress reduction - through negative reinforcement, these behaviours tend to be repeated

Question 11

Bipolar is a multifactorial disease with a strong genetic component

Answer 11

True

Question 12

What monoamine HYPERACTIVITY is indicated in mania?

Answer 12

Norepinephrine

Dopamine - asscoiated with appetitive system.

Question 13

Which monomanine HYPOACTIVITY i indicated in the mood instability element of bipolar?

Answer 13

GABA

Question 14

What may you see in a PET scan of someone with schizophrenia?

Answer 14

Hypoactivity of the prefrontal lobes (reduced volume & grey matter)
Enlarged cerebral ventricles

Question 15

PET scan is useful in diagnosing schizophrenia

Answer 15

false

neurovariability means that imaging isn’t useful.

Question 16

Which pathways are HYPERACTIVE in schizophrenia?

Answer 16

Dopaminergic - appetitive system

Question 17

There have been sme identified gene patholgoies in the pathology of schizophrenia

Answer 17

True
Neuregulin—a signalling protein which plays a key part in growth & development in organ systems.
Dysbindin—essential for neuroplasticity.
DISC-1 involved in neurite outgrowth

Question 18

Heavy cannabis use, African-Carribean, Urban Dwelling, Perinatal complications - risk factors for?

Answer 18

Schizophrenia

Question 19

Autism is >90% more likely in offspring

Answer 19

True

Question 20

Name some diseases implicated in Autism

Answer 20

Rubella (German measles) in the pregnant mother
Tuberous sclerosis
Fragile X syndrome (the most common inherited form of intellectual disability)
Encephalitis (brain inflammation)
Untreated phenylketonuria (PKU)

Question 21

In ADHD you may see underactivity in which lobe?

Answer 21

Frontal

Question 22

In ADHD which pathways are HYPERACTIVE?

Answer 22

Dopaminergic ( excessively efficient dopamine-removal system - higher concentration of dopamine transporters - called re-uptake inhibitors.)

Question 23

ADHD tends to aggregate in families

Answer 23

True (60% increased risk in offspring of adults with ADHD. 15% risk in siblings)

Question 24

Describe Type 1 & Type 2 trauma in PTSD

Answer 24

Type 1: trauma: single incident, sudden, unexpected

Type 2: complex trauma, repetitive, Ongoing abuse, developmental, betrayal of trust. Expected.

Question 25

Which neutrotransmitter is increased in benzodiazepene use?

Answer 25

GABA

Question 26

Which NT are associated with each of the appetitive & aversive systems?

Answer 26

Appetitive - Doapmine

Aversive- Serotonin