Week 3 - Anxiety

Question 1

What are the 2 main hormonal reactions to fear?

Answer 1

Cortisol
Noradrenaline

Question 2

What part of the brain activates when aroused by fear?

Answer 2

The amygdala

Amygdala alerts other brain structures including the hypothalamus and the locus coruleus

Information is then sent from the thalamus to the cortex and basal ganglia for processing

Question 3

What is the main neurotransmitter for GAD?

Answer 3

Noradrenaline - overacting in central and peripheral nervous system

Question 4

Serotonin in GAD

Answer 4

Increased activity due to a lack of serotonin in:

Basal Ganglia
-inability to adequately process information from the environment

Cerebral Cortex (PFC)
Limbic cortex/Amygdala

5HTa1 receptors!

Question 5

Neurotransmitters for OCD

Answer 5

Noradrenaline
Seratonin
Dopamine

Question 6

Which 2 brain areas causes OCD?

Answer 6

Lack of communication between
Frontal (cingulate), striatal and thalamic structures

Question 7

Noradrenaline in OCD

Answer 7

don’t have sympathetic outflow

Question 8

Serotonin in OCD

Answer 8

Increased activity due to LACK of serotonin in:

Basal ganglia/thalamus
Cerebral Cortex (PFC)
Hippocampus (memory)
Limbic cortex/Amygdala

Question 9

Dopamine in OCD

Answer 9

Increased dopamine function in basal ganglia(nigrostriatal) produces repetition of habits

Question 10

PTSD amygdala and hippocampus

Answer 10

Amygdala dominates information from the hippocampus - leads to exacerbation of negative emotion linked to the memory or event

Question 11

What does the hypothalamus do?

Answer 11

Regulates autonomic nervous system (peripheral)

Question 12

3 main brain structures in PTSD

Answer 12

Hippocampus
Amygdala
Hypothalamus

Pituiatry gland activates: cortisol

Question 13

What activates the hippocampus?

Answer 13

cortisol

more cortisol - the hippocampus shrinks/cells kill neural pathway of hippocampus to hypothalamus
Hippo is less efficient at inhibiting ACTH release

amydala takes over

Question 14

Common neural circuits of anxiety

Answer 14

All noradrenaline systems are overactive
Select serotonin neurons are underactive
OCD also has increased dopamine in BG area

Question 15

How do barbituates work?

Answer 15

gaba a receptor agonists - enhance IPSP of chloride receptor

Question 16

How do benzo’s work?

Answer 16

gaba agonists
have their own binding site on gaba receptors - Bz1 and Bz2

Allows for chloride to get in by binding to receptor site and opening the channel - allows channel to stay open for longer - more IPSP

Question 17

Pro’s on benzo’s

Answer 17

Reduce anxiety and aggression
can produce sedation for insomnia
effective immediately is taken orally

Question 18

2nd generation anxiety meds

Answer 18

decrease noradrenaline
increase seratonin

Question 19

What drugs decrease noradrenaline for anxiety and how do they work?

Answer 19

B-adrenoreceptor antagonists (beta blocker) - stop the production of noradrenaline with produces sympathetic overload

Question 20

What drugs increase seratonin for anxiety and how do they work?

Answer 20

5HT1A receptor - agonists - increase IPSP - acts like seratonin

SSRI’s - stop the re-uptake of seratonin after post-synaptic potentialW

Question 21

What protein is involved in serotonin

Answer 21

Gi - inhibitory G protein

Question 22

SSRi’s

Answer 22

Kepp seratoinin in the synapse - block re-upatke
With next action potential - more serotonin stays in the synapse

Question 23

What is the latency to become effective?

Answer 23

5 Ht1A receptors are also pre-synaptic and are more sensitive
When serotonin binds pre-synaptically, serotonin release is stopped
Cells need to de-sensitise and remove themselves before drugs can be effective (2-3 weeks) - usually why people don’t see affect for this time
Need to de-sensitse