Psychiatry basics

Question 1

what does the limbic system do ?

Answer 1

The limbic system is the part of the brain involved in our behavioural and emotional responses, especially when it comes to behaviours we need for survival: feeding, reproduction and caring for our young, and fight or flight responses

Question 2

what does the hippocampus do ?

Answer 2

It has a major role in learning and memory.

Question 3

what does the amygdala do ?

Answer 3

Form the core of a neural system for processing fearful and threatening stimuli (4), including:

• > detection of threat
• > activation of appropriate fear-related behaviors in response to threatening or dangerous stimuli.

Question 4

What does the hypothalamus do ?

Answer 4

The hypothalamus is a gland in your brain that controls your hormone system.

Question 5

cingulate gyrus ?

Answer 5

• monitors the body’s response to unpleasant stimulus
• Fear, prediction and avoidance of negative stimuli
• damage here leads to the lack of improper emotions , and diminished pain

Question 6

Basal ganglia ?

Answer 6

• controls voluntary movements
• Also involved in rewards and reinforcing behaviours
• Addiction and habit formation

Question 7

what’s the role of GABA ? in anxiety

Answer 7

1) INHIBITORY neurotransmitter
2) regulatory role at the amygdala and pre frontal cortex
3) Enhanced GABA action => relieves anxiety
DRUGS THAT WORK WITH GABA:
- benzodiazepines
-barbiturates
- alcohol
-sedatives

Question 8

How can PTSD occur ?

Answer 8

• Memories in the hippocampus
• Traumatic memories can activate the amygdala
• Fear response is generated
• Re-experiencing = PTSD

Question 9

Role of Glutamate

Answer 9

major mediatory of excitatory neurotransmission in the brain
receptors : NMDA, AMPA, KA
- imbalance with GABA can cause anxiety
-NMDA hypofunction can cause psychosis

Question 10

neurotransmitters in depression

Answer 10

1) monoamines :
- Serotonin
- Noradrenaline
- Dopamine

Question 11

Serotonin :

• how is it made
• where is it made
• what does serotonin do

Answer 11

tryptophan –> 5HTP –>Serotonin 5HT
made in raphe nuclei in brainstem
-pathways are in brain, gut

(mood, sleep, appetite , cognition, memory , perception,emotion )

Question 12

dopamine
how it made
what is it involved in

Answer 12

Phenylalanine–Tyrosine—L-DOPA—Dopamine

• pleasure , rewards , goal directed behaviour
• Attention
• Motivation
• Emotion
• Motor function

Question 13

how is noradrenaline made ?

what is it involved in ?

Answer 13

L-tyrosine –> L-dopa —>Dopamine –>NA —> Adrenaline

• concentration
• attention
• Motivation
• Energy

Question 14

Effects of stress on monoamines

Answer 14

BDNF=> keeps neurones healthy
stress surpassed BDNF,LOWERS 5HT levels , Acutely increases then chronically depletes NA, da

• BDNF deficiency :
• atrophy
• Apoptosis
• Hippocampus

Dysfucntion of the hippocampus , and Amygdala –> over activity of the HPA axis