Lecture 51: PTSD

Question 1

What are the 6 criteria for PTSD?

Answer 1

1. Person experiences, witnessed, confronted with threatened death/serious injury
2. the traumatic event is persistently RE-EXPERIENCED in one or more ways
   
   • intrusive recollections of trauma, nightmares, flashbacks, emotional reactions to triggers
3. Avoidance and Numbing
4. Increased arousal
5. Duration of more than 1 month
6. Clinically significant distress or impairment in function

Question 2

What is PTSD a risk factor for?

Answer 2

• high school drop out
• teenage childbearing
• marital insability
• unemployment
• loses an average 3.6 days/month of work

Question 3

What is the prevelance of PTSD in the US?

Answer 3

About 7% of population suffers from PTSD

1/3 will have symptoms 10 years after trauma

Question 4

How do you extinguish learned fear?

Answer 4

You do so through therapy?

PTSD represents impaired fear extinction

Question 5

What is fear conditiong?

Answer 5

When a conditioned stimulus (like a sound) is paired with an unconditioned stimulus (shock) that leasd to a conditioned response (freezing in your tracks in response to tone)
Can be studied in animals

Question 6

What is an example of fear conditioning in PTSD?

Answer 6

Conditioned Stimulus = dark street
Unconditioned stimulus = mugging
Conditioned response = fear of dark streets

Question 7

What is the prolonged exposure therapy for PTSD?

Answer 7

Using a conditioned stimulus and presenting NO unconditioned stimulus
(dark street with nothing bad things happening)
Also, you can have memory of trauma (CS) but no US which will lead to fear extinction

Question 8

What are brain correlates of PTSD?

Answer 8

i. amygdala (cues)
ii. hippocampus (contextual)
iii. ventromedial PFC
- brain needs to RECALL fear extinction

Question 9

What happens with hippocampal size with PTSD patients?

Answer 9

PTSD patients have SMALLER hippocampal volumeS

Question 10

What happens during extinction recall in PTSD patients?

Answer 10

1. ENHANCED amygdala
2. Dampened vmPFC activation (means less recall of condition to dampen fear)
   
   • impaired recall of extinction learning
3. increased activity in dorsal ACC

Question 11

What happens when you have no ventromedial prefrontal cortex in context of fear learning?

Answer 11

You LOSE recall of fear extinction…so the fear response remains

Question 12

What are the associations between PTSD and fear extinguished?

Answer 12

Those with PTSD have IMPAIRED fear extinction

Cannot overcome fear

Question 13

How can fear responses return?

Answer 13

1. after passage of time
2. In a specific context (contextual renewal)
3. After unpaired US presentation
   If you hear “that was easy” in staples, brian will probably not jump lol

Question 14

What are the effects of SSRIs on hippocampal size?

Answer 14

INCREASES hippocampal size

-increases ability for fear extinction

Question 15

Where are the neural bases of fear extinction recall: non-human animals?

Answer 15

ventromedial PFC

Question 16

What is prolonged exposure for PTSD?

Answer 16

Consists of imaginary exposure (repeatedly revisiting trauma memory trauma in safe context
In vivo exposure: repeatedly and systematically approaching in real life situations that are feared even tough objectively they are safe
-discussing one’s reaction to retelling memory and to in vivo exposure exercises

Question 17

What does PTSD treatment do for the brain?

Answer 17

1. they INCREASE activity in ACC

2. DECREASE activity in amygdala