Task 2

Question 1

Why is it a two-system model?

Answer 1

dual brain systems provide us with
the flexibility to react instantly (subcortically, unconsciously) or more thoughtfully
(‘consciously’) to environmental threats

Question 2

Which ‘different’ brain pathways/processes are involved in emotional responsiveness vs conscious experience of fear (emotions)?

Answer 2

1. thalamo-amygdala route –> defensive responses
2. thalamo-cortico-amygdala route –> FEAR
   - -> concsious experience: higher-order cortex important (l&mPFC, insula)

Question 3

Does LeDoux see the amygdala as the centre of explicit emotional experience?

Answer 3

amygdala is not itself responsible for the experience of fear but can detect & respond to present or imminent threats –> higher-order circuits important for experience

Question 4

What (implicit) processes does LeDoux think underlie conscious emotional experiences?

Answer 4

-circuits in higher-order association cortex
–> areas:
• Lateral & medial PFC
•Insula

Question 5

Why is fear not what causes threat responses?

Answer 5

• fear –> due to higher-order association cortex

- threat responses –> not dependent on cortex

Question 6

Why can people without an amygdala still feel fear?

Answer 6

-since amygdala not itself responsible for fear (but cortex!)

Question 7

What does the figure mean (PTSD& amygdala activity)?

Answer 7

-PTSD: hyperactive amygdala
–> greater amygdala responsiveness to
negative pictures (vs fixation cross) in
PTSD patients

Question 8

What could a hyperactive amygdala in PTSD patients imply?

Answer 8

-amygdala hyperactivity:: persistently elevated fear response & hypoactivity in frontal regions suggests a reduced potential for top-down regulation of fear & fear extinction
==> reduced PFC control on sub-cortical ‘survical’
pathway including amygdala

Question 9

How could conditioned emotion/fear responses be involved in this? How to explain higher amygdala responsiveness to negative stimuli in
anxiety disorder patients? Particular role for conditioned emotional responsiveness

Answer 9

• Fear conditioning: depends on amygdala

- decreased top-down control (PFC)

Question 10

‘Aversive conditioning network’ including different brain areas/circuits (Holzschneider et al): what are the most important ones?

Answer 10

anterior cinculate cortex (ACC), anterior insula (AI) & amygdala

Question 11

How does this aversive conditioning network function in patients with anxiety disorders? –> PTSD

Answer 11

• hyperactive amygdala & hypoactivity in the mPFC & ACC

- less active hippocampus

Question 12

How does this aversive conditioning network function in patients with anxiety disorders? –> OCD

Answer 12

• striatal dysfunction leads via direct & indirect pathways to inefficient thalamic gating –> hyperactivity within the OFC &ACC
• -> amygdala hyperactivation in OCD patients might reflect general emotional hyperarousal rather than OCD-related anxiety

Question 13

Global workspace theory (LeDoux)

Answer 13

subjective experience emerges through widely distributed reentrant circuitry, with prefrontal areas playing an especially prominent role

Question 14

Higher-order theory (Le Doux)

Answer 14

subjective experience arises from a more delimited circuitry, especially involving a prefrontal hub, which supports thoughts about lower-order information