Lecture 35: Fear and anxiety

Question 1

***How do we distinguish fear from anxiety?

Answer 1

fear – adaptive emotional response to something. Brief, present/imminent, specific/clear threat, facilitates escape

anxiety - caused by things prolonged in nature, future focused, diffuse or poorly defined threat, promotes avoidance, caution and hyper vigilance.

Question 2

***describe LeDoux’s low vs high roads to fear

Answer 2

low road: a fast pathway from sensory receptor to the thalamus to the amygdala that bypasses the cortex; it enables rapid, automatic, unconscious reactions to the broad outlines of potentially dangerous stimuli

Low Road: thalamus → amygdala
the emotional stimulus would be expressed; doesn’t go through cortical processing
will get autonomic response

LOW ROAD: fear conditioning cab be a rapid process that does not require conscious appraisal

VS

high road: allows for complex, contextualized processing of stimuli followed by conscious, deliberate responding; influenced by social and personal decision making processes and can reflect culture-specific emotional responses

High Road: emotional appraisal based on cortex
Thalamus → cortex → Amygdala
can either suppress or enhance fear. Why Evolutionary Adaptive? allows for quick action, such like fleeing in case predator is present

HIGH ROAD: learning about more complex stimuli (e.g. contexts) requires longer processing time and post-contidioning consolidation periods

Question 3

***what is the neurological basis for the relapse of fear after fear extinction?

Answer 3

1. passage of time: spontaneous recovery
2. with a change in context: renewal effect
3. exposure to the US: reinstatement
4. CR’s can be rapidly relearned: rapid re-acquisition effect

Question 4

**what is the role of the prefrontal cortices in the expression of fear?

Answer 4

1. repeated presentation of US without CS results in a loss of the CR during extinction
2. maintained reduction in CR when tested again the same day
3. extinguished fear can return due change in content (renewal), re-experiencing the US (reinstatement), or the passage of time (spontaneious recovery)

mPFC PLAYS A LONG MAJOR ROLE IN THE LONG TERM MEMORY FOR EXTINCTION

Question 5

***how can we treat fear?

Answer 5

1. exposure therapy
2. systematic desensitization
3. pharmacological: benzodiazepenes (to calm down), serotonin (for ocd, anxiety disorders, and anorexia), and beta blockers