PTSD Flashcards
Criteria for PTSD in DSM
- arousal
- negativity
- avoidance (of pot. cues)
- reexperiencing
- having being exposed to trauma
- for one month
GR receptor
= glucocorticoid receptor
abundant in brain
corticosteroid
only activated under high stress
MR receptor
= mineralocorticoid receptor
corticosteroid
in hippocampus
usually blocked
threshold lower in PTSD people
SAM
sympatho-adrenal-medullla
1. medulla
2. solitary tract nucleus
3. locus coereleus
4. alpha2 in PFC
5. alpha1 and beta2 in amygdala
HPA
- adrenal cortex
- hypothalamus
corticosteroid action
nuclear receptor
-> intracellular
affects gene expression
-> slower
brain in PTSD
less hippocampus activity during retrieval
more amygdala during retrieval & encoding
-> hyper sensory encoding
memory traces in PTSD
bad declarative memory
-> less context
highly emotional
more amygdala connections
retrieval out of the blue
-> small cues are enough to retrieve them
mechanisms affected in PTSD
- abnormal fear learning
- exaggerated threat detection
- impaired emotion regulation
abnormal fear learning
there are always a competing “fear” and “safety” memory
in PTSD, fear wins
more amygdala, less PFC
exaggerated threat detection
“cues over context”
stronger salience netowkr
amygdala has tighter connections
impaired emotion regulation
especially in reappraisal
impaired executive control
PTSD cases after trauma
20%
alpha 2
noradrenaline receptor
PFC
activates PFC
alpha 1 & beta 2
noradrenaline receptor
amygdala
inhibits PFC
PFC - amygdala tradeoff mechanism
alpha 2 vs alpha 1 & beta 2
pro vs contra
noradrenalin activation modes
ongoing tonic
reactive phasic
stress and memory
increased LTP
corticosteroid noradrenaline dependency
corticosteroids only work if noradrenaline flows
amygdala under stress
lower selectivity
higher sensitivity
