"When you have experienced a disturbing effect"
"It triggers your amygdala"
"When the amygdala is overactive-"
"Someone who suffers from PTSD, for example"
"They might have an overactive-"
"Symptoms can include flashbacks, night terrors, intrusive-"
"And sometimes, even chronic physical fatigue"
"The human brain"
"Will hold on to negative experiences more than positive ones"
"Recovery is a long and difficult process"