Amygdala (Metaphor)
The amygdala is a pair of almond-shaped brain structures that play a vital role in processing emotions, particularly fear and aggression. Van der Kolk refers to the amygdala as "the brain's smoke detector" due to the way it signals whether or not something is a threat (Chapter 4).
The Medial Prefrontal Cortex (Simile)
Van der Kolk compares the frontal lobes and particularly the medial prefrontal cortex to a watchtower that interprets the alarms set off by the amygdala. This occurs in response to perceived threats.
The Rational Brain and the Emotional Brain (Simile)
Paul MacLean, who developed the triune brain theory, compares the relationship between the rational brain and the emotional brain to that between a somewhat competent rider and his unruly horse. Things go smoothly in calm weather and on an easy path, but unexpected sounds or threats can cause the horse to bolt. Likewise, traumatized people may not be able to manage their behavior when overwhelmed by perceived threats.
Diagnoses (Metaphor)
In Chapter 7, van der Kolk speculates that a "blizzard of diagnoses" was obscuring the underlying trauma experienced by the troubled children he worked with at the Massachusetts Mental Health Center. A blizzard is a severe snowstorm characterized by strong winds, low visibility, and significant snowfall. Comparing the volume of diagnoses to a blizzard indicates the danger in using myriad clinical labels without considering underlying factors or root causes.
