So what was happening in my brain that night?
The picture gets clearer as I read about how information my brain receives through eyes and ears travels inside the brain. It is first transmitted to the auditory and visual thalamus and from there it takes two different paths. The first one goes to the cortex, where it till be integrated with other data and associations, the word “attack” and memories I have of a similar situation, possibly a scene from some horror movie.
The second path goes toward the amygdala and from there alerts the brain stem of danger immediately sending signals to the body to take action (the fight-or-flight response).
The information that goes to the amygdala is significantly less detailed since it can only store sketchy, “low-resolution” images. Therefore much more information can be considered potentially dangerous.
Secondly, it takes a fraction of a second to deliver the message from the thalamus to the amygdala and make the body respond to the potential threat while it can take a few seconds for the more detailed information to reach the cortex and to formulate the response. In other words, when the information goes to the amygdala “what you get is a quick but dirty image rather than the slower, but more realistic portrait created by the visual cortex”.
What does this tell me? For starters, it explains why upon entering a dark room I can jump at seeing a shadow on the wall that for a moment looks like a human figure. It takes a few seconds for the cortex to realise this is only a shadow but before it signals, “It’s alright, you may relax now” my body is ready for a flight because the amygdala has already signaled of the potential danger. Knowing this makes me understand my own reactions in a new light: what I ealier saw as a somewhat neurotic behaviour is the way my brain works. Now I think of it in terms of my-amygdala-being-overprotective. And boy am I glad having this effective survival mechanism implanted somewhere inside my brain: I better jump one time too many than one time too late. ” Better safe than sorry!”.