Carbon dioxide

Nothing to fear but asphyxiation

​Think of the scariest movie you’ve ever seen (for me it’s The Ring). How did you feel when the group of teenagers popped in that video, or the girl climbed out of the TV? When the phone rang and the killer was on the other end? Or when the babysitter was home alone and a shadow passed across the screen? Even though you know it’s just a movie, you still experience that knot in your stomach, pounding heart, sweaty palms and building anxiety that comes with a real stressful or frightening encounter.

These visceral, gut reactions are physiological fear responses our brain and body automatically initiate when in a perceived threatening situation. These experiences are thought to be subserved by the amygdala, an old and deeply rooted part of the brain that is essential in processing emotion, particularly fear. This is partly through connections the amygdala has to the sympathetic nervous system, which controls our basic ‘fight-or-flight’ reactions to danger – preparing us to either stand and fight or flee as fast as we can.