QUOTE : When our internal voice starts criticizing us, lashing out, it can feel like we’re under attack. Because our brain doesn’t distinguish between imagination and reality, these internal attacks are perceived by our mind just as a real, physical attack would be, and they can generate an automatic physical reaction known as the threat response or fight-or-flight response. The effects of this activation are well-known. Just as a zebra reacts to the stress of being chased by a lion, the human body shoots adrenaline and cortisol (stress hormones) through its veins, and directs all its resources toward crucial functions: elevated heart and breathing rates, muscle reaction, vision acuity, and so forth. The body is no longer concerned with living ten more years, but with surviving ten more minutes. It shuts down nonurgent functions such as muscle repair, digestion, and the immune system,6 as well as “superfluous” functions such as cognitive reasoning. In other words, because it’s not critical to survival, intelligent thinking gets shut down.