They do - their amygdala. "fMRI testing at the Medical University of South Carolina tilted the scales toward precisely that explanation — an underactive amygda

They do - their amygdala. "fMRI testing at the Medical University of South Carolina tilted the scales toward precisely that explanation — an underactive amygdala, not a negligent mother — by confirming that Honnold’s fear circuitry really does fire with less vigor than most." https://www.nytimes.com/2017/06/09/opinion/el-capitan-my-el-capitan.html https://www.nytimes.com/2017/06/09/opinion/el-capitan-my-el-...