How do you scare someone who has never felt fear??

Posted On October 28, 2019

Imagine you were completely unable to experience fear –  not from a near drowning or  mugging, not even significant air turbulence during flight.   If you suffer from panic, you might wish for this. But let’s remember that fear is a natural and healthy response to real danger because it alerts us to protect ourselves.

But what if you were completely unable to be afraid?  A very rare neurological disorder that occurs in early childhood (Urbach-Wiethe disease for the curious) causes destruction of the amygdala, our fear center of the brain. People with this condition are essentially unable to experience fear- ever. But for all other emotions, such as excitement, sadness, joy, and disgust, they are just like you and me.

As our ‘fear central’ of the brain, the amygdala has been of intense interest to brain researchers. In the study of those rare individuals without functioning amygdalas, University of Iowa researchers wracked their brains trying to find ways to induce fear.  Snakes, tarantulas, haunted houses, no deal.  One woman in particular, whose history of trauma included muggings and domestic violence, had no hint of fear! In fact, she approached dangerous situations with curiosity rather than avoidance.

After trying everything to frighten these fearless folks, researchers tried the same CO2 challenge test I described in my earlier blog (a single gulp of CO2 enriched air), expecting yet again to see no response. Their theory was that without a functioning amygdala, how could someone experience fear?

To the researchers’ amazement, these individuals instantly suffered panic attacks, and were even more likely than people with panic disorder to experience intense terror in response to the CO2 challenge test.   Their reaction was entirely consistent with evidence around carbon dioxide hypersensitivity, panic attacks and the ‘faulty suffocation alarm’ that I’ve written about previously.  This raises some very intriguing questions as to the association between the amygdala and people who chronically suffer from panic, anxiety disorders and PTSD.

So what do we make of this?  The ‘panic brain’ is more complex than many have assumed.  The more we understand carbon dioxide sensitivity and its role in panic, PTSD, and a few other conditions, the better we will understand why and how Freespira works. In the meantime, our mission to relieve the suffering from these conditions continues.


  1. Feinstein JS, Buzza C, Hurleman R, et al, Fear and panic in humans with bilateral amygdala damage, Nat Neurosci._ 2013 March;16(3): 270–272._doi:10.1038/nn.3323__ _
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