The woman who knows no fear

A 44-year-old woman with a rare form of brain damage can literally feel no fear, according to a case study published yesterday in the journal Current Biology. Referred to as SM, she suffers from a genetic condition called Urbach-Wiethe Disease. The condition is extremely rare, with fewer than 300 reported cases since it was first described in 1929, and is caused by a mutation in a gene on chromosome 1, which encodes an extracellular matrix protein. The symptoms vary widely, and in about 50% of cases there is calcification, or hardening, of structures in the medial temporal lobe of the brain. In SM's case, it led to degeneration of the amygdala (below), a small, almond-shaped structure known to be involved in fear and other emotions.

SM has been studied extensively during the past two decades. Early investigations showed that her non-verbal visual memory was signficantly impaired but that otherwise she had an IQ in the low-average range. She also displayed inappropriate social behaviours, quickly becoming friendly with the experimenters and making sexual remarks, due to disturbed executive control. Subsequently, it was found that she was unable to recognize emotions in facial expressions, and a study published earlier this year showed that the brain damage had eliminated her monetary loss aversion - that is, she makes risky financial decisions that most of us would avoid because of a fear of losing money.

None of these previous studies assessed her experience of fear, however. Justin Feinstein of the University of Iowa and his colleagues therefore tested SM's fear responses, using a very simple method - by trying to scare her. First, they took her to an exotic pet store and exposed her to snakes and spiders, which, she had told them, she "hated" and "tried to avoid". Nevertheless, she seemed fascinated by the large collection of snakes, and was compelled to touch and poke the larger and more dangerous ones, as well as a tarantula, but had to be stopped in case she got bitten. Throughout the visit, she was asked to rate her fear on a scale of 0 to 10, and her ratings were never greater than 2. 

Next, the researchers took SM on a Halloween visit to Waverly Hills Sanatorium in Louisville, Kentucky, which features people dressed as monsters, murderers and ghosts and is reported to be "one of the most haunted places in the world". When they arrived, she voluntarily led the researchers and a goup of five strange women around the house, walking into dark corners and hallways without hesitation. The hidden monsters tried to scare her numerous times, unsuccessfully. Whereas the five other women in the group screamed loudly whenever they encountered one, SM laughed and smiled at them, and even scared one by poking it in the head because she was curious about how it felt. She rated her fear level at 0 throughout, saying instead that she found it exciting.

SMs amygdala damage.jpg

Finally, they showed her scenes from scary movies, such as The Ring, The Blair Witch Project and The Shining, interspersed with clips that induce disgust, anger, surprise, and happiness. She laughed at a collage of scenes showing babies and small children doing funny things, was disgusted by a scene from Pink Flamingos in which a cross-dresser eats dog faeces, and expressed anger at a scene from Cry Freedom in which a group of children are shot and killed by soldiers. But she did not express fear at any point while watching the horror movie scenes - she told the researchers that she found them exciting, and even asked for the title of one of the movies so she could rent and watch it.

SM reports having experienced fear as a young child. She recalls being afraid of the dark, and remembers when her older brother jumped out from behind a tree while she walked through a cemetary, making her run away screaming and crying. She also appears to understand the concept of fear. She uses words such as afraid, terror, panic and frightened appropriately during conversations, and can recognize the emotion in other peoples' voices.

But based on interviews with her and her three children, the authors suggest that she probably has not experienced fear at all throughout the whole duration of her adult life, despite having encountered an unusually high number of traumatic and life-threatening events. Aged 30, she had a knife held to her throat by a drug addict while she walked through a park at night, but did not panic and walked away calmly when he let her go. She has also been held at gun point, was nearly killed in an act of domestic violence, and has been the victim of numerous crimes in the poverty-stricken area in which she lives.

SM therefore seems unable to detect threats in her environment and, as a result, does not actively avoid potentially dangerous situations as most of us would. Feinstein and his colleagues argue that this is because the amygdala is essential in triggering a state of fear. The amygdala is but one component of a network of brain structures that normally generate an appropriate fear response, but in its absence this response cannot be mounted, so that the experience of fear is severely diminished. The researchers further suggest that she may be immune to the effects of post-traumatic stress disorder, and that interventions which target the amygdala could therefore be beneficial for sufferers of the condition.

Although earlier studies have provided some evidence of altered fear responses in patients with amygdala damage, this is the first to systematically test the experience of fear in a patient lacking both amygdalae. It has its limitations, however. As the authors point out, SM's brain damage is not limited to the amygdala, so her lack of fear could be due to a combination of damage to this structure, adjacent structures such as the entorhinal cortex and connecting white matter. Furthermore, this is a case study involving a single patient, so it will be important to verify the findings in others with comparable damage.

Feinstein, J. S., et al. (2010). The Human Amygdala and the Induction and Experience of Fear. Curr. Biol. DOI: 10.1016/j.cub.2010.11.042.

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I mean, really?? I'm a scientist, and just reading that even made *my* eyes glaze over. If one thing they're trying to convey is the importance and relevance of the scientist's research to GQ readers, what percentage of the readers are really going to walk away with a deeper understanding of what Dr. Jamieson does by reading that description? It would have been a small thing to ask each participant to submit a layman-friendly version of their research (their "elevator talk" description, for example) for GQ to include.

Finally--one of the "scientists" is Dr. Oz. What is he doing in there? One, I would think he's already well-known enough; why not save that spot for another scientist? Two, yes, I know he's actually done research and published, and is on the faculty at Columbia. Fantastic. He's also a serious woo peddler, who has even featured everyone's favorite "alternative" doc, Joseph Mercola, on his talk show, and discussed how vaccines may be playing a role in autism and allergies (despite mounds of evidence to the contrary). This seems to completely contradict their goal of "research funding as a national priority," since Oz is often (and Mercola is always) highly critical of "mainstream medicine." I really don't understand his inclusion, and think it's to the detriment of the rest of the campaign.

Although at first glance it sounds beneficial, in the end, I would definitely not like to be fearless. Maybe to be a little less fearful, but not completely.

I would not be scared of any person or any thing. That lady is probably not even scared of death. I'm not saying I want the disease just the fearless aspect of it.

You have said that this unfortunate woman suffers from disturbed executive control, but I've yet to find any source that connects this to the amygdala. Of course, there's a lot of ground uncovered in that system (as well as others); could this be something that indicates a role for fear or some other similar emotion in executive control?

Has any other brain damage of note been charted in SM? One might think that there may be some other diffuse problems if there's a chromosomal link involved.

By Evelyn Wolke (not verified) on 17 Dec 2010 #permalink

As far as I know the damage is limited to medial temporal lobe structures, but it could affect other areas because of retrograde degeneration. In this case, emotion seems to be important for executive control with specific regard to social interactions.

Ventrolateral PAG reportedly has heavy input from central nuclei of the amygdalae, and efferents to nuclei controlling fear behaviour/motor output such as bradycardia, hypotension, fainting/freezing/playing dead. Might it be damaged too? Or might one safely assume if these homeostatic behaviours are not triggered it's because the amygdalae can send no signal?

Any chance this will lead to something to help anxiety suffers that live in fear, such as myself? Its been over 30 years now and I sure could use a break from living in fear all the time. I cant even take my son to a ball game or attend any of his school functions. What a dad, eh?

What if she'd been a high-roller stock purchaser for a financial institution, with an above-average IQ, and at least temporarily wealthy? I think you'd never know the condition of her amygdala.

By Marion Delgado (not verified) on 20 Dec 2010 #permalink

I don't know how this disease effects her other wise but I myself personally would not mind being fearless. I would not be scared of any person or any thing. That lady is probably not even scared of death. I'm not saying I want the disease just the fearless aspect of it.

@Bal how can you say you'd personally like to not be scared of anything like this lady. It's debilitating, not being scared of anything takes away your gauge of reality not to mention dangerous on countless levels.

maybe because she has been exposed to considerable fear in her childhood she has developed tolerance to it? is that possible?

I think you'd never know the condition of her amygdala.

By supratall (not verified) on 27 Dec 2010 #permalink

@Bal - you have no idea what you're wishing for. to be completely fearless is nearly a death sentence. Fear is what keeps you from crossing the street while a car is speeding past. amongst countless other things you encounter in your daily life where an ounce of fear keeps you from doing dangerous stuff.

By S. D. Vegas (not verified) on 30 Dec 2010 #permalink

commonsense (intelligent consideration for the well being others and your own body) is what stops you from crossing the street when fear no longer rules. why else do you think you have a neural update for if not to override the blinding instinctual knee-jerk emotional reactions most animals are neurotically and mercilessly governed by. we have an evolving brain like no other animal's. use it's calm intelligence and survive.

Fear is a natural protection. Thus, it is a healthy psychological reaction. The absence of fear is an indication of a serious behavioral abnormality. It only seems to be caused by a mutation in a gene on chromosome 1, which encodes an extracellular matrix protein. This is in fact the result of the invasion of this womanâs wild conscience (anti-conscience) into her conscience. This invasion provokes the neurological disturbances observed in her brain. Studies based on dream therapy reveal that many psychological problems that seem to be originated by neurological factors can be eliminated through psychotherapy.

"Fear is a natural protection" It's a part of human instincts. Fear can provoke human instincts as it will release chemicals and nerve cell responses in the hypothalamus, resulting in accelerate adrenaline flows! so what level of development would SM's human instincts be?