Fear and the brain reaction.
When the fear is near and the brain reacts: Halloween is fast approaching, so watch out for all things that go bump in the night and scratch with long fingernails at your window!
Famously, Franklin D. Roosevelt in his inaugural address as the 32nd President of the United States of America in March 1933 said that “there is nothing to fear but fear itself….that nameless, unreasoning, unjustified terror which paralyzes needed efforts to convert retreat into advance”. The 32nd POTUS could well have made an excellent neuroscientist, for he touched on factors that explain how the brain perceives threat and creates a sense of fear. As is the case during Halloween which, as children know very well, the things we fear the most are usually not real, and can be concocted from our wildest imaginings. What seems - out the corner of our eye - to be a vicious snake, may turn out to be nothing more than a length of old rope well past its prime. And when hanging off the edge of a mountain, it is not our immediate situation that we fear, but what may happen next (falling off!). Neuroscientists have done a lot of research over the years to identify the brain circuitry of fear. So what can neuroscientists tell us about fear, and how to overcome it when those critters come knocking at the door, looking for tricks or treats?!
Professor Dean Mobbs, at California Institute of Technology and Professor Joseph LeDoux of New York University in the USA are both neuroscientists who have done a huge amount of research into the fear network in the brain. Prof Mobbs wrote a highly cited paper published in the journal Science using virtual reality to mimic a predator with an ability to chase you through a maze, capture you and potentially inflict pain, all while lying in a brain scanner. Prof Mobbs and his team found that as the predator in the virtual reality world got closer, causing the person’s fear and threat to increase, the prefrontal cortex activity of their participants began to turn off, while their brainstem activity began to ramp up. The brainstem, and evolutionarily older midbrain areas, such as the amygdala and hippocampus, are associated with arousal, excitement and impulsivity. So when you see the rope that looks like a snake, or are hanging off the edge of a cliff, or if a little critter knocks on your window or goes bump on the night of Hallow’een, you’ll know that these parts of your brain are probably working on overdrive.
Physiologically, we only have a limited number of responses in the body to fear, and these are preserved across many animals – just look at your cat or dog the next time they are scared and whimpering in the corner, hair standing on end with their tail between their legs. As humans, we don’t have a tail, but the hairs on the back of our neck or arms invariably stand up when we’re afraid, we may sweat, feel rigid and stuck to the spot and we may shake with Elvis Legs! But it’s actually how we consciously evaluate these bodily responses that is key to our feeling afraid, and this provides an optimistic insight into how to overcome fear. For example, we can get similar bodily responses when we are positively excited or see something (or someone) we like, or when we see something we have learned to negatively evaluate (from others or our own experience). However, these bodily responses are always about the same – it is just the stimulus, and therefore the story that we tell ourselves about it that changes.
This insight – knowing that it is rather how we perceive our limited bodily responses to unlimited environmental stimuli (ropes, snakes, sexy film stars, mountain edges, Hallow’een critters!) that causes the fear – helps us to gain control and master our demons. Hallow’een can be fun because – in children and adults alike – we all know that it is likely just somebody nice hiding underneath the costume, pretending to scare us! The same goes for horror movies – they can be fun because real actors are pretending, so that they can stimulate our evolutionarily old midbrains – while we can evaluate that they are simply just actors on a screen. And so we can take this knowledge of ourselves, our bodily responses and our fears one step further. This Hallow’een, try to catch yourself and how your body responds as you turn a corner and are briefly caught off-guard by a makeshift Freddie Kruger with scissor hands! And laugh at yourself as you re-evaluate your initial reaction to your bodily responses. And next time you fear something you think is real – try to re-evaluate it in the same way! If you’re on the end of a rope climbing up a sheer mountain face, no matter what your brain is screaming at you – you are going to be alright! Happy Hallow’een Harfielders!
Dr Samantha Brooks is a UK neuroscientist working with the University of Cape Town, specialising in the neural correlates of impulse control from eating disorders to addiction. For more information on neuroscience at UCT and to contact Samantha, see www.drsamanthabrooks.com.