By Dr Samantha J. Brooks Ph.D.
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.
