The ‘Fear Centre’ of the Brain

I ran into a wonderfully fascinating article over at io9.com…

How Scientists Discovered the ‘Fear Centre’ of the Brain.

(They’re coming to get you, Barbra)

We all know fear. Not only do we know what it is like for us, we can easily recognize fear in the faces of our friends and loved ones and can even recognize it in the faces of total strangers. It is one of the most common and powerful of emotions and yet, we know almost nothing about fear… or at least the neural underpinnings of fear.

But thanks to the hard work of intrepid neuroscientists, what we do know is where fear lives!

How our brains process fear boils down to two tiny little lumps of neurons; whether you’re a human, a rat, a monkey or a mouse, when it comes to processing fear, the vast majority of research says that the most important parts of your brain are your amygdala, a pair of almond-shaped clusters of neurons sequestered deep within your medial temporal lobes.

(The amygdala… the brain’s almond-shaped Fear Factory)

Scientists experimenting with monkeys in the late 30’s and early 50’s discovered that while removing the entire frontal lobes of the brain, including the amygdala, resulted in dramatic personality changes including the monkeys becoming more tame, less aggressive, becoming hypersexual and developing strong oral fixations – removing only the amygdala led to a disappearance of any fear responses.

Despite questions that the earlier scientists’ surgical techniques may have inadvertently severed other brain connections which could have skewed the findings, later more precise surgical methods proved that the earlier scientists were right and that the amygdala was the brain’s ‘Spook Central.’

OK… now we know where fear is processed. Why is this important? What advantage does it have?

Well, it turns out that like many aspect of life, a key factor is location, location, location. The amygdala is strategically placed near key parts of the brain dealing with important input senses like hearing and vision while its output is close to the hypothalamus which regulates hormones like… adrenaline!

(Eeek! Time to run!)

Yes, adrenaline… the fuel of choice behind the good old ‘fight or flight’ response! Pupils dilate, eyesight improves, hair stands on end, hearing decreases,  heart rate and breathing accelerate, blood vessels constrict, extra clotting agents are released into the bloodstream (helps wounds heal more quickly), digestion system all but shuts off (conserving energy), air passages dilate, time appears to slow down and you get an incredible jolt of energy and power… all in a split second. Adrenaline is how a frightened mom can lift up the side of a car to save her child trapped underneath.

Half of you is scared to death and the other half is ready to kick a monster’s ass. To paraphrase a line from Hellboy… “There are things that go bump in the night… Adrenaline is the one who bumps back.”

So kudos and a tip of the old frontal lobe to the research scientists who have pinpointed our fear centre.

Now if they can only help me get over my Palin-Bachmann phobia!

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Reminder:  I will be away in Toronto for Total Jew Lock Down from this afternoon (Wed. Oct. 19/11) through to Sunday night (Oct. 23/11) in celebration of the Jewish holidays of Shemini Atzeres and Simchas Torah.