The Double-Edged Sword: Forethought, Reasoning and Worry

Friday, March 21, 2014 by Meg   •   Filed under Anxiety


Ever wonder why we stay up all night worrying about a big project or the first day of school? How could just thinking about something make us so anxious? 

Turns out that instead of starting from scratch, Mother Nature tends to use spare parts when developing new systems.The evolution of our brain is no different.

Reduce, reuse, recycle, people. Mother Nature says it's "In".

As improved reasoning systems evolved, new brain structures were superimposed over the old. These distinct layers of the brain have all kinds of neural connections between them that provide us with a heightened sense of consciousness, as well as more effective self-protection mechanisms. But the deep connection between older and newer structures means that higher order thinking also has the ability to trigger the more primitive systems underneath. This can lead to anxiety or panic based on nothing but a thought.

So what are these layers?

Neuroscientist Paul MacLean identified three distinct layers which evolved over time, today referred to as the Triune Brain1.  It's kind of like an onion, at least one with only three layers. A three-layered onion may be a rip-off, but, inside our heads, these three parts possess all the stuff we need to avoid hitting the farmer for providing a sub par product.

Triune Brain Layer One: The Reptilian Brain             

Initially, the brain was composed of the rigid and compulsive reptilian brain structures, commonly referred to as "old brain systems". This primitive brain system is responsible for survival mechanisms including fight or flight and other stress responses. It evokes irritation quickly and triggers physical responses to force the body into immediate action. 

If our brain functioned primarily within this system, cornering a human being would look a lot like cornering a crocodile: all teeth and attack, very little thought. Just outran the neighbor's dog? Thank your reptilian brain for the immediate jolt of hormones and energy needed to flee at supersonic speed. This mechanism would be just as valid if you had decided to punch the animal in the face. 

This is also the area that may be more responsive in those with anxiety issues. Individuals who have panic attacks or anxiety may have more shortcuts from other brain regions to this primitive area. The more stress you are exposed to--particularly early on--the more shortcuts you tend to have to fight or flight. It's like a chemical pathway directly to panic mode that can develop in response to stress and persists later because of actual changes in the way the brain behaves.  

For example, if you grew up in a hut next to a tiger breeding ground, survival means developing a hair-triggered anxiety response. 

Triune Brain Layer Two: Learning and Emotions

On top of the reptilian response system developed the paleo-mammalian brain which regulates emotional states and critical memory functions. This area is particularly useful in triggering value judgements based on past experiences. With this system in place, a cornered human is able to recall past attacks, and which alternatives worked best to survive. 

This is where memory functions work in our favor more so than in many other species. Instead of having simplistic plans of attack, like a fawn playing dead or running, humans are able to embrace higher order reasoning. Which tool would work best as a weapon? Is there a dead end over there that I don't want to run towards? 

In the dog chase scenario, maybe you understand that you can't outrun the douchebag, so instead, you decide to wade into a lake based on the fact that you know your neighbor's dog can't swim. This part of your brain would also let you know it was a bad idea to enter the water if you happened to be chased by a crocodile instead. 

Our ability to remember things can create complications, say, when we find ourselves replaying the dog attack later on. Once you have a shortcut from a memory to the first brain layer, even the smell of the neighbor's dog may push you into a panic state, even if that bastard's in a cage. 

Thanks, layer two.

Triune Brain Layer Three: Friendship

Paul MacLean's brain model has served us well when it comes to understanding human emotional response. Those lower two layers serve quite a few functions, from memory to stress responses. The development of the third layer evolved to hedge our bets further and give us an even better chance of survival.

All the single ladies in the house say, "Hey! Good to see you! Can we be friends for the purposes of overall protection and the innate drive towards cooperative living?"

Socialization is what layer number three is all about.

On top of all those fight or flight (layer number one) and memory recall functions (layer two), primates developed the neo-mammalian region. Sometimes referred to as the primate brain, it is critical to note that in humans, this area is more developed than in our primate counterparts. Within this region, our neocortex specifically sets us apart. The neocortex  is necessary for higher order functioning and cognition. This region was vital in the evolution of our social prowess, especially things like decoding facial responses in others. 

Able to build friendships on the off chance that you'll need them for protective reasons? Thank this region. Also thank this region if your mother-in-law's scowl is enough to get your heart racing. Being socially perceptive is a two-edged sword. It means we can feel it when people around us hate our potato salad...or our guts. 
And there's more. This neo-mammalian region allowed human beings to do more than react physically and immediately using the reptilian brain and recall past choices. It allows us to potentially override reptilian type responses with higher order reasoning. 
With this third layer in place, we are also uniquely able to consider whether alternatives would affect us or our families in the future.

Anticipating the future may be the ultimate reason for worry2. As primatologist Robert Sapolsky would say, it is Why Zebras Don't Get Ulcers.

Unlike zebras, we have the ability to ponder all the things that may go wrong tomorrow, and our stomach responds in kind.

Able to worry about your kid's disappointment on Christmas morning? Did it lead you to shop on Black Friday for sneakers they want? Did you employ higher reasoning and consequential tools to avoid punching someone over the last limited edition Jordan's? 
That might be a bad example. 

While we use all three of these layers to function, identifying triggers to anxiety can be a tricky game from this perspective. Many people have more than one reason to be anxious, and the interaction of these three regions ensures that we are well aware of all of them. The triune brain is one more piece to the anxiety puzzle that may be useful to understand.

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Topic-Relevant Resources

Why Zebras Don't Get Ulcers
Primatologist/biologist Robert Sapolsky on stress and your brain. Good stuff.

Brain Lock: Free Yourself from Obsessive-Compulsive Behavior
Useful information and tools for addressing obsessive or scary thoughts and the behaviors that go with them.

From Panic to Power: Proven Techniques to Calm Your Anxieties, Conquer Your Fears, and Put You in Control of Your Life
Techniques for reducing anxiety and living a happier, healthier life.

Mindsight: The New Science of Personal Transformation
New techniques for mindfully altering the wiring of your own brain, leading to increased happiness.

If you're interested in the way the brain works, this book gives a great neuroscience run down.

When Panic Attacks
Detailed overview of cognitive behavioral techniques for changing negative thought patterns