1: It was the early 1990s.  Scientists surgically positioned what looked like “a small joystick and dozens of wires” into the skulls of a group of rats, writes Charles Duhigg in The Power of Habit.

Their goal? To be able to observe in minute detail what was happening inside the brains of rodents.

Each animal was then placed in a T-shaped maze behind a partition with chocolate at one end.  A loud click sounded.  The partition disappeared.  Each rat would usually wander up and down the center aisle and then around the maze.  It could smell the chocolate.  Eventually, most of the animals would discover the reward.  “But there was no discernible pattern in their meanderings. It seemed as if each rat was taking a leisurely, unthinking stroll,” Charles writes.

The brainwaves told a different story.

As each animal appeared to be sauntering around the maze, its brain was working furiously.  “Each time a rat sniffed the air or scratched a wall, its brain exploded with activity, as if analyzing each new scent, sight, and sound.”

The researchers continued the experiment, again and again.  “In time, the rats stopped sniffing corners and making wrong turns.  Instead, they zipped through the maze faster and faster,” Charles notes.

What happened next inside each rat’s brain surprised the scientists?

“As each rat learned how to navigate the maze, its mental activity decreased.  As the route became more and more automatic, each rat started thinking less and less,” Charles writes.  “The rat had internalized how to sprint through the maze to such a degree that it hardly needed to think at all.”

Something else was occurring inside the rat’s brain: The basil ganglia was taking control.  

“This tiny, ancient neurological structure seemed to take over as the rat ran faster and faster and its brain worked less and less,” Charles writes.  “The basal ganglia was central to recalling patterns and acting on them. The basal ganglia, in other words, stored habits even while the rest of the brain went to sleep.”

2: What does all this have to do with how habits form?  


This process—in which the brain converts a sequence of actions into an automatic routine—is known as “chunking,” Charles notes.  “There are dozens—if not hundreds—of behavioral chunks that we rely on every day.  Some are simple: You automatically put toothpaste on your toothbrush before sticking it in your mouth. Some, such as getting dressed or making the kids’ lunch, are a little more complex.”

Others are even more complicated.  Consider backing our car out of the driveway.  At first, this act required tremendous concentration and effort.  Now?  “Our basal ganglia kicks in, identifying the habit we’ve stored in our brains related to backing an automobile into the street.  Once that habit starts unfolding, our gray matter is free to quiet itself or chase other thoughts, which is why we have enough mental capacity to realize that Jimmy forgot his lunchbox inside,” Charles observes.

Habits occur because our brains are constantly looking for ways to save effort.  

Which is a huge advantage for us as human beings.  “An efficient brain also allows us to stop thinking constantly about basic behaviors, such as walking and choosing what to eat, so we can devote mental energy to inventing spears, irrigation systems, and, eventually, airplanes and video games,” comments Charles.

3: The only problem?

Our brains can’t tell the difference between bad and good habits.

Habits are “the choices that all of us deliberately make at some point, and then stop thinking about but continue doing, often every day.

“And though each habit means relatively little on its own, over time, the meals we order, what we say to our kids each night, whether we save or spend, how often we exercise, and the way we organize our thoughts and work routines have enormous impacts on our health, productivity, financial security, and happiness,” Charles writes.

The good news?  

“We now know why habits emerge, how they change, and the science behind their mechanics,” notes Charles.  “Transforming a habit isn’t necessarily easy or quick.  It isn’t always simple.  But it is possible.  And now we understand how.”

More tomorrow.


Reflection: Reflect on the habits that are working for me and those that aren’t working for me.

Action:  Journal about it.  Select a habit I want to change and how I can use the information above to help change it.

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