Atomic Habits: Tiny Changes, Remarkable Results: An Easy & Proven Way to Build Good Habits & Break Bad Ones

HOW LONG DOES IT ACTUALLY TAKE TO FORM A NEW HABIT?

Habit formation is the process by which a behavior becomes progressively more automatic through repetition. The more you repeat an activity, the more the structure of your brain changes to become efficient at that activity. Neuroscientists call this long-term potentiation, which refers to the strengthening of connections between neurons in the brain based on recent patterns of activity. With each repetition, cell-to-cell signaling improves and the neural connections tighten. First described by neuropsychologist Donald Hebb in 1949, this phenomenon is commonly known as Hebb’s Law: “Neurons that fire together wire together.”
Repeating a habit leads to clear physical changes in the brain. In musicians, the cerebellum—critical for physical movements like plucking a guitar string or pulling a violin bow—is larger than it is in nonmusicians.
Mathematicians, meanwhile, have increased gray matter in the inferior parietal lobule, which plays a key role in computation and calculation. Its size is directly correlated with the amount of time spent in the field; the older and more experienced the mathematician, the greater the increase in gray matter.
When scientists analyzed the brains of taxi drivers in London, they found that the hippocampus—a region of the brain involved in spatial memory—was significantly larger in their subjects than in non–taxi drivers. Even more fascinating, the hippocampus decreased in size when a driver retired. Like the muscles of the body responding to regular weight training, particular regions of the brain adapt as they are used and atrophy as they are abandoned.
Of course, the importance of repetition in establishing habits was recognized long before neuroscientists began poking around. In 1860, the English philosopher George H. Lewes noted, “In learning to speak a new language, to play on a musical instrument, or to perform unaccustomed movements, great difficulty is felt, because the channels through which each sensation has to pass have not become established; but no sooner has frequent repetition cut a pathway, than this difficulty vanishes; the actions become so automatic that they can be performed while the mind is
otherwise engaged.” Both common sense and scientific evidence agree: repetition is a form of change.
Each time you repeat an action, you are activating a particular neural circuit associated with that habit. This means that simply putting in your reps is one of the most critical steps you can take to encoding a new habit. It is why the students who took tons of photos improved their skills while those who merely theorized about perfect photos did not. One group engaged in active practice, the other in passive learning. One in action, the other in motion.
All habits follow a similar trajectory from effortful practice to automatic behavior, a process known as automaticity. Automaticity is the ability to perform a behavior without thinking about each step, which occurs when the nonconscious mind takes over.
It looks something like this: