length of time.
Whether a child is an introvert or an extrovert is determined by where her set point falls on the systems that manage energy. Energy can be confusing because it’s constantly in flux. An innie might be well rested and lively one day and, then, if she hasn’t had sufficient recharging time, dragging her wagon the next. This lack of consistency can be really confusing to outies, who are almost always energetic. Introverts are conservers, and they recharge their energy in peace and quiet or by reducing external stimulation. Extroverts are energy spenders; they restore their energy by being out and about, being active, and being around other people.
This energy disparity has a tremendous impact on innies. Everything an innie does in the outside world requires an expenditure of energy. Everything an outie does in the outside world gives himenergy. This one detail makes a gigantic difference in how innies experience going out into the world. It also has a huge impact on how others perceive them.
Introversion and extroversion are not black and white. No one is completely one way or another—we all must function at times on either side of the continuum. But we do have dominant sides established by set points, so, just as all children are either right-or left-handed, right-or left-brained, and right-or left-eyed, we are all introverted or extroverted.
Try the following exercise to make this concept more tangible. Write a paragraph with your nondominant hand. Notice the energy it takes to write this, compared to writing with your dominant hand. Using your dominant hand is effortless; you don’t even have to consciously think about doing it. It’s where you function best and feel the most comfortable. But when you write with your nondominant hand, your penmanship deteriorates. It may even be harder to think. Likewise, using your nondominant foot won’t give you your most accurate kick on the soccer field.
Innie and Outie Reward Routes
“ To find for each person his true character, to differentiate him from all others, means to know him .” — Hermann Hesse
Let’s take a closer look at acetylcholine, the neurotransmitter that dominates for introverts. Acetylcholine triggers the brain’s ability to focus and concentrate deeply for long periods. It slows down the body when it is awake so the brain can concentrate. It can also signal the voluntary muscles to get up and go. Paradoxically, acetylcholine also paralyzes the body when you are asleep and fires up the brain during rapid eye movement (REM) dream sleep. During REM sleep, the brain is even more active than during the day.
“Jolt” and “No Jolt” Juices
Lots of neurotransmitters and other chemicals flow like a river of Jamba Juice through the brain. Each variety of neurotransmitter has a dedicated mission, resulting in different behaviors, thoughts, and emotions.
Neurotransmitters either excite or inhibit a brain cell. When they excite a chain of brain cells, it looks like a row of tumbling dominoes. When they inhibit, they tell the dominoes not to tumble.
These are the most important neurotransmitters and their main assignments:
Acetylcholine says, “Let’s think about it.” This is the superstar of thought, concentration, and voluntary movement. It controls vital activities that govern arousal, attention, awareness, perceptual learning, sleep, and waking. It’s the main neurotransmitter used by innies’ “Put on the Brakes” nervous system. A deficiency of acetylcholine disrupts learning and cognitive function and causes memory loss. Acetylcholine neurons are the first to degenerate in Alzheimer’s disease.
Dopamine says, “If it feels good, do it.” This is one of our most rewarding neurotransmitters. Dopamine regulates movement, pleasure, and action. It is essential for alert awareness, especially the feeling of excitement about something new . It’s the main neurotransmitter for outies, built by the building blocks released by the