What type of “creatures” are you discussing? That makes a difference. My understanding is that many (and perhaps all) mammals have parts of all three brain layers. The section they may lack is the prefrontal cortex.

Many birds are very bright, as well. Parrots, for example. And recent studies of crows have shown that they “think” and “can make tools to use as tools” and so on, which suggests cerebral function of a fairly high order.

The first functional layer in the human brain is often referred to as the reptilian layer to reflect the sense that reptiles and lizards likely have (or at least function from) primarily the first layer.

My brain’s opinion is that animals and birds may possess a sensory preference, as well. Many people have pets that “talk” to them using sounds; other pets want to be touched or not touched; and some are more visual than others, as well. My little French poodle was very clear about how good she looked after a trip to the groomer and would hold up a front foot so you could notice her toenail polish. Friends told me their hated bows and polish and would chew it off as soon as possible. Hmmm.

Individual animals and birds may also fall along the Extraversion-Ambiversion-Introversion continuum. There are pets that run and hide when strangers come to visit (Introverted), versus those that love to greet strangers before they are even through the door (Extraverts). Most are likely Ambiverts; they may not run and hide or rush up and greet everyone immediately, but they tend to observe a bit and then warm up to the guests or decide they do not want to warm up to them for some reason or other.

The terms extrovert, ambivert, and introvert are simply labels for three differing types of brains. They refer to the types of environments in which differing brains feel most alive and alert. For example, each type or category of brains tends to feel at their most alive, switched on, energetic, and capable when they are in environments that matches the need for stimulation. For example:

• Extroverts: gravitate toward very stimulating environments in which a lot is going on. They may like people and enjoy interacting with large numbers of people or they may be prefer to obtain the stimulation their brains crave by interacting with nature, reading stimulating books, or using equipment (such as doing research or playing games on computers). This includes activities that are high excitement and sometimes high risk.

• Introverts: tend to gravitate toward quieter and relatively low-key environments where they can ponder what they have read or heard or are imagining. They may like people very much but they usually prefer interacting with a small group or with only two or three others at a time. They often like to work alone, at least for part of the time. This includes activities that are low stimulation and typically low risk but that may require high attention.

• Ambiverts: tend to prefer moderately stimulating environments. They can enjoy interacting with others and nature or equipment and then tend to back off for a while and interact with just a few individuals. It involves a type of 50:50 dance with stimulation for a while and then a break from stimulation. This includes activities that are moderate in both excitement, attention, and risk.

Remember that all human brains require sleep and rest and relaxation. Once each brain has received its optimum amount, it tends to gravitate toward the type of environment that matches its need for stimulation. There are differing estimates of the relative percentages of individuals who fall into these categories. Below is an example of one continuum.

Your preferred position on the EAI Continuum is believed to be set at birth. You can move temporarily to nonpreferred positions on the EAI Continuum based on what is required of you at any given time, but you will likely use more energy when functioning at those positions.

In which type of environment do you feel at your best—at your most alive, alert, switched on, energetic, and capable? If you have no idea, there is an EAI Assessment on my website that you can print off and complete free of charge.

Good guess. It could. An extreme extrovert is as different from an extreme introvert as night is from day. PET Scan studies have shown that behavioral differences may result from using different brain pathways that influence where the individual directs his/her focus—internally or externally. Work by Dr. Debra Johnson, for example, has shown that brain blood-flow rates differ in extroverts versus introverts.

Extroverts tend to have lower rates of blood flow to the brain, while introverts tend to have higher rates of blood flow to the brain (which goes along with higher rates of internal stimulation). Here are a couple more examples:

Extreme Extroversion:

• Shorter, fast-acting, and less complicated blood flow patterns involve brain areas related to sensory processing (except for smell), variety and novelty
• Dominant pathway is activated by dopamine, a brain chemical that is implicated in most, if not all, addictive behaviors. Adrenalin, amphetamines, and cocaine can increase dopamine levels)

Extreme Introversion:

• Longer, more complex blood flow patterns involve brain areas related to internal experiences (e.g., planning, pondering, remembering).
• Dominant pathway is activated by acetylcholine, a neurotransmitter that affects one’s alertness and ability to pay attention.

I believe the knowledge you can gain by attending The Brain Program can help you a great deal. All things being equal, you have just described behaviors that represent high extroversion on the one hand and high introversion on the other. We devote an entire session at The Brain Program to the Extroversion-Introversion Continuum and the impact of one’s innate position on this continuum to the expression of a variety of behaviors.

In general, our society does not reward introversion. Because of that, extreme introverts can experience a great deal of pressure to exhibit more extroverted behaviors and can perceive themselves as deficient in some way. They can feel like misfits! Understanding this can help you to understand yourself and your child in a way that honors differences. The relationship between you and your child is what’s most important. Rejecting, shaming, or coercing her to be like her siblings, especially if her innate preferences differ from theirs, could have negative consequences to both of you.

Go figure is right! These individuals may be at very different positions on the E:I Continuum. An extravert can be as different from an introvert as night is from day. You may have one of each.

PET Scans have shown that behavioral differences may result from using different brain pathways that influence where the individual directs his/her focus-internally or externally.

Work by Dr. Debra Johnson, for example, has shown that brain blood-flow rates differ in extraverts versus introverts.

Extraverts tend to have lower rates of blood flow to the brain, while introverts tend to have higher rates of blood flow to the brain (which goes along with higher rates of internal stimulation). Here are a couple more examples:

Extraversion:

• Shorter, fast-acting, and less complicated blood flow patterns involve brain areas related to sensory processing (except for smell), variety and novelty

• Dominant pathway is activated by dopamine, a brain chemical that is implicated in most, if not all, addictive behaviors. Adrenalin, amphetamines, and cocaine have all been found to increase dopamine levels

Introversion:

• Longer, more complex blood flow patterns involve brain areas related to internal experiences (e.g., planning, pondering, remembering).

• Dominant pathway is activated by acetylcholine, a neurotransmitter that affects one’s alertness and ability to pay attention.

In general, our society does not reward introversion. Because of that, extreme introverts can experience a great deal of pressure to exhibit more extraverted behaviors and can perceive themselves as deficient in some way. They can actually feel like misfits! Understanding this can help you to understand your employees in a way that honors their innate differences.

Every brain on the planet is different and continues to become even more unique and different from others as the brain ages. Those who are very extroverted tend to gain energy from being around others and may be returning to an out-of-the-home work environment with pleasure and anticipation. Extreme introverts, if they were not already working remotely or in a private office, would likely be agonizing over losing the quiet aloneness that is key to many creatives processes. The ambiverts, who need some mental stimulation and some protection from too much stimulation, will likely be just fine either way as long as they know what works best for their brain and get that type of environment at least 51 percent of the time.

As an introvert, you will find there will be some worship styles that may be more appealing and comfortable. A 5,000-member charismatic church with loud music and dancing in the aisles may not work well for your brain. That doesn’t mean there is something “wrong” with either you or the congregation. It just means that introverts tend to lean toward observing and pondering more than actively participating.

You didn’t identify a specific denomination, so I cannot comment on that. If it is a Christian organization, you may enjoy reading Adam S. McHugh’s Introverts in the Church: Finding Our Place in an Extroverted Culture. He points out that “introverted seekers need introverted evangelists. It’s not that extroverts can’t communicate the gospel, either verbally or nonverbally, in ways that introverts find appealing, it’s that introverted seekers need to know and see that it’s possible to lead the Christian life as themselves. It’s imperative for them to understand that becoming a Christian is not tantamount with becoming an extrovert.”  

Aligning with a church does not mean you must or even should try to exhibit extroverted behaviors. It’s really impossible to sustain for any length of time and could be not only exhausting but also lead to illness eventually. The Introverted brain likes to observe and ponder. You can develop the skill of observing and yet not ever trying to “keep up” with an extroverted brain. To do this successfully requires that you know your brain bent, make healthy personal decisions about what works for your brain and what does not, and select your activities with care. Extroverts, who gain energy from stimulating environments, can find it a puzzle to understand the introverted brain that finds those same stimulating environments very energy draining to say nothing of stressful! It may be helpful to have a few calm, succinct phrases at the ready, too. Perhaps something like:

• Thank you for the invitation. However, my introverted brain needs a less stimulating environment; or, has had all the stimulation today it can handle.

• That activity would be too exhausting for my brain but I would enjoy doing _______________.

• My brain is more of an observer than a participator.