The Zoo in Your Head

We all have a zoo in our heads: our brains. Inside lives a monkey, a mouse, and a snake. The monkey or primate brain is what we think of when we think of the brain. It’s the spongy stuff on top. The snake or reptile (sometimes called the R-complex), caps the central nervous system (the spinal cord). Everything in-between is the mouse or the mammalian brain.

The primate brain performs complex calculations such as dexterous motions, subtle distinctions of light and sound patters, symbolic language, in-depth planning, imagination, logical reductions of nested causes with multiple effects of varying potentials, temporal conjecture, and any number of exercises in reasoning that basically tells us to what to avoid in the pursuit of what we want. It’s the ultimate semaphore, the big, red stop-sign. When all the other brains tell you to go, this is the last chance to stop before hurdling the wall of sanity. Although this brain has access to the whole, it is often the first ignored. 

The mammalian brain forms our likes and dislikes. Intense emotions, social status, and egotistical aims are its wheelhouse. It is far too easy to spend far too much time secluded in the world of mammalian sensation. Yesteryear is trimmed with silver linings and gilded in gold; on the other hand, bloodcurdling hate has no better home. Soundbites construct the strings of cause and effect. Jealousy, intimacy, fun, affection, disgust, fraternity, jingoism, primitive justice, admiration, status, blind hope, and community are all examples of mammalian feelings. Minimal thought stirs deep emotion; attachment is key. Mammals make great friends and passionate enemies.

The mammal’s primary preoccupation lies within our social position, our rung on the ladder. One’s place in society influences one’s physical health both short term (how you feel about your boss’s frowning face) as well as long term (how are your ideas received, how are your choices respected, are you valued as a person and employee). The hormonal cocktail of social status soaks the brain in either a toxic sludge or a tonic elixir. How we see our place in the social hierarchy determines how fast we age, how often we get sick, and how well we sleep. This complex of neurons responsible for complex emotion and specific memory is present in all mammals, including dogs, cats, and even rats. They all have the same feelings as us. But not all are equipped with a large primate structure to mull them over in the language of thought, eventually ameliorating them with the wisdom of planning.   

The reptilian brain is the base. It’s the on switch. It keeps us digesting, breathing, and our hearts beating. It keeps us safe. It’s responsible for our reactions to fear, hate, and lust. It loves mindless ritual and endless calm. It is one big analog switch of arousal. It governs our two autonomic nervous systems: parasympathetic and sympathetic. They work in tandem. If one is on, the other is off. One regulates digestion; the other, stimulation. One is meant to be turned on most of the time; the other, only when the time comes. The parasympathetic system promotes homeostasis or the state of healthy repair; the sympathetic puts that process on hold in order to act now. Together, they handle the six Fs: friendship, fostering, food, fight, flight, and fornication. The reptile sees peace as a fortress. The distinction of friend from foe or food fills every encounter.

Two more brains exist, but not in your head; they are in your body. Massive bundles of neurons create a mosaic of intelligence throughout your heart and digestive tract. Heartache and gut-feelings are not just metaphors but the roots, supporting our tree of life. They can override the whole with a single beat of the heart or turn of the stomach as illness teaches us all. When they are not overshadowing our minds with absolute attention, they work mostly in secret along side the reptile to keep us vertical when awake and dreaming when horizontal.