What the Words Mean
The more profound the subject, the murkier the discussion. There’s a lot of fog and illogic in books, articles, and blogs about the potential relationships among the mind, the brain, and God. In this territory, it’s particularly important to be clear about key terms – like mind, brain, and God.
So – by mind, I mean the information represented by the nervous system (which has its headquarters in the brain – the three pounds of tofu – like tissue between the ears). This information includes incoming signals about the oxygen saturation in the blood and outgoing instructions to the lungs to take a bigger breath, motor sequences for brushing one’s teeth, tendencies toward anxiety, memories of childhood, knowing how to make pancakes, and the feeling of open spacious mindfulness. Most of mind is outside the field of awareness either temporarily or permanently. Conscious experience – sensations, emotions, wants, images, inner language, etc. – is just the tip of the iceberg of mental activity. The nervous system holds information much like a computer hard drive holds the information in a document, song, or picture. Hardware represents software.
Immaterial information is categorically distinct from its material substrate. For example, often the same information (such as Beethoven’s 9th Symphony) can be represented by a variety of suitable material substrates (e.g., sound waves, music score, CD, iPod). Therefore, at one level of analysis, Descartian dualism is correct: information and matter, mind and body, are two different things. Nonetheless – as we will see – at another, higher level of analysis, it is clear that the mind and the nervous system arise interdependently, shaping each other, as one integrated process. (And perhaps at a lower level of analysis – that of quantum phenomena – information and materiality are inextricably woven together; but I’m not going there in this essay!)
Mind, as I define it here, occurs in any creature with a nervous system. Humans have a mind – and so do monkeys, squirrels, lizards, worms, and dust mites. More complex nervous systems can produce more complex minds. But just as there is a spectrum of complexity of the nervous system, from the simplest jellyfish 600 million years ago to a modern human, there is a similar spectrum of complexity in the mind. Or to put it bluntly, there is no categorical distinction between the mind of a millipede and a mathematician. The difference is one of degree, not kind. (And how many mathematicians – or anyone, for that matter – could move dozens of limbs together in undulating harmony?)
By God, I mean a transcendental Something (being, force, ground, mystery, question mark) that is outside the frame of materiality; materiality includes matter and energy since E=mc2, plus dark matter/energy, plus other wild stuff that scientists will discover in the future. God is generally described in two major ways: as an omniscient and omnipotent being “who knows when a sparrow falls,” or as a kind of Ground from and as which everything arises – with many variations on these two view, plus syntheses and divergences.
By definition, while God may intersect or interact with the material universe, it is in some sense other than that universe – otherwise we don’t need another word than “universe.” For example, if someone says that God is the same thing as nature, that begs the question of whether God exists, distinct from nature.
The Interdependent Mind and Brain
Let’s review three facts about the mind and the brain.
First, when your brain changes, your mind changes. Everyday examples include the effects of caffeine, antidepressants, lack of sleep, and having a cold. More extreme examples: concussion, stroke, brain damage, and dementia.Without a brain, you can’t have a mind. The brain is a necessary condition for the mind. And apart from the hypothetical influence of God – which we’ll be discussing further on – the brain is a sufficient condition for the mind. Or more exactly, a proximally sufficient condition for the mind, since the brain intertwines with the nervous system and other bodily systems, which in turn intertwine with nature, both here and now, and over evolutionary time; and as you’ll see in the next paragraph, the brain also depends on the mind.
Second, when your mind changes, your brain changes. Temporary changes include the activation of different neural circuits or regions when you have different kinds of thoughts, feelings, moods, attention, or even sense of self. For example, the anterior (frontal) cingulate cortex gets relatively busy (thus consuming more oxygen) when people meditate; the caudate nucleus in the reward centers of the brain lights up when college students see a photo of their sweetheart; and stressful experiences trigger flows of cortisol into the brain, sensitizing the amygdala (the brain’s alarm bell).
Mental activity also sculpts neural structure, so changes in your mind can lead to lasting changes in your brain. This is learning and memory (as well as lots of other alterations in neural structure below the waterline of conscious awareness): in other words, neuroplasticity, most of which is humdrum, like remembering what you had for breakfast, or getting more skillful at chopsticks with practice.
Examples of neuroplasticity include:
- Meditators have a thicker anterior cingulate cortex and insula (a part of the brain that tracks the internal state of the body); a thicker cortex means more synapses, capillaries (bringing blood), and support cells.
- Cab drivers have a thicker hippocampus (which is central to visual spatial memory) at the end of their training, memorizing the spaghetti snarl of streets in London.
- Pianists have thicker motor cortices in the areas responsible for fine finger movements.