Hermes and Aphrodite

It’s time for another edition of Comics by People Cleverer Than Me. Enjoy the following introductory XCKD. Click it to embiggen!

Today, I’m going to talk about what exactly it is that we call “me.”

But first – let’s talk about feelings.

Have you ever wondered why the English language has hundreds (if not thousands) of words for precise shades of colors, and comparatively few terms for precise emotions?

Why are we often limited to vague words like “rapport” and “energy” when we talk about the emotion of a conversation? I mean, they’re fine for ordinary conversation, but they don’t tell us much about exactly how it felt. It’s easy enough to say something like, “his lighthearted tone made us all laugh,” but where’s the laconic precision of terms like “dark magenta” and burnt umber?”

Authors often convey emotions with metaphors – “A cold knife twisted in his gut as he heard the dreadful news,” but these kinds of descriptions are more meant to convey a sensation the reader can empathize with – they’re not intended as precise terms for cataloged, objective emotions. I’m not even talking about scientific precision here, necessarily – just enough to provide the listener with a clearly defined idea of what emotion the speaker was feeling.

It seems that emotions often exceed and transcend words. That’s because they affect and involve many more areas of the brain. In fact, they may involve a functional network that’s much older than the one that thinks in words. But I’m getting ahead of myself. First, I’ve got to explain what I mean by “networks.”

While the left and right hemispheres of the brain are physically divided, they’re connected by a bridge of neural fibers known as the corpus callosum (Latin for “tough body”), which allows signals to pass between them. Scientific evidence from functional magnetic resonance imaging (fMRI) research shows that the left and right hemispheres don’t work as separate processors, but as one overall functional unit composed of many subunits heavily dependent on one hemisphere or the other.

The fissures and sulci (ridges) of the brain exhibit some intriguing anatomical non-symmetries between the left and right-hand sides; and some neurophysiological similarities – and differences – have also been identified. Which means there are no exclusively left-brained or right-brained people. However, each hemisphere does seem to specialize in a few particular types of processing.

In an earlier post on connectome hacking, I talked about switching between your mind’s two basic modes of processing: rational vs. experiential; sequential vs. timeless. One of these modes is that of subjective perception of the present moment – full of feelings, sight, and sound; but devoid of interpretation or meaning. The second mode, which can be run in addition to the first, is that of associations – dividing the subjective experience into parts, and placing those parts in a sequence of causes and effects, attaching words to them, and calling up memories to compare them to. By choosing to inhibit the sequential, verbally-oriented components, we can just experience existence.

In my beloved TED video, Dr. Jill Bolte Taylor describes the left hemisphere as a serial processor (one that processes tasks sequentially) and the right hemisphere as a parallel processor (one that processes multiple tasks at the same time). Now, I doubt that Dr. Taylor would be a fan of any neurophysiological theory that treated the left and right hemispheres as independent systems. Still, she does make a convincing case for a somewhat similar idea – that the two hemispheres are semi-independent components of a single system.

When Dr. Taylor suffered a stroke in her left frontal cortex, words, sequential reasoning, and finally even her perception of her own body gave way to an experience detached from physical reality. As she describes it, her subjective consciousness was freed entirely from associations, from sequential planning, and even from subject/object relativity, and simply bathed in awareness itself. It seems she was self-conscious, and yet not conscious of any abstract “self” beyond the present moment and place.

Her journey reveals some intriguing features of consciousness, which is clearly composed of more than just a single self-referential loop of some kind. We can start by looking at the break with external reality that took place in Dr. Taylor’s brain. Between the two types of processes she describes – raw subjective experience, and thoughts about subjective experience – we have a possible (very simplified) model for the basic structure of consciousness. But within this fundamental functional structure, a more complex interplay of communication circuits is at work.

Some scientists are discussing the idea that the brains of human infants come pre-wired with at least five intrinsic connectivity networks (ICNs), each of which utilizes neurocircuitry across both brain hemispheres.

The five networks are specialized, and activity in each one corresponds to a certain type of processing:

1. Sensory (Visual cortex /occipital lobe)
2. Motor (somatosensory / motor cortex)
3. Memory (temporal cortex / auditory)
4. Language/Spatial (depending on lateralization and hemisphere)  (sup. parietal , cerebellum)
5. Cognition (frontal)

Though language processing does involve both sides of the brain, precise speech and verbal “mental chatter” seem to be heavily dependent on the left hemisphere (the right hemisphere is active in language processing, but seems to deal more with the tone and rhythm of speech than the words themselves). Sensory and cognitive processes involve neural networks distributed throughout both hemispheres, and emotions are rooted in even older structures in the lower parts of the brain, like the amygdala and the cingulate cortex. In other words, language is a newer and much more specialized phenomenon than emotions are.

There’s another important difference between emotions and language: we’re able to use precise words for colors because their shades can be measured and quantified fairly easily – they correspond to wavelengths of light. But emotions are more like symphonies – they’re formed through a complex interaction of connectome networks over time, and they can’t be directly perceived (i.e., experienced) by an external observer the way colors in the physical world can. Thus, we describe emotions with words the listener can empathize with, rather than trying to quantify them in any objective sense.

In fact, the more we focus cognitive attention on understanding an emotion rationally, the less attention and processing power is available for feeling that emotion. This is similar to the principle of doing math to stop a panic attack. In fact, it’s a technique used in many meditation schools for dealing with negative feelings.

Now, another intriguing thing about ICNs is that as we age, they continue to grow, change, and interact in new ways. By adulthood, entirely new networks have formed:

  1. Visual – occipital
  2. Sensorimotor -pre-post central gyrus
  3. Auditory/memory – auditory/temporal cortex
  4. Language/spatial – fronto-parietal, strongly lateralized in two hemispheres
  5. SALience (also Known as SAL) Anterior Insula+ anterior cingulate
  6. Balance and co-ordination – cerebellum
  7. Default Mode Network Medial frontal, posterior cingulate, Angular gyrus
  8. Executive Control Network – dorsolateral, prefrontal + superior parietal

Even as the interactions between our ICNs become more complex, our connectomes still manage to sustain a continued sense of self (“ego”) – or at least the subjective illusion of one. The underlying idea here seems to be that the subjective consciousness – that pure awareness that draws heavily on right-hemisphere resources – can focus a “spotlight” or “active grip” of attention on one or more of these networks at any given time, thus causing the subjective self to experience that network’s activity. This is how my subjective self can go from “drifting” in a daydream to being “absorbed” in a conversation to being “focused” on a sequential task.

Meanwhile, all these ICNs are independently active, to some degree or another, during most of our waking hours – but the subjective self’s spotlight can only focus on a certain amount of neural activity at a time. This, the (easy permeable) division between perceived reality, memory, and feelings, and those that are said to be processed by the “subconscious” – i.e., the majority of non-spotlighted nervous processing taking place at any given moment. It’s even possible that some of the networks and sub-networks constitute independent “selves” of their own.

I suspect that some budding neuropshychologists of the ancient world may have had a sense of this idea of specialized networks. In Greek mythology, for instance, Hermes was the gods’ messenger – the god who conveyed information from the gods on Mount Olympus to listeners throughout the world. He was also the god of words, and of symbols. He was known for being a charmer and a schemer – the “silver-tongued” and the “many-cloaked.” Aphrodite was the goddess of love, beauty, eroticism, and sensuality.

These two archetypes provide an intriguing look at the way ancient thinkers classified aspects of the mind – because, after all, what are gods if not reflections and personifications of aspects of ourselves? Now, I’m not suggesting that these two gods each represent a hemisphere of the brain, or a particular ICN. Rather, I think they each reflect certain abilities and attributes of certain functional networks within the brain – not unlike software that can be run on a particular type of hardware.

I’ll get into more of this in future posts. For now, I’ll sign off with this: when words turn back from your thoughts, chances are you’ve stumbled on something worth thinking about.

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