Cerebral Hemisphere Differences: Pattern Definition

Continuing with a quick post based on observations in The Master and the Emissary by Iain McGilchrist, another example of hemispheral specialisation is illustrated in the image below.

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A typical person will envisage this large S composited with smaller Ss (that could be replaced with any symbols, so there is nothing special about the S comprised of Ss) as represented by the centre image of the rendition of the bilateral interpretations.

Where there is left hemisphere damage, the right would envisage something more like the S on the right—seeing the big picture but losing detail. Where there is right hemisphere damage, the left would perceive something more like the S on the left, which is the detail of the composite Ss without recognising that they composed a bigger picture. This is conveyed in the aphorism of losing the woods for the trees whilst the former right hemisphere dominant view might not realise that the forest has trees.

But even this misses the point slightly because if you are viewing this as a typical person, you can assemble the Ss on the left and realise that it makes a larger S whereas a person with right hemisphere damage will just see a mass of Ss and not see the larger S shape. Moreover, it’s not that the right hemisphere wouldn’t ‘see’ the smaller composite Ss, it just wouldn’t put any significance on them, thus ignoring them and considering them to be background noise.

I really do want to share about the non-stereoscopic animals as well as another instalment from The Matter with Things. At least one of these is probable for the next post.

Cerebral Hemisphere Differences: The Colour and the Shape

One key aspect of left and right hemisphere differences is the notion of identification versus naming and categorisation. I tend to view the right hemisphere as rather Zen. It just sees things as they are without particular care, judgment, or attachment.

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2 Orange Circles as tentatively experienced by the left and right hemispheres of the brain.

I composited a quick illustration to convey the difference. Starting with the right hemisphere, the object is recognised in a global context. Whilst it can be distinguished from a blue thing or a square thing, this is done by holistically surveying the world. The difference is perceived but rather without reflection on memory.

Generally speaking, both hemispheres ‘see’ the object, but where the right hemisphere is interested in the object as presented, the left hemisphere is interested in re-presentation. Where the right hemisphere is about being open to the experience itself, the left closes.

From an evolutionary vantage, the right hemisphere is interested in surveying the world at large and being alert to potential danger or survival queues, perhaps a food source. If the right hemisphere is triggered, the left hemisphere jumps in. This said, the left hemisphere is tightly focused, so if something does alert it—remembering that it is not switched off awaiting the right brain to activate it—, it will respond more quickly than the right hemisphere, though as I’ve noted previously, accuracy is not it’s forte, as the right hemisphere may have to convey that the snake that startled you was, in fact, a garden hose.

The left hemisphere is where categorisation and naming take place. Moreover, it stores the object for later retrieval, creating a map. If a subsequent observation is made, it is compared and contrasted relative to the map. After enough observations are made, the left brain isn’t so interested in observing the external world. It perceives a circle-y shape or perhaps an orangy colour and is convinced (metaphorically) that its cached version is satisfactory.

There is a book named Drawing from the Right Side of the Brain. I don’t want to comment on the book in depth, save to say that the author’s premise is that the so-called left-hemisphere person will look at the face of a subject and draw a generic oval shape. The eyes will be general eye shapes, following the same pattern for the nose and mouth. In the end, they will have rendered a portrait on the level of a child.

Whistler’s Mother, a restoration as reimagined by Mr Bean in the movie Bean.

The artist who inhabits the left brain will instead note the contours, shadows, and colours of the face in front of them. One exercise that I had learned in some art class years before I read this was to draw from an inverted portrait. Not being so common as upright faces, the left brain has no representations modelled and so defers to the right hemisphere that is now looking at the object—the terrain—rather than the model.

Inverted image of Igor Stravinsky, a popular subject for breaking left-brain fixedness

I find the divided hemisphere activity in animals without stereoscopic vision to be fascinating. Perhaps, I’ll comment on this next.


* I am not claiming that the right hemisphere sees the world as fuzzy or hazy. Rather, this was me taking artistic licence to not ascribe strict boundaries to the objects in the world, especially as constrained by language.

Half-Life of Facts

A colleague shared this article, which asks, “Should we really believe scientific facts will last forever when history is full of revolutions in thinking?” I discuss this in a recent post, The Truth about Truth.

The only thing I’ll add is the separate notion of the half-life of knowledge—essentially what we treat as fact will in fact (pun intended) not be true for one or another reason. This article gives the same case I mention, which is the invalid notion of a geocentric world. In some cases, it was true in a particular context, but the context is no longer valid. In other cases, the revision has been one of increased precision or accuracy, perhaps Newtonian versus Einsteinian physics.

Even in the case of tautological facts, things can change and meanings can shift. In the case of the colour spectrum, Newton wanted to mimic the Western musical notion of the octave, so he assigned colour names to the light spectrum when viewed through a prism, but there are two differences between his proclamation and our current understanding.

For one, what he labelled blue, we’d today call cyan. Sure, it’s in the family of blues, but when we think ‘blue’, we aren’t likely imagining cyan.

Moreover, he injected indigo to arrive at the seventh colour note, per the octave. But this was just a shoddy addition made in haste. In fact (there I go again), indigo would likely be named dark blue today.

Operant Chickens

As with chickens, humans can learn through reinforcement AKA operant conditioning.

In this video clip, we see a chicken learning that pecking a red circle yields a payload of food. Yet there is a problem with this algorithm. I don’t expect this study was meant to elucidate this point, but I’ll continue.

Except for one instance where the blue circle was pecked to yield nothing, the chicken learned that packing the red yielded a treat and so became fixed on seeking the red. What the chicken did not explore where the other colours—beige, green, and yellow. Perhaps these might have had a larger payout or a ‘better’ reward. Perhaps even a penalty or punishment, but I’ll ignore that eventuality.

The point is that through operant conditioning, the chicken is habituated. I feel that this is a metaphor for many such habituations in humans. People are indoctrinated (habituated) into all sorts of beliefs and behaviours, from the organisation of social and political systems to economic systems.

When I see people defending Democracy as Churchill did as “the worst form of government, but the best so far,” I can’t help but consider the parallels: Democracy is the red dot; capitalism is the red dot.

This not being a self-help blog, I’ll mention is passing the routines we get ourselves into that are analogous to this chicken—wandering through the world as if with blinders. The difference between a rut and a grave is the depth or dimensions. Are you in a rut on your way to the grave?

This is all I wanted to say. No chickens were harmed during the production of this blog entry.

VIDEO: The Truth about Truth

I wrote about this content in 2019, but I wanted to revisit it for a video as well as create a podcast audio version.

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In today’s segment, I am going to share my perspectives on the truth about truth. To start, I’ll let the audience know that I do not believe in the notion of truth. I feel the term is ill-defined especially in the realm of metaphysics and morality. I feel that when most people employ the word ‘truth’, what they mean to say is ‘fact.’ That a fire engine is red, for example, may be a fact, if indeed the fire engine happens to be red, but it is not true. This is a misapplication of the term. If you employ truth as a direct synonym for fact, then this is not what’s being discussed here, and perhaps your time might be better spent watching some content by the Critical Drinker.   

My argument is that truth is not objective. Rather it is subjective and perspectival. I concede that there may be some objective truth out there somewhere, but it is not and will not ever be accessible to us because of limitations in our sense-perception faculties and cognitive limitations. Per Aristotle, we only have five senses with which we can connect to the world, and these senses are limited. If there is anything out there that would require another sense receptor—a sense receptor not available to us—, we would never be able to sense it, to even know of its existence. Perhaps the universe emits 100 sense signals, but we are only capable of receiving and translating five. We’d be oblivious to 95 per cent of reality.

I am not making any claims that this is the case, but human cognition is so limited, that we can’t even conceive of what another sense might be. If you can, please leave a comment.

To be clear, I am not talking about senses we know other species possess. Bats may have echolocation, and sharks may have electroreception. Some animals may have greater sensory acuity—superior vision and auditory senses, olfactory and gustatory, tactile, or whatever. Some can see into infrared or ultraviolet light spectra. Technology that includes biomimicry provides humans with microscopes for the microworld and telescopes for the macroworld. We have x-rays and sonar and radar, radios and televisions that extend our senses, but these provide no new sensory receptors.

Like the story of the blind people and the elephant, we are left grasping at parts. But even if we are able to step back to view the whole elephant, to hear the elephant, to touch and smell or even taste the elephant, if there is more to the elephant, we cannot know it. The same goes for ourselves.

I know that some people might inject gods or psychic or paranormal energy into this void, and sure, feel free, but I am looking beyond these pedestrian concepts. What else might there be?

But let’s depart this train and head in a different direction. I want us to focus on the senses we do have. For the typical human, sight is our primary arbiter of reality, at least as defined idiomatically. We tend to believe what we see, and what we see, we assume as real—even if we are later mistaken. I guess that wasn’t a unicorn or a pink elephant. I must have been hallucinating or dreaming. I could have sworn that was Auntie Em.

There are several competing theories around truth, but I’ll focus on the Correspondence theory, which is simply put, the notion that, proxying reality for truth, human perception corresponds with the real world. And a pragmatist might argue that’s close enough for the government.

Keep in mind that historically humans have contorted themselves into making calculations. Remember how long people had been tying themselves into knots to show planetary motion in a geocentric system creating epicycles and retrograde motion to map understanding to a perceived reality.

One might even argue that we’ve progressed. It wasn’t true or accurate then, but now it is. And perhaps it is. Let’s look at some illustrations.

NB: Due to an editorial mishap, this paragraph was dropped in the podcast, hence dropped from the video, which shared the podcast audio source. As such, this image was also not used in the video. This is unfortunate, as it was meant to introduce those with limited maths knowledge to the asymptotic curve, as described. Apologies, and I hope this serves to orient any travellers who may have lost their way at this point.

In this first illustration, we see Truth (or relative truthiness) on the Y-axis and Time on the X-Axis. On the top, we see a threshold representing Reality. In the plane, I’ve rendered an asymptotic curve, where over time, we get closer and closer to the Truth. But we never quite get there. More on this later.

The next illustration will help to demonstrate what’s happening.

Notice there is a gap between the curve and the Reality cap. For one thing, we don’t really know where we are relative to Reality. In the case of the geocentric system, we might have been at the leftmost space. Once we determined that the system is actually solar-centric, we might have moved right on the curve to close the gap. We might be tempted to defend that we’ve finally reached the truth, but we’d have been equally willing to make the same defence from the geocentric position, so we need to be mindful of the past.

Perhaps, this last example was too obvious. We feel comfortable staking a truth claim—or at least a claim of fact. So let’s look at another example.

Let’s re-use the same axes—Truth and Time—, but rather than an asymptotic curve, let’s presume something more polynomial in nature—or not particularly cyclic. Rather than retrograde motion in planets, let’s visit the supposed progress of Newtonian over Einsteinian physics.

This takes a bit more setup but bear with me.  In this case, I have taken liberties and illustrated the Einsteinian physics gap to capture an inferior vantage on reality over Newtonian physics. Granted, I need to rely on a bit of suspension of disbelief, but in the bigger picture, I am trying to convey a scenario where some new paradigm puts the prior knowledge in perspective.

In this instance, both Newtonian and Einsteinian flavours of physics are based on a materialistic, particles-based model, which is where the modern physics consensus resides. But, let’s say that consensus changes in such a way that it is determined that something else underlies reality, say consciousness per Analytic Idealism as proposed by Bernardo Kastrup or per Integrated Information Theory (IIT) as advanced by Donald Hoffman and others. As with retrograde motion, we might end up finding that we were barking up the wrong tree. This might be a bit different because the particles are a directly perceived manifestation of the underlying consciousness, but I wanted to create a scenario where knowledge thought to have advanced actually regressed, but this wasn’t revealed until a new perspective was available.

Yet again, an important aspect of note is that we don’t actually know the distance between our perceptions and real Reality.

This last illustration builds upon the first asymptotic chart but has an in-built error margin meant to reflect language insufficiencies. There is some concept that people feel they grasp, but the consensus is not as unified as the group thinks.

I’ll share two examples, the first being the concept of justice. To me, Justice is what I deem a weasel word. It’s a word we commonly use, but it means different things to different people. To me, it’s a euphemism for vengeance by proxy, but for others, it transcends that and mirrors some impartial dispensation of just desert—some good old-fashioned law and order.

[Justice is] a euphemism for vengeance by proxy

Without getting stuck down some rabbit hole, my point is that if we aggregate these beliefs, the asymptotic curve represents an average consensus vantage rather than something as obvious as 2 plus 2 equals 4. On this note, allow me to clear the air.

Some viewers might be clamouring to say, “but 2 plus 2 equals four is true.” But this is tautologically true, which is to say that it’s true by definition. It’s a similar tautology to saying that it’s true that snow is white, or coal is black. We’ve already defined snow, white, coal, and black, so these may be facts, but they are true by definition.

Revisiting the chart, notice that there are two curves in the space. In this case, I illustrate competing truth claims from the perspective of an omniscient narrator. The case is whether the earth is an oblate spheroid or is flat. I am going to go out on a limb and assert the earth is spherical, as represented by the top blue curve—and we have some margin of error as to what that might mean. The bottom red curve depicts the perceived truth of the flat earthers, who also have some room for semantic error.

Given that I am presuming that I am in the right adopting the majority position—please be right—, the blue curve is closer to Reality than the red curve. Of course, in the event that the earth is really flat, then it proves my point that we don’t know where we are relative to truth, so we assume that the state of knowledge at any given time is what’s real.

Again, forgive my fanciful examples. Please don’t tell me that this spheroid versus planer earth is tautological too because you’d be correct, but I am already aware. They are just nonsensical illustrations. Nonetheless, I hope they’ve served to express a point.

I could have as well created curves that depicted two cohorts’ beliefs on the efficacy of tarot or astrology in predicting the future. I am sure that it might render somewhat like the last chart, but I’d also presume that both curves would have very low truth values as seen from an objective observer. Secretly, I hope tarot wins the truth battle.

Before I end our time together, I’d like to convey that for an Analytic Idealist, these charts might be more acceptable at face value. For a Realist, Naïve or otherwise, they may argue that this curve is not asymptotic and may in fact reach some tangency. I don’t happen to believe this is the case or I wouldn’t have spent my time assembling and presenting this. Time will tell. Or will it?

VIDEO: The Problem with Postmodernism

The theme of this Institute of Art and Ideas video is ‘Should we move away from postmodernism?‘

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EDIT: Find my version of this content on YouTube:

Video: Postmodern Defence

At the start, I feel as usual, that the definition of postmodernism is nebulous, and the fora agree, methinks. Toward the end, Hilary Lawson concedes that key actors tied to the early postmodern movement denied being postmoderns, singling out Foucault and Derrida. More on this. Keep reading.

Julian Baggini, the bloke sat on the left and whose positions I am only getting familiar with, starts off the clip. He makes some points, some of which I agree with and others not so much.

He makes a play at claiming that there is some objective truth to be attained, following on with the statement that without this notion, it’s anything goes. I disagree with both of these assertions. Then he cites Thomas Nagel’s The View from Nowhere, wherein he posits that subjectivity and objectivity are extrema on a spectrum and that experience is somewhere in between. This conforms to my beliefs, but there are two provisos. First, the extremum of objective truth is unattainable, objectively speaking. Moreover, as I’ve written before, we have no way of adjudicating whether a given observation is truer than another. It seems that he leaves it that we don’t need to know the absolute truth to know “true enough”, but I think this is both a copout and wrong—but not too wrong for pragmatism to operate.

For example—not mentioned in the clip—, I can imagine that physicists feel that Einsteinian motion physics is truer than Newtonian physics, especially as we need to take measurements nearer to the speed of light. In my thinking, this might provide a better approximation of our notion of the world, but I can also conceive of an Ideal, non-materialistic perspective where both of these are rubbish from the perspective of truth. I feel that people tend to conflate truth with utility.

Julian makes an interesting point about semantics with the claim that “some people” define certain things in such a way as to not possibly be attainable and then claim victory. But what are his three examples? Free will, the self, and objectivity. If you’ve been following me, you’ll know that I might be in his crosshairs because I tend to be in the camp that sees these concepts as sketchy. And to be fair, his claim of defining something in a manner to keep a concept out of bounds is the other side of the same coin as defining something in such a way as to get it into bounds.

The self is different to free will insomuch as it’s a construction. As with any construction, it can exist, but it’s a fiction.

I’ve spoken at length about my position on free will, but I am fairly agnostic and don’t particularly care either way. I feel that the causa sui argument as it applies to human agency is more important in the end. The self is different to free will insomuch as it’s a construction. As with any construction, it can exist, but it’s a fiction. Without interacting with Julian or reading his published works on the self, if there are any, I don’t know how he defines it. And here we are discussing objectivity.

Given Nagel’s objective-subjective polarity, it seems they want to paint postmodernism as claiming that everything is subjective and that science (and religion) hold claims to objectivity. Hilary Lawson, the geezer on the right takes a position between extremes, but he denounces Julian’s claim about objective truth, noting that many people (especially of religious persuasions) make claims on Truth that are diametrically opposed, ostensibly labelling the same object simultaneously black and white. And the object for all intents and purposes is red.

I’ve gotten out of order, but Julie Bindel makes some good points on Feminism and suggests that the philosophical feminists—may I call them pheminists? No? OK then—such as Judith Butler have set women’s rights back by claiming that the category of ‘woman’ is invalid. Minni Salami defended Judith by noting that Butler has helped constructively in some ways and, citing Simone de Beauvoir, that woman is a category established by men to create The Other Sex. Still, Julie—not incorrectly—states that without a category, women (or whatever collective term one decides is representative) cannot be afforded legal protections—because law, as facile as it is, is all about categories and classes.

Hilary reenters the fray and states that it is not acceptable for one person to claim that their lived experience is all that is needed just because that is their truth. To be fair, this feels like a bit of a strawman argument. Perhaps I need to get out more, but I am not familiar with anyone credible making this claim.

I enjoyed watching this clip and processing the information. I hope you do as well. If you have any comments, I’d love to read them.

The Matter with Things: Chapter Five Summary: Apprehension

Index and table of contents

This is my take on the fifth chapter of The Matter with Things. I suggest reviewing the previous chapters before you delve into this one, but I won’t stop you from jumping queue.

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Intro

Chapter five of The Matter with Things is titled Apprehension, following the previous chapters, Attention, Perception, and Judgment. From the start, let’s clarify that apprehension is not meant in the manner of being nervous or apprehensive. It’s meant to pair with comprehension. More on this presently.

Whilst the previous chapters have been heavily focused on the importance of the right hemisphere, this chapter is focused on the left, which may be given the chance to redeem itself. Not surprisingly perhaps, given the relative function of the right hemisphere versus the left, this chapter is much shorter than prior chapters.

Content

This chapter opens by asking what happens to a person who experiences left hemisphere damage. But let’s return to the chapter title. Apprehension is retaken etymologically and means to hold onto or to grasp. This is the function of the left hemisphere. The right hemisphere is about comprehension. The root ‘prehension’ is Latin for hold; the added ap prefix suggests holding on, whilst the com prefix suggests holding together.

Whilst conceptualising and abstract language is a right hemisphere function, spoken words are a left-brain function. It turns out that so is pointing and other gesticulation, reminding me of some ethnic stereotypes of people who speak with their hands. We need to keep in mind that the right hemisphere controls the left part of the body whilst the left hemisphere controls the right. What this means is that the right hand, being guided by the left hemisphere is marching to a different drummer.

Also, keep in mind from the previous chapters that the right hemisphere is holistic whilst the left is atomistic. Where right hemisphere damage is evident, a person has difficulty viewing the parts of a whole, whilst if the damage is on the left, a person has difficulty constructing a whole from its constituent parts. Namely, it may recognise that a body is constructed from an inventory of pieces—head and shoulders, knees, and toes—, but it can’t seem to grasp the cohesive orchestrated picture.

Apart from body continuity, when the left hemisphere is damaged, it might know all of the steps of a given process—McGilchrist shares the example of a person trying to light a smoking pipe—, but there may be difficulty in some of the instrumentation along the way. He cites an example by Czech neurologist, Arnold Pick, which I share here intact:

The patient is given a pipe and brings it correctly to his mouth, then expertly reaches for the tobacco pouch and takes a match from the box but when asked to light it, sticks the head of the match into the mouthpiece and puts the other end in his mouth as if to smoke it. Then he takes it out of his mouth, draws it out of the mouthpiece and sticks the other end of the match in the mouthpiece of the pipe, pulls it out again, holds it for a while in his hand apparently thinking, and then puts it away.

a person when encountering a pencil would feel compelled to grab it and start writing nothing in particular

To underscore the apprehension, where there is damage evident in the right hemisphere, the right hand (under control of the left hemisphere) may just grasp at things for no reason, perhaps reaching arbitrarily out to doorknobs. In one case, a person when encountering a pencil would feel compelled to grab it and start writing nothing in particular. In each case, the right hemisphere was not available to contextualise the experience. This right hemisphere is opening and exploratory whilst the left is closing and instrumental. It seems one might tend to meander without the left to provide a certain will and direction.

McGilchrist makes some correlations between humans and other great apes, but I’ll just mention this in passing.

I am going to pause to editorialise on McGilchrist’s next claim. He argues that Saussure’s claim that language signs are arbitrary is false and gives some examples—sun, bread, and spaghetti—but I am not ready to accept this stance. For now, I am remaining in the camp with Saussure and Wittgenstein that language is both arbitrary and self-referential.  Getting down off my soapbox.  

Recall again that whilst the right hemisphere takes the world as presented, the left hemisphere can only re-present. This is why language symbols are handled by the left hemisphere. Coming back to Saussure, the right-brain experiences a ‘cat’ whilst the left-brain names that object a ‘cat’ and classifies it as a mammal, feline, quadruped, and whatever else.

The right hemisphere is about metaphor, prosody, and pragmatics whilst the left hemisphere, though not exclusively, is about syntax and semantics.

The right hemisphere is about metaphor, prosody, and pragmatics whilst the left hemisphere, though not exclusively, is about syntax and semantics.  The left hemisphere is about symbols. As such, lipreading and interpreting sign language are both left-brain activities.

An interesting conveyance is a case study of a person with left hemisphere damage reading a book who recites the elephant in place of the written word India, so making an association by not recognising the word itself. And there may be a naming problem, so if there was a problem related to an ankle, they would point to an ankle but substitute the name of the part.

Finally, to reiterate the holistic versus atomistic divide, some people with left hemisphere damage can articulate the parts of the body or a bicycle, but when queried can’t relate that the mouth is beneath the nose or some such.

Perspective

To summarise, McGilchrist leaves with a comment, “The fabric of reality typically goes for the most part unaltered when the left hemisphere is suppressed.”

As I’ve been editorialising a bit throughout, I don’t have much to add at this point. Aside from my Saussure nit, I am still very interested in the concept that the right hemisphere constructs reality. I feel that I interpret this construction differently to Iain.

I believe that we agree that there is a world out there, and we interpret this world by interacting with it. Where I feel we differ is that he feels there is a world of objects that we interact with and perceive whilst I believe that we construct this world of objects by means of constructing the underlying material, from particles to fields. I think he’ll discuss this more in later chapters and I could be off base. Time will tell.

Having put Apprehension to bed, next up is a chapter on Emotional Support and Intelligence. I hope you’ll join me.

What are your thoughts? What did you think of this chapter? Were there any surprises? Anything of particular interest?

Leave comments below or on the blog.

The Matter with Things: Chapter Four Summary: Judgment

Index and table of contents

This is my take on the fourth chapter of The Matter with Things. Chapters one and two have been posted previously.

Podcast: Audio rendition of this page content

Intro

Chapter four of The Matter with Things is titled Judgment. Following the previous chapters, Attention and Perception, it’s about how we reach conclusions based on what we perceive.

Trust in left versus right hemisphere processing. The right hemisphere is responsible for anchoring us into reality, so if there are cognitive deficits on the right, the left has a tendency toward delusion.  

Content

This chapter opens with a quotation by Maurice Merleau-Ponty, “Perception is a judgment, but one that is unaware of its reasons, which is as much as to say that the object perceived gives itself as a whole and as a unity before we have grasped its intelligible principle.”

Nearly all delusions are due to right hemisphere damage or dysfunction. Distinguishing delusions, which are distorted reality judgments, from hallucinations, which are distorted perceptions, is to some degree arbitrary, since misperceptions can give rise to misbeliefs, and misbeliefs give rise to misperceptions.

Reinforcing previous chapter content, the right hemisphere is holistic whilst the left is narrowly focused. To borrow the metaphor of McGilchrist’s previous book, the right hemisphere is the master whilst the left is the emissary. The right serves as an anchor to the flighty left.

I’ll share the quote he cites by Orrin Devinsky: The unchecked left hemisphere unleashes a creative narrator from the monitoring of self, memory, and reality by the frontal and right hemisphere areas, leading to excessive and false explanations. Further, the left hemisphere’s cognitive style of categorization, often into dual categories, leads it to invent a duplicate or impostor to resolve conflicting information. Delusions result from right hemisphere lesions. But it is the left hemisphere that is deluded.

This serves as an apt summary. The left jumps to conclusions and seems to need closure, so its first answer is its final answer, no matter how implausible. He cites that this need for closure is also a feature of modernity that seems to insist on closure. This need is evidently amplified in schizophrenics.

Here is where I will take liberties and skip the examples of prosopagnosia, delusional misidentification, paranoia, and the rest, save to inform the reader that clinically speaking paranoia has a broader meaning than used idiomatically. It’s not simply the feeling that someone is watching us or out to get us. It also extends to any number of mistaken references to oneself and includes grandiose and religiose delusions.

Another condition that I’ll pause to mention is that of mirror agnosia, where a subject cannot recognise itself in a mirror, and Cotard’s syndrome where a person believes themselves to be dead.

The right hemisphere supports the body’s schema. Rather contrary to previous mentions that the left hemisphere is the map maker, the right hemisphere seems to contain the blueprint for the assembled body. In fact, children born without limbs may still experience phantom limb sensation due to this mapping.

He writes about the connexion between depression and insight, noting “that depression has repeatedly been shown to be associated with greater realism.” And “the evidence is that this is not because insight makes you depressed, but because, up to a point, being depressed gives you insight.” Moreover, depression is linked to the perception of time.

Next, he touches on false memories and confabulation. Quoting Michael Gazzaniga, he writes, “the left hemisphere generates many false reports. But the right brain does not; it provides a much more veridical account.

Next, he writes about the phenomenon of magical thinking, which is “defined as ‘belief in forms of causation that by convention are invalid’.” The jury is still out on which hemisphere this is more dominant. He tells us that, quote, “Magical thinking may not be pathological at all, except in extreme cases.” And citing Peter Brugger writes that “to be ‘totally “unmagical” is very unhealthy’, and reduces one’s capacity to appreciate value and to take enjoyment in life.” Take this as you may.

In describing the role of reasoning in forming judgments, he clarifies that “reasoning is classically associated with the left hemisphere, but in reality, most studies show that both hemispheres contribute to reasoning; and the part played by the right hemisphere is significant.” Interestingly, if not paradoxically, citing Sass and Pienkos, we learn that ‘The most deluded patients with schizophrenia tend to be those whose thinking is more logical.’ And “Eugène Minkowski’s insight that the problem in psychosis is not loss of reason, but its hypertrophy: ‘The mad person is much less frequently “irrational” than is believed: perhaps, indeed, he is never irrational at all.’”

Discussing inductive and deductive reasoning, the left hemisphere is the whipping boy again. Inductive reasoning needs stasis and normalcy—the domain of the left hemisphere—, so much so that it keeps trying to convince us that everything is normal, so when things like the 2008 financial collapse or Covid-19 come along, the left brain defends ‘Who could have predicted that?” whilst the right hemisphere rolls its proverbial eyes. The right brain is the Sherlock Holmes of deductive reasoning.

Humorously, McGilchrist’s conveys in his words, and I quote, “To put it crudely, the right hemisphere is our bullshit detector” whilst the left hemisphere is a pigeon that is easily duped.

Perspective

To summarise, it’s difficult for me to get past my own conviction that the left hemisphere is an abject wanker. This is the part of the brain always looking for order and reason and constructing patterns where they don’t exist. He doesn’t mention pareidolia or apophenia, but I’m willing to wager that the left hemisphere is responsible for this. I’d also be willing to bet that it is responsible for creating nonsensical categories such as race and gender. It just seems like a half-arsed busybody.

The right hemisphere is responsible for constructing a self or a contiguous self and other assemblages, but I don’t want to lose sight of the implication that these are nonetheless constructions. I don’t prefer the term ‘illusion’, as I am more partial to the notion of ‘fiction’. Our sense of self is a fiction, a confluence of senses. And like the notion of money and so many other fictions, whether countries, nationalities, economies, and so on, this fiction can be useful. But it leaves me wondering what the non-fiction version looks like. I am not saying that the delusional state is perhaps driven by some left hemisphere dominance. This is just a different, perhaps less useful fiction. It seems that some self-less model or slices of selves would be a more truthful rendition, if not notably less practical. I suppose the question might be, “What would life be like in a world where there were no constructed selves?”

Of particular interest to me is the prevalence of so-called mental illnesses and the Age of Enlightenment and the sciences, notably mechanistic thinking.

Now that we’ve covered attention, perception and now judgment, we’ll be covering apprehension in the next chapter.  And heads up, by apprehension he doesn’t mean foreboding, so don’t be apprehensive. I hope you’ll join me.

What are your thoughts? What did you think of this chapter? Were there any surprises? Anything of particular interest?

Leave comments below or on the blog.

The Matter with Things: Chapter Three Summary: Perception

Index and table of contents

In this segment, I continue the journey through Iain McGilchrist’s masterwork, The Matter with Things by summarising chapter three, Perception, a followup to the previous chapters, respectively titled Some Preliminaries and Attention. I strongly recommend that you listen to these in turn, but feel free to play the rebel and cut queue. No one will even notice but you, and if you don’t tell, neither shall I. Come join me.

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Intro

Chapter two of The Matter with Things is titled Perception. Following the previous chapter, Attention, it’s about how we perceive what we attend to. Without attention, there is no perception, but perception is not always correspondent with the so-called reality “out there”.  

Content

From the start, McGilchrist wants to assess which hemisphere is more veridical. Spoiler Alert: It’s the right half. But you already knew that because you’ve been keeping pace. And you also know that I feel he is leaving an option on the table, that neither is veridical to the actual terrain; rather, one just better maps the map. But the question essentially resolves to the same place, not as much verity as trust.

Sensory perception occurs in both hemispheres, but it is better in the right hemisphere than the left, as the left has been somewhat relegated to re-presentation over time—the same hemisphere that is better suited for codifying and mapping using symbolic language—something reserved for the brains of primates—which gives us a virtually inexhaustible way of mapping the world.

Perception is holistic, something better handled by the right hemisphere, being as the left hemisphere is more about focus and specificity. On balance, the right hemisphere is the arbiter of performance delegation, whether to perform a task or delegate it to the left hemisphere. About three-quarters of perception functions are right hemisphere processes.

McGilchrist is partial to the position advanced by Merleau-Ponty, that is “perception as a reciprocal encounter.” Perception is not a passive act. It is an interactive intercourse with the environment. What and how we perceive is affected by our experience and the situation.

Visual Perception

Perception involves all the available senses—and by definition none of those otherwise unavailable. He starts with vision. The right hemisphere does a lot of heavy lifting here. It handles size, shape and pattern recognition, contour, shadows, distance and depth, for example, three-dimensional space, and motion and time as well as the ability to recognise objects from unusual angles or from incomplete information, which I tend to think of as playing some Gestalt role. The right also handles colour perception, though the left maintains the colour name mapping.

The left hemisphere is slightly faster at detection, but if what is detected has any signal degradation, the right hemisphere tends to be more accurate. And since the left hemisphere is, what I’ll call lazy, it may tire quickly and space out, so the right hemisphere may have to intervene, if even a bit more slowly. Paradoxically, if the left hemisphere is given more time, its recognition error rate increases. Incidentally, one reason the right hemisphere may respond more slowly is that it is deliberating to attempt to deliver the correct response whilst the left tosses out its first best guess and declares victory. Nailed it!

Nailed It!

Recall from the last chapter that the left hemisphere is also a master of denial, so it is unapologetic when it guesses wrong. I imagine it signalling ‘that’s not a bus’ just as it hits you and then insists that it never was a bus; that injury must have been caused by something else. Perhaps it was an untoward wrecking ball. 

Without delving into details here, McGilchrist points out that much early research might be invalid because it employed cathode ray tubes—CRTs—whose mechanisms present biased information to the visual field, thereby invalidating conclusions.

the left hemisphere is better at recognising tools—hammers and spanners—, but not musical instruments, which it perceives more as living entities

An interesting area for me is that the left hemisphere is better at recognising tools—hammers and spanners—, but not musical instruments, which it perceives more as living entities. And this is an apt segue to auditory perception.   

Auditory Perception.

Whereas the left hemisphere is better at symbolic language processing and “the processing of meaningless noises, such as clicks”, the right hemisphere pretty much handles the rest, from pitch, inflexion, tone, phrasing, metre and complex rhythm, and melody. The left keeps tabs on basic rhythmic patterns. It is assumed that rhyming relies on both hemispheres working in concert.

For most people, music processing is a right hemisphere event, but this is not true for professional musicians, who utilise both hemispheres, likely owing to the musical language translation processing unnecessary for the casual listener.

Olfactory Perception

Interestingly, the acuity of the nose is orders of magnitude superior to that of the eyes and ears. Olfactory recognition and discrimination have a right hemisphere preference, but emotional reactions to scent may be stronger in the left hemisphere.

Gustatory Perception

“Apart from five very basic tastes – salt, sweet, sour, bitter and umami – which come from the tongue, all flavours come from the olfactory sense.” In general, gustatory perception is a right hemisphere function. However, there is an exception for professional wine tasters, who like professional musicians need to map experiences to words associated to rating and naming.

Tactile Perception

Remembering that the right hemisphere controls the left half of the body, whilst the left hemisphere controls the right, the sense of touch is superior in the left hand. Feelings of warmth, and temperature discriminations in general, are associated with right hemisphere activation. Interoception, the ability to perceive the internal workings of the body, is another right hemisphere process.

Local versus Global Perception

Recall that the right hemisphere captures the world holistically whilst the left hemisphere has a laser focus. This equates respectively to global and local perception. As it happens, the right can do both, but the left is limited to local. This means that if the left hemisphere is damaged, the right can pick up the slack, but if the right hemisphere is damaged, the left cannot compensate for the lost holistic perspective. In practice, the right runs the show and delegates to the left when it deems it to be appropriate for the circumstance. For some reason, normal adolescents have a bias toward local perception over global.

Pathologies of Perception

This leads us to abnormalities, such as Alzheimer’s disease. Deterioration of right hemisphere function leads to a sense of disorganisation and loss of sensation. This hemisphere is also responsible for constructing a sense of self and self-awareness. McGilchrist calls out that the term self has multiple meanings. Much of the notion of self is associated with the medial prefrontal cortex in both hemispheres, but the objectified self and the self as an expression of will (in the respect Schopenhauer spoke of) are left brain aspects.

Perception of a contiguous self over time is a right hemisphere function, the loss of which is not uncommon in cases of schizophrenia.

In discussing visual hallucinations and distortions, almost ninety per cent of these have been attributable to right hemisphere anomalies. McGilchrist shares examples over several pages, but I’ll summarise by description alone of what can be categorised under the umbrella term of metamorphopsia. These might lead to object impermanence, or viewing things as too large or too small, too close or too distant, skewed, or the wrong shape altogether. In some cases, only half of an object, including self-perception, was outsized. This might occur on a macro level or a micro level, which is to say that it may be entire objects or bodies or just faces, or just familiar faces or just eyes or just one eye.  This might occur on a macro level or a micro level, which is to say that it may be entire objects or bodies or just faces, or just familiar faces or just eyes or just one eye.

Some of these cases involved motion, for example, the sense that some object is receding away from the observer as the observer draws nearer to it.

After a journey through Charles Dodgson, AKA Lewis Carroll, and Alice in Wonderland, provides a plethora of examples in prose of some of these visual effects.

From visual hallucinations, we wonder through hallucinations of the other senses, though the data points on these are much sparser, but the left hemisphere does seem to be the culprit of most auditory hallucinations.

Perspective

To summarise, I am again left to feel that the left hemisphere is a deadbeat hanger-on. It’s there in a pinch, but it’s an unreliable narrator and worker that falls asleep at the wheel. Psychology does have a position on what a normal person should see and hear and taste and touch, but normal doesn’t mean real. 

I was hoping to see some information and perspective on synaesthesia, a condition where people perceive experiences through sense-perception organs different to normal. These people see music and hear smells or taste colours and so on. We consider this to be anomalous, but does it provide a fitness benefit, and are these people ahead of “normal” people or are they carrying excess baggage that creates a burden, even if the condition is otherwise benign.

Now that we’ve covered attention and perception, we’ll be covering judgment in the next chapter.  I hope you’ll join me.

What are your thoughts? What did you think of this chapter? Have you experienced or know of anyone who has experienced any of these so-called anomalies. Are you familiar with any of the effects mentioned in Alice in Wonderland? Leave comments below.

Using AI to Decode Speech from Brain Activity

Apologies in advance for sharing PR hype from Meta (formerly known as Facebook),but I want to comment on the essence of the idea, which is using AI to decode speech from brain activity. It seems to imply that one would apply supervised machine learning to train a system to map speech to brain activity as illustrated by the image below.

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To decode speech from noninvasive brain signals, we train a model with contrastive learning to align speech and its corresponding brain activity

The dataset would require the captured patterns of a large enough sample size. In this case, it appears to have been some 417 volunteers.

Activations of wav2vec 2.0 (left) map onto the brain (right) in response to the same speech sounds. The representations of the first layers of this algorithm (cool colours) map onto the early auditory cortex, whereas the deepest layers map onto high-level brain regions (e.g. prefrontal and parietal cortex).

This feels like it could have many commercial, consumer, and industrial uses including removing other human-computer interface devices, notably keyboards, but perhaps even mouses. Yes, I said mouses. Sue me.

Given hypotheses related to language and cognition, I am wondering what can be gleaned by mapping different multiple native language speakers to cognitive processes in order to remap them to speech output if it would be able to arrive at some common grammar that could then output a given thought stream into any known (and mapped) language, allowing for instantaneous “translation”.

Of course, a longer-term goal would be to skip the external devices and interface brain to brain. This sounds rogue science fiction scary, as one might imagine an external device trained on a brain to read its contents. One of the last things this world needs is to have to worry about neuro-rights and about being monitored for thought crimes. Come to think of it, isn’t there already a book on this? Nevermind. Probably not.

Technology is generally not inherently harmful or helpful, as that is determined by use. Humans do seem to tend toward the nefarious. Where do you think this will go? Leave a comment.