The (current) limits of neuroimaging

I confess that I’m one of those neuroscience buffs who overestimate the advances made in this field of study. Rejecting dualism comes with a hazard: you tend to idealise any technology that can potentially prove once and for all that the mind is entirely created by the brain. But my idealism has been tempered with a healthy dose of realism after reading this article - it describes the limits of current neuroscience technology like functional magnetic resonance imaging (fMRI) and shows the dangers of overselling the usefulness of neuroimaging. Conversely, it also touches on the danger of ignoring the contributions of neuroimaging, particularly in disciplines like psychiatry. This paragraph makes it quite clear that psychiatry needs to do some serious house cleaning if it is to remain a credible science.

Neuroimaging research also could completely change how we think about psychiatric disorders by rendering obsolete the idea that using discrete diagnostic categories such as schizophrenia or attention-deficit/hyperactivity disorder (ADHD) provides the best way to understand the underlying disorders. Today, these diagnoses are based on formal criteria, outlined in the American Psychiatric Association’s Diagnostic and Statistical Manual, that specify symptoms for each disorder. But these criteria have no basis in neuroscience. In fact, the psychiatric community has become increasingly concerned that traditional diagnostic categories actually obscure the underlying brain systems and genes that lead to mental health problems. In addition, a growing body of evidence indicates that many psychiatric problems lie on a continuum rather than being discrete disorders, in the same way that hypertension reflects the extreme end of a continuum of blood pressure measurements. Neuroimaging provides us the means to go beyond diagnostic categories to better understand how brain activity relates to psychological dysfunction, whereas using it to “diagnose” classical psychiatric disorders could obscure, rather than illuminate, the true problems.

I’m still a staunch materialist, and all this new information doesn’t suggest that dualism is a valid idea. What it does suggest is that although the field of neuroscience is discovering more and more about how the brain gives rise to consciousness, we shouldn’t attribute discoveries to it that it hasn’t actually made.

HT: Matt O Bee

13.3.12

Harris and Hitchens tag team

These two videos of Sam Harris and Christopher Hitchens are from a discussion organised last year by the Whizin Center for Continuing Education. The topic was about whether or not there was an afterlife (an unprovable speculation either way), with Harris and Hitchens squared off against two rabbis, David Wolpe and Bradley Artson Shavit. It seems like all four men gave a good showing, though I agree more with the atheists’ arguments.

Here’s Harris refuting the dualist idea of the mind, or soul, being somehow separate from the physical brain. We can confidently say that our increasing knowledge of the brain – and its connection to the mind – has discredited dualism. But this is a bitter pill for religious believers to swallow, because it negates one core tenet of their faith: the survival of the mind/soul after death. If human consciousness is entirely generated by the brain, then upon the brain’s destruction, that consciousness ends. Forever.

Harris makes clear the absurdity of the idea that our souls go to an afterlife when we die:

What we’re being asked to consider [by dualists] is that you damage one part of the brain and… something about the mind and subjectivity is lost, you damage another and yet more is lost, and yet if you damage the whole thing at death, we can rise off the brain, with all our faculties intact, recognising Grandma and speaking English.

And here we have Hitchens hitchslapping the creepy practice of religious believers trying to convert dying people.

This statement hits the nail on the head:

If Sam [Harris] and I were to form a corps of people to go around religious hospitals, which is what happens in reverse, and say to people who are lying in pain and say, “Did you say you were Catholic? Well look, you may only have a few days left, but you don’t have to live them as a serf, you know. Just recognise that was all bullshit, that the priests have been cheating you, and I guarantee you’ll feel better”, I don’t think that would be very ethical.

 Ah Hitch, you left us too soon.

21.2.12

This is what your soul looks like

This image was in the August 2011 issue of National Geographic magazine. It shows the “color-coded depiction of routes created by a brain’s neural pathways”, made possible by cutting-edge 3D imaging technology. From the accompanying text:

We like to brag about our gray matter, linking smarts to brain cells. But for neuroscientists, it’s also about white matter, the spaghetti-like tangle of nerve fibers, and the networks that carry information between regions of the brain. Who we are — our memories, thoughts, emotions — derives from these wiring connections. The problem was no devices existed to see and decode the neural maze in live subjects. That’s now changing.

Advances in neuroscience and psychology increasingly prove that our minds – constituted of our memories, thoughts, dreams, emotions, decisions – have a physical basis in our brains. As this knowledge becomes more widely spread and accepted, it will revolutionise the way human beings perceive themselves and others. The ramifications for culture, society, law, religion and politics are immense.

For thousands of years people have, to varying degrees, believed in a soul or self that isn’t bound to the physical body, nevermind the specific lump of matter in our skulls. This dualism is apparent in religion, pop psychology, the cultural products we manufacture, even our language – as when we exhort someone to ‘follow your heart’, meaning to trust their ‘gut’ feeling that is supposedly distinct from their brain-derived thinking. I don’t know about you, but all my heart does is pump blood around my cardiovascular system. I do my feeling with my amygdala and my rationalising with my frontal lobes.

The popular conception of the soul or self is becoming untenable. Like the geocentric universe, bloodletting, bodily humours, phlogiston and much of pre-Darwinian biology, mind-brain dualism will eventually end up in the rubbish bin of false ideas. The only thing keeping it from being immediately thrown out is the ubiquitous triumvirate of social inertia, ignorance, and fear.

Those who still believe in immaterial souls and ghosts in machines are on the wrong side of history.




25.7.11




Image by Van Wedeen

We can’t always trust our brains

Neurologist Steven Novella has written an illuminating post on sleep paralysis. He describes this often frightening experience, then explains its neurobiological causes.

One striking thing about this post (and the comments on it) is how grateful and relieved sufferers of sleep paralysis are once they know and understand the mechanism behind their scary experiences. A lot of people – usually romantic types – accuse science of cruelly taking away their cherished illusions, of robbing life of its mystery by driving away the soft shadows with the harsh, bright light of rationality and knowledge. Yet in the case of sleep paralysis we have a clear example of science giving comfort to people, by reassuring them that they weren’t going mad, or being molested by evil spirits or inquisitive aliens.

Another take-home point from Novella’s post is that our brains are prone to misreading reality, even creating delusions of their own. This is why subjective claims to truth and knowledge made by anyone have to be taken with a pinch of salt. Unless those claims have passed through a rigorous screening process (scientific methodology, fact checking and corroboration, tests), they cannot be vouched for. It’s probably fair to say that gullible people do not adequately appreciate how flawed the human brain is. They assume that the brain and the senses are unfailingly accurate interpreters of the world and its happenings, which biases them towards accepting unproven or far-fetched claims as being plausible, if not true.

Dr Novella said it best:

Our brains are capable of distorting, filtering, and interpreting sensory input, of altering memories and even generating false memories, and of generating false experiences. While it is good enough for everyday activity, our brains have many flaws. We cannot rely upon our memories of our experiences to understand the world, especially when those experiences are unexpected or unusual. We need external verification, objective measurement, and careful recording of data.

In other words – we need science and skepticism to compensate for the flaws and pitfalls of our neurobiology.

12.7.11

What exactly is a person’s ‘true self’?

Person X is usually kind, generous and courteous. But sometimes she can also be mean, petty and boorish. Which description would she regard as representing her ‘true self’? Which one would her family, friends, colleagues and acquaintances consider to be her ‘real’ character?

Now let’s expand on the above. Say that Person X is characteristically kind, generous and courteous. But when she gets drunk, she undergoes a Jekyll and Hyde transformation into a mean, petty and boorish person. So, which version of Person X is her true self?

In the first case, one might say that Person X is a complex combination of both positive and negative traits, though she may prefer to consider the positive traits as her true self while others may choose to focus on her negative qualities. In the second case, there are two possible responses:

1. Person X revealed her true, horrible self when drunkenness made her drop her fake mask of good character.
2. Person X is really a kind, generous and courteous person, since it required something as drastic as getting absolutely pissed in order to change her personality.

This thought experiment presumes that there is such a thing as a ‘true self’. But does such a thing actually exist?

Being and Mental Illness: Does neuroscience undermine existentialism?

Man is condemned to be free; because once thrown into the world, he is responsible for everything he does.

- Jean-Paul Sartre, Being and Nothingness

Freedom. Authenticity. Responsibility. Choice. These concepts form the basis of existentialist philosophy, one that challenges and provokes because it denies people their excuses for the (perhaps disappointing) quality of their lives. While acknowledging the limits, constraints and contingencies that affect the number and type of choices available to a person, existentialist ethics nonetheless declares this axiom: you may not have chosen what type of vehicle to travel in, or its condition, but you are the driver. The journey and the destination are your unavoidable responsibility.

Against immaterialism: A rebuttal of esoteric metaphysics

In his article ‘It’s Immaterial’ (New Humanist magazine, May/June 2010), Hindu Council UK director and trained scientist Jay Lakhani becomes the umpteenth person to attempt the impossible: reconciling unprovable, faith-based religion with testable, evidence-based science. More specifically, it is the ideas of non-theistic esoteric Hinduism that Lakhani puts forward as a replacement for what he scoldingly calls the ‘materialist paradigm’. “It has long seemed to me,” Lakhani writes, “that the paradigm which now needs to be challenged is that of materialism, that worldview that everything and everyone is essentially just a product of little bits of matter.” With this line, Lakhani takes his place amongst the ranks of discontents revolting against the reductionist, secular, Western (and thus automatically disreputable) idea of a purely physical universe governed by discoverable laws.

Is cognitive science the final word?

Who are we? The answer to this question is not only one of the tasks but the task of science.

- Erwin Schrodinger, Science and Humanism, 1951

Would an ever expanding knowledge of how the brain and the mind work culminate in the undisputed victory of natural science in the Science Wars? Although cognitive science covers various disciplines, including a few from the social sciences, its methodology is mainly that of the natural sciences; objective empirical study with the aim of developing predictive, falsifiable theories. Given the speed at which new understanding is acquired on how the physical brain produces non-physical phenomena like thoughts and emotions, cognitive science is becoming ever more indispensable in our ancient quest to know ourselves, as individuals and as a species. Meanwhile, social science is playing catch-up as it finds its ideas continually overturned by some latest discovery in neuroscience or evolutionary psychology. It seems that the more social science tries to emulate the methods of natural science, the more open it leaves itself to criticism or refutation.

Imagining the Self (2)

In chapter nine, The Sensory Room, of Raymond Tallis’s book The Kingdom of Infinite Space, under the subchapter The Mystery of the Head-Room, Tallis devotes a few pages to expounding on his Selfhood. How, he asks, do we account for ‘the fact that there is such a thing as ‘the first person’ – the I, here, now – to which all this variety [of conscious experience] is ultimately referred’?

Like the French philosopher Rene Descartes was roughly 400 years ago, Tallis is both puzzled and amazed by this unique human ability to perceive one’s Self, to know oneself as an ‘I’. And like Descartes, Tallis attributes this special power to something outside the body. He makes what is referred to in some philosophical circles as the Cartesian Error; the Mind (the Self) must be separate from the Body (the brain). Thus Tallis dismisses the claim that the mind is, or comes from, the brain as ‘neuromythology’, an overextension by overconfident neuroscientists.

Without… a unifying ‘I’, the brain or mind would simply be a colloidal suspension of unhaunted modules – which is how the cognitive scientist seems to present it. That is why many neuroscientists deny that there is such a thing as a self. If they can’t find it or conceive of it in neurological terms, it can’t exist.

Imagining the Self (1)

In his book The Kingdom of Infinite Space, Raymond Tallis disparagingly refers to the (scientifically supported) idea that we are our brains as ‘neuromythology’. While I agree with Tallis’s argument that though the brain is a necessary condition for consciousness, it is not a sufficient condition in itself, I think he underestimates the importance of the brain as the seat of consciousness. He is (partially) correct to assert that

Selves require bodies as well as brains, material environments as well as bodies, and societies as well as material environments.

However, this presumes a conventional, organic kind of Self, one shaped by a human body and by a human-centric material environment and society. As a thought experiment, say we hook up a living human brain to a sophisticated piece of machinery, effectively creating a cyborg. One could argue that the cyborg would thus be conscious and so have a Self, but a Self that would be very different to the Self that Tallis argued depended on non-brain factors. The brain remains the prime ingredient, without which we wouldn’t be able to even speak of Selves.

Mechanistic Man

Advances in neurobiological, psychological, computational and cognitive sciences are providing a growing body of evidence in support of the ‘mechanistic man’ idea. Our humanity is increasingly being explained in purely physical and biological terms. Is this a cause for fear or despair? Or is acceptance of the facts the key to our emancipation from centuries of suffering inflicted upon ourselves and others due to ignorance and misinformation? There is a transformative power in the affirmation that we are simply valuation machines of immense biological sophistication. When we surrender our misplaced dependence on transcendent meaning and embrace the implications of mechanistic meaning – influenced by our evolutionary biology and its imperatives – then Necessity, that implacable goddess, loses her power to terrify. Necessity, of the biological, physical and chemical kind, is accepted as the meaning we need.

End the (consciousness) war!

Reason is not the ultimate human faculty lauded by classical philosophy, yet neither is it the 'slave of the passions' as David Hume believed. We must avoid the simple, convenient and false reason-emotion dichotomy that rends apart what is intricately entwined, even interdependent. Neuroscientific evidence shows the important role played by feelings, instinct and the unconscious mind - aspects of our humanity often reviled as inferior to reason and logical thinking - in our personal theatre of life.

Critique of pure Kantianism

I’m reading Clive Hamilton’s latest book, The Freedom Paradox. Its premise, that the freedom of the modern individual to pursue endless consumer choice and sensual gratification has failed to provide ‘inner freedom’, sounded promising enough for me to pick it up. The first few chapters had me nodding my head in agreement as Hamilton dissected the current disappointing state of liberalism in the social, political and economic arena. John Stuart Mill’s ideas on individual liberty were mildly rebuked for his oversimplified views and gushy optimism, though Hamilton acknowledges Mill’s seminal role in the formulation of many liberal values we enjoy today. Hamilton throws water on my fiery Millism, but I could use some cooling down.

Then, at the start of the book’s second act where Hamilton introduces the metaphysical basis of his argument for a ‘post-secular’ ethics, our foregoing relationship, which started out amiably enough, begins to sour. You see, Hamilton turns Kantian.