Mind Brain Relationships – A/Prof Alan Gijsbers


from Luke’s Journal 2020 | Breath of Life | Vol.25 No.2

The relationship between the mind and the brain is the hard problem in neuroscience. There are many false pictures and inadequate solutions. No one has cracked this problem yet!

Inadequate Solutions

Disneyworld in Florida US presents one such false picture. We are taken into a large auditorium which depicts the inside of the human body, with levers to move limbs, eat, digest, calculate and the like. At the start of the show, an animated figure of a young man wakes up and starts moving the levers. The young man represents the “me” that moves my body. It is cute, but it does not answer the question of how this animated figure lives, moves and perceives inside the body.

Visual perception is another example. Light rays from the outside scene impinge upside down on the retinae of two eyes, travel along the optic nerve, cross over at the optic chiasm, then travel along the visual pathways to the visual cortex where the scene is reproduced stereoscopically on the brain. The scene is superimposed on the visual cortex, but how is that picture actually perceived by the brain? The picture is not just a reproduction of what is seen on a screen seen by me, but I add my own perceptions to the visual cues to create a reality beyond the limits of the screen, a reality that is all around me. I add to this reality with auditory and proprioceptive cues, relating them to memories of previous scenes to interpret how I might respond to this scenario. How does all that occur? That is the hard problem of consciousness.

Mind, Body, Soul

Poor René Descartes, the “I think, therefore I am” guy, is often blamed for the separation of the mind from the brain. In reality, he was grappling with the new mechanistic science developed by Isaac Newton and colleagues, trying to work out how the mechanical body could possibly sustain human reasoning. Descartes tried, unsuccessfully it turns out, to develop his understanding of the world from the single foundational axiom of “I think, therefore I am.” His rationalism was related to his mathematical skill; Cartesian coordinates and all that. He tried to develop a theory of knowledge for all of life in the same way Euclid developed his mathematical axioms.

“Behaviourists have deemed human subjectivity too variable to be assessed scientifically.”

But how can a mechanistic body with its cause and effect reactions within a closed system, relate to the free rational thinking that humans do? Descartes attributed our thinking to our mind or soul, suggesting a disconnect of our soul from our body. However, he acknowledged that the mind does affect the body, and postulated a connection through the pineal gland. His mechanistic approach to the body has been regarded as the start of modern medicine, but in allowing the human body to be treated like a machine, it also allowed the soul to be regarded as a completely separate entity.

The neurologist, Antonio Damasio, blamed Descartes for separating our thinking from our emotions, and his book Descartes’ Error: Emotion, reason, and the human brain cogently argued that our thinking is closely related to our emotions. His postulation was that lesions affecting our emotions also change our thinking. Psychologist and child psychiatrist, Peter Hobson, writing Cradle of Thought: exploring the origins of thinking, observed that children learn to think well in an intact emotional environment. Hobson comments that if computers are to think like humans, they have to develop a social life. Thinking, feeling and socialisation are thus intimately connected. But how do these mind functions relate to our bodies? How do we have these feelings, this subjectivity?

Human Subjectivity And Qualia

Behaviourists have deemed human subjectivity too variable to be assessed scientifically. In response to this, they have tried reducing human behaviour to a simple “stimulus – response interaction”, measuring inputs and outputs. These studies, usually performed with rats, pigeons or other animals, are used to make inferences on human behavioural patterns. While helpful, there are two big problems with the studies. Firstly, while humans might be compared with animals, we are not rats and have significant biological differences. Secondly, humans have an “internal world” that affects our behaviour. This internal world is not just a world that thinks rationally, but it is also comprised of emotions, perceptions and the like.

Neurophilosopher, David Chalmers, coined the term “qualia” to describe our consciousness. Qualia describes our subjectivity – the redness of red and the musicality of music. Yet, is my red-perception the same as your red-perception? We cannot say, for no one else has access to my personal sensations; they can only be inferred from what I describe or from the body language I express. Nevertheless, we all acknowledge qualia to a whole range of external inputs. These qualia, however, are totally private and outside observers have no direct access to them.

This has important implications in clinical practice. Pain, addictive sensations, and other symptoms can only be described by our patients. We have no access to what they are really feeling. We can only make inferences by comparing what they say with how we have perceived these feelings ourselves. This can become very difficult for complex disorders of depression or anxiety. We cannot contradict what another person is feeling, but we need to explore with them how they interpret their feelings.

One of the most challenging qualia is our sense of self. How do I develop the “me-ness” of me; the person who perceives, feels, thinks, and integrates all the different afferent inputs into some sort of coherent whole? The “self” has been dismissed by some as an illusion.

“We cannot contradict what another person is feeling, but we need to explore with them how they interpret their feelings.”

Some Buddhists might think that way, for example. Other people have dismissed the “self” as a social construct, as if that somehow solves the problem of the “meness” of me.

Yet, this thinking is refuted by recognising that there are many social constructs which are still tangibly real. Money is put into a bank to pay bills to enable me to have services. Each of these italicised entities is a social construct but each is still real. It can apply the same thinking to myself. I am Alan, so named by my parents, who registered me at the local town hall in Apeldoorn, Netherlands, where I can get a birth certificate. At school and in a hospital I am identified by my name and date of birth. My identity can be verified further by a photograph, as seen on my driver’s license and passport. There is even facial recognition software now available to identify and distinguish me from impostors who might claim to be me.

Note what has happened. I have moved from a subjective identification of myself to an objective social identification increasingly based on my facial appearance. Another dimension of my sense of self is my biography. This is the story I develop as I live. However, others will have their own version of my life also. We are selective in what we remember, and in how we perceive our memories. My lived experience may alter my perceptions. For example, once I am a parent, I may see my parents’ parenting in a new light. The “self” therefore, has subjective, biographical and physical dimensions to it.

A Biblical Perspective

How does the Bible understand the soul? The Greek word is ψυχη, psyche; from which we get psychology and psychiatry. It could simply mean the essence of a person, the equivalent of the “self”. Thus, the Authorized (King James) Version translates Luke 12:19:

“I will say to my soul, ‘Soul thou hast much goods laid up for many years; take thine ease, eat drink and be merry.’”

In this instance, the soul and the self could be regarded as equivalent. There are other passages which imply a distinction between body and soul such as in Jesus’ comment in Matthew 10:28,

“Do not fear those who kill the body but cannot kill the soul; rather fear him who can destroy both soul and body in hell.” (New Revised Standard Version).

Interestingly someone can kill the body but not the soul, or someone can kill the body and the soul. So is the soul mortal, or immortal? There is, in fact, little justification in Scripture for the immortality of the soul. The Christian doctrine is the resurrection of the body.

This is a profound mystery. The Bible describes humans as made from the earth; Adam from adama, or in Alter’s memorable phrase, humans from humus, a much richer, earthier description than man from dust. Into that earthy form, the Lord breathes his life and the human becomes a living soul (nephesh chaim) (Genesis 2:7). In other words, the living human is a soul, rather than that he has a soul. When breath leaves the body, the person dies. But what happens to the soul? The Bible does not describe the soul living on, but talks about the resurrection of the body. It dies a σωμα ψυχικόν (soma psuchikon, translated “natural body” but uses the Greek word for soul – psyche) and is raised a σῶμα πνευματικόν (soma pneumatikon, a spiritual body, using the Greek word for spirit, pneuma).

There are a number of ways of understanding the time between death and the resurrection of the body. It could be that humans move out of the realm of our time into the timeless realm of eternity. It could be that just as time seems to stand still when we sleep, so time for us stands still from the time we die to the time we are raised. It could be that we are “in the mind of God” between death and resurrection. Any attempt at an explanation is speculative and goes beyond the incomplete Biblical data.

So, are humans best understood as a psychosomatic unity (monism) or a body-soul duality (dualism). There is a third, tripartite view based on 1 Thessalonians 5:23 where Paul prays that the Thessalonians’ spirit, soul and body are kept sound at the coming of the Lord Jesus. It is hard to base a comprehensive anthropology on a by-the-way greeting in a letter, and the debate continues. I am not sure that Biblical anthropology centers itself on compartmentalising humans. However, if we do embrace monism and the resurrection of the body, we still need to explain the mystery of what a spiritual body would be. That again, is to speculate beyond the Biblical data.

“Many neurological syndromes like dementia, stroke, and head injury would suggest that the mind needs an intact brain to function.”

What Can We Conclude?

We might argue that the mind and the body are not quite so separate as Descartes attempted to make them. We have explored the mind side, but what about the body side? Many neurological syndromes like dementia, stroke, and head injury would suggest that the mind needs an intact brain to function. Even though the brain is remarkably neuroplastic, there are limits to the degree in which it can change itself.

Modern neuroscience suggests that the brain is embodied, and that ongoing somatic input is needed to maintain a healthy mind; that the mental side of our function can be changed by pharmacological inputs. Thus, hallucinogens can change our perception of reality; some much older hypotensive agents can make us feel quite depressed; anti-depressants can lift our moods; and addictive agents can stimulate the pleasure centre of the brain and make us feel good. However, simply fiddling with the pharmacological soup in which the brain functions does not guarantee that human problems will be fixed. We can also stimulate the pleasure centre of the brain through addictive behaviours like pokie machines, or through more healthy interventions like meditation and nourishing conversation.

What Then Can We Conclude?

In sum, let’s consider the following conclusions:

• Firstly, the mind and brain are distinct but interactive entities.

• Secondly, mind functions are much more complex than simple thinking, but include perception, emotions and decision-making.

• Thirdly, that one of the mind functions is a sense of “self”.

• Fourthly, that these mind functions can be classified as “soul functions”, but it seems that humans are seen in Scripture as a psychosomatic unity, incorporating interaction between the body and the mind.

• Fifthly, that mind function is affected by brain function, and that brain lesions may affect mental functions.

• Sixthly, that we are embodied beings and that our bodies are God’s gift to us. Furthermore what we do in our bodies has eternal value, for we are judged by what we do.

Finally, as we consider all these points, we as Christians believe in the resurrection of the body, though what this body will be like remains a profound but exciting mystery.

A/Prof Alan Gijsbers (University of Melbourne, Head Addiction Medicine Royal Melbourne Hospital Medical Director Substance Withdrawal Unit, The Melbourne Clinic, President of ISCAST) has a particular interest in a studying neuroscience and theology, the philosophy of the self, and spirituality, topics which underpin his approach to addiction care.

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