The brain is the most fascinating organ of the body. The purpose of the rest of the body would be to nourish and keep it alive; and the brain in turn deals with the world in a manner most astonishing. David Eagleman captures the brain and its accompaniment, the mind, in a manner which any English knowing person can understand. To bring the most complicated brain science and its wonders into plain language is an achievement which very few science writers have been able to achieve.
Consciousness (defined here as awareness of the waking state) plays a very minor role in the daily routine of life. We would like to believe that we are in control, but the fact is, we are not. Many things which we do as a routine, including the ability of athletes and musicians, happens totally at a sub-conscious level, and this is a good thing too. The moment we try to analyse our routine actions, like driving, from a conscious perspective, it becomes impossible. Sophisticated motor acts also do not need conscious input, because thinking while ducking a falling branch or side-stepping a speeding car might risk your life.
The traditional view of perceiving by the brain is that sensory data flow from the periphery through the sense organs and its related nerves to the corresponding cortex of the brain. The brain then interprets a sensation, visual or auditory for example. The view is grossly incorrect. The brain is a highly closed system and runs on its internally generated activity. The external sensory data merely modulates the internal sensory data. The author says, ‘In the awake state, the visual and auditory data merely anchors the perception already generated in the brain. Dreaming is cortical activity that is not tied to anything in the outside world; waking perception is dreaming with a little more commitment to what is in front of the eyes.’ The reality in front of our eyes is a complete unknown to us. The brain constructs a view of the reality depending on its sense organs. This reality as conceived by the brain is useful in the physical and social survival of the living being. Our vision, concepts of space and even time are only mental constructs of the brain. The brain has its own generational activity and it takes from the world only what it needs to know. Most of the activities we do have no conscious awareness. They happen at an automatic sub-conscious level.
‘Umwelt’ is the term for the part of the surrounding world or reality one can see and interact with; and ‘umgebung’ is the bigger reality which is around us and which we can never know. Each animal and person having a brain has its own umwelt. In such a view, the brain instead of passively recording the reality is actively creating it. The author takes the example of synaesthesia, where in about one in hundred, there is an increased cross talk between the various sensory regions. This results in an experience of ‘sensory blending’ where one may hear colours, taste shapes, or may relate parts of the body to specific numbers, dates, and months of the year. Synesthetics create their own reality which is different from other humans. However, they accept their version of reality like you do; and believe that your version of reality is strange as you believe about theirs. Reality is indeed an individual perspective.
There is a large gap between knowledge and awareness, the author says. There is an ‘implicit’ memory where the brain holds knowledge of something to which the mind cannot completely access. The examples of this are: riding a bicycle, tying a shoelace, driving a car. The actions happen easily without knowing exactly how they are being done. In fact, trying to analyse such actions might confuse the mind. The ‘explicit’ memory at the superficial level of consciousness is separate from the implicit memory and in some brain conditions, one can be damaged with the other being spared. Some of the implications of implicit biases stored in the hidden depths can give troubling results in the laboratories. It has been shown that racial, religious, and gender biases can be deeply hidden in the implicit regions of the brain and can be brought to the fore by some careful tests. Luckily, the courts do not accept them yet, because that would open a Pandora’s box. Each one of us have some hidden biases which are never expressed in the social world; and one would not want to be exposed on such issues.
‘Implicit egotism’ is an unconscious self-love, or a comfort level with familiar things. It is a powerful emotion driving the brain and it influences the choices a person makes. This might include the products a person buys or the choices for a life-partner. People tend to love other people sharing the same initial as has been proved from marriage records. Implicit egotism goes beyond names-it might even lead you to like an unpopular person if he or she happens to share your birthday. The author says that we are influenced by drives which we would never have believed had not the statistics laid them bare. The implicit systems work in some bizarre ways and it might be responsible for the hunches and the gut feelings one has while making decisions. The knowledge stored in the implicit memory systems helps in making decisions and this is manifested by way of a ‘gut-feeling’ or a ‘sixth-sense’ in popular terms.
So where does this all leave conscious awareness? It is a long-term planner or the CEO of a large organization. The consciousness does not run the day-to-day operations or take the minute-to-minute decisions. However, it sets the goals, and the rest of the system learns to meet them. One of the most amazing features of brains-especially humans, is its flexibility. The neural circuitry with plenty of feed-backing loops both in a backward and forward fashion allows the human brain to be immensely flexible; and this intelligence has allowed so many fantastic discoveries and inventions making our lives easier.
The brain has a capacity to burn tasks of any kind into its neural circuitry. This important tactic allows two things for survival-speed and energy efficiency. A professional tennis player cannot approach a ball flying at ninety miles an hour analyzing whether to use a forehand or a backhand lift. It must happen automatically. This is called ‘burning a task’ into the neural circuitry. The same things happen when a chess champion makes his moves. If the energy expended is like that of a beginner, the chess champion would incinerate his brain in very few moves. This trick of burning tasks is fundamental to how brains run.
The brain machinery burns at the basic level our deepest thoughts and wants we have, and can have too. Our concepts of beauty, symmetry, ideas of fidelity, parental bondage, our tastes of food choices seem natural, but they are the result of billions of years of evolution which allows all the so-called instincts. Instincts are pre-bundled software and they are inherited. However, these have come about by natural selection and evolutionary pressures for survival. Instincts are different from automatized behaviours like typing or riding a two-wheeler because the latter are learnt in a lifetime and the former are inherited. The simplest of our acts are in fact the most complicated and the most evolved. This is precisely the reason Artificial Intelligence is stuck at some level. The AI could deal with fact driven knowledge, but it became difficult to handle simple problems like walking on a crowded street, or understanding a joke. The more natural and effortless something seems, the more complicated is the underlying machinery.
He then fascinatingly describes the conflicting and sometimes warring zones of the brain which decide our behaviour. There are multiple players inside the brain circuits just like the parties in a democracy having varied opinions, but all for the good of the country. He simplifies them into the ‘emotional’ brain and the ‘reasoning’ brain. The emotional brain is deeply hidden in the sub-systems of the brain; and is fast, automatic, intuitive, reactive, and impulsive. On the other hand, the reasoning brain is slow, cognitive, conscious, systematic, deliberate, analytic, and reflective. These two systems are battling it out, as the author says, on a continual basis. Most of the days work is carried out in the automatic system. We rarely notice anything on the way to our office unless something unusual turns up. Slow deliberation for every action would be a waste of energy and does not make sense in evolutionary terms. The rational system cares about the analysis of things in the outside world; the emotional system watches the internal state. The emotional systems rank and prioritizes options in the world-to eat the cake or not is the question- and the rational system helps us to do algebra or calculus. Choices about our actions also happen by the emotional system. Many of the ethical dilemmas we face is due to a conflict between the two.
Similarly, the right and the left-brain hemispheres are semi-independent units and they can be involved at some other levels of decision making in the brain. Brain split surgeries have shown this to be true. The point which the author makes is that our brains have multitudes of levels which guide our final behaviour. There is a difficulty in pin-pointing a single person making the decisions. In another example, he tells about the hippocampus and the amygdala regions of the brain storing the memory of the same event in different forms. The hippocampus handles storing and cementing the memories in the regular fashion; but the amygdala stores memory of the frightening episodes of life and is responsible for the ‘flashbulb’ popping up of old memories.
Biology rarely rests with a single solution; the author makes a strong point. It ceaselessly reinvents solutions, and this puts it apart from Artificial Intelligence where the programmer moves on after finding a solution. There is no concept of reinventing a solution as there are no head programmers in the biological brains. This is another reason AI seems to be stuck. The brain is characterized by a highly overlapping system of solutions which is what the author calls a team-of-rivals architecture.Conscious awareness, the author stresses repeatedly, is like the CEO of an organization helping the overall guiding of the brain. It comes into play when events in the world violate the expectations and the smooth running of the automatic zombie subroutines are challenged. Consciousness then comes into play to direct the specific area to form a response. It is an amazing model. And the author convinces the reader in clear terms. Consciousness is present in animals too, the author feels; and says that consciousness is not an all-or-none phenomenon but comes in degrees. Also, an animal’s degree of consciousness will parallel its intellectual ability. The more automatic subroutines an animal has, the more it will need the ‘consciousness CEO’ to lead and unite the organization. ‘A useful index of consciousness is the capacity to successfully mediate conflicting zombie systems,’ summarizes the author.
Secrets are interestingly dealt with in this new model of rivalry. Keeping a secret too long is harmful for the brain. Revealing the secret can harm relations with a close person or the community leading to emotional upheaval. Hence, there is a tendency of humans to reveal secrets to a total stranger, while travelling for example, to release the stress, yet allowing to keep close relations intact. The section on secrets was fascinating, to say the least.
Free will seems to be an illusion. However, it should not matter in law, says the author in the final part of the book. Our behaviour is the product of our biology. Our genes play a key role in deciding our character, which in turn is the outcome of billions of years of evolution. The exposure of toxins to the growing foetus in the womb, the early childhood experiences, the education, the environmental exposures, the balance of neurotransmitters in the brain, along with genes come together as the final determinants of our behaviour. The author raises a very important question on the implications of this in crime and punishment. Blameworthiness is something which the courts look at in punishing a criminal, and the author argues that this is not relevant. The courts cannot know the full state of the criminal mind to decide the punishment. A tumour pressing on a key area in the brain might lead a man to mass murder or deviant sexual practices. In such proven cases, the present-day courts consider the accused as not guilty. However, in a clear majority, the judge can never know what abnormalities in the brain might have led to a crime. The potential to rehabilitate the criminal and the likelihood of the person to repeat the crime might be better criteria to decide the quantum of punishment by the courts. Brain science can help the courts in deciding this. A crime committed during sleep-walking is no crime; and a crime is punished differently if done in the waking state. Intentionality is important in the courts; however, the author says that our behaviour is an outcome of our sub-conscious state of mind on which the conscious state has little control. What we do and say is the result of the huge iceberg of the sub-conscious state and our conscious thinking is only the tip of that iceberg, playing a minor role.
The author finally ends speculating on the reductionist materialistic approach to the workings of the brain. The reductionist approach wants to study the workings of the brain by studying the individual neurons and molecules inside the brain. The final product called ‘us’ is steered finally by a ‘biological cocktail’ to which we have neither immediate access nor direct acquaintance. The neurotransmitters like dopamine and serotonin, hormones, viruses, genes, and a host of other biological factors control the brain as has been seen by elegant experiments and clinical material. This has led to a one-to-one mapping of the brain regions and behaviours with strengthening of the reductionist approach.
However, the author tends to disagree on this. He believes in the phenomenon of ‘emergence’ which says that combination of simpler things gives rise to more complex things; or the whole is greater than the sum of its parts. The break-it-in-the smallest-pieces approach may not really work in understanding the brain. The study of individual neurons will not be enough. Anyway, the billions of neurons, each having some 10,000 connections to surrounding neurons may never be reproduced in the labs or simulated on a computer. At least, not soon. The brain is not the only deciding biological player. The brain is tied inextricably to the endocrine and the immune systems, which in turn is highly linked to the chemical environments like nutrition, air pollutants, and so on. And finally, there is a complex social network that changes the biology with each interaction. Who exactly is ‘you’? Very difficult to decide. The final subjective feeling of a single ‘I’ may not arise from these huge interplaying symphonies of the brain. There was a huge fanfare when the Human Genome Project finished with decoding of entire human DNA. Unfortunately, it did not tell us much about us in terms of health, disease, and bodily functions. The ultimate recipe book of humans was no different from other animals like frogs or worms. In fact, some lowly species carried more genes than us! So, reductionism in brain science may not work.
The exploration of the inner space by humans in recent times is like the computer turning its eye inwards to explore its own interior. We stand amazed at the brilliance and complexity of the human brain. This equals the complexity and wonder of outer cosmos. The future holds a huge promise in neuroscience as new questions will be continuously asked and answered. The author needs to be complimented for bringing the most complex subject into the plainest of plain English which a high school student can understand.This is the greatest achievement of the author. And when one is turning the pages of a science book like a mystery thriller, you know the book is a winner all the way.
RANDOM MUSINGS 