General Bookthoughts:

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1 The Emerging Mind Category: Brain Science Vilayanur Ramachandran (VR) This Bookthought is by Thoughtpiece.com, editor RM, done in 2009 based on the paperback published 2003 General Bookthoughts: These are the Reith lectures given by VR in They were started in 1948, with the first lecturer being none other than Bertrand Russell. As you would expect, the list that followed is distinguished. These lectures are designed to increase public awareness of science, from what I understand. VR is a passionate and interesting speaker and these written lectures convey these qualities in abundance. For some reason I thought the style was very similar to Feynman candid, easy to read and made me feel all the smarter for it. There is a flattery that you feel as a reader. The core subject is the brain and how disorders can give pointers as to how a healthy brain functions. It is highly recommended. About this document: Thoughtpiece.com is a website run by passionate readers. These bookthoughts are a combination of what we consider the original author s message to be, with some original comments or questions of our own. There are times where it makes more sense to copy the original author s text verbatim, in which instances we use inverted commas to highlight them. These bookthoughts are in bullet point form, with emphasis on content rather than on perfecting the prose. Whilst our goal is to extract the key messages of each book as accurately as we can, we recognise that, on occasion, we may interpret the original author s message inaccurately. We hope that you will let us know of any such errors by visiting the feedback section of our website on and we will endeavour to correct them promptly. Happy Reading!

2 Specific Bookthoughts: - VR makes the point that many breakthroughs in neuroscience are from the study of an individual with a disorder. The sample size, initially, is one. From this, a hypothesis is developed and, after further testing (and possibly a sample extension), a syndrome is named. Examples being the major aphasias, amnesia, colour blindness, blind sight, split brain syndrome etc. VR could not think of one major breakthrough that did not happen on this basis. Contrast this with other spheres of science where massive samples are needed to assess the viability of a hypothesis. We are reminded that for something to be considered a theory, or to enter mainstream science, it must fulfil a few criteria: it must be observable, it must be repeatable under controlled conditions, there must be an explanation for the outcome, and it must be significant. - The Freudian idea of unconscious behaviour is discussed. Clearly our unconscious governs us in so many ways. It throws open the question of who is in charge of whom? Freud, of course, took this one step further by suggesting our unconscious guides us and that our lives are an elaborate post hoc rationalisation of things you already do for other reasons. - Neuroscience gains a lot of insight by studying the brains of patients with disorders. In particular it helps explain how a healthy brain works. - It is heartening that VR looks to evolution to explain how the brain works. - The brain has 100 billion nerve cells (called neurons), each with between 1000 and 10,000 connections with eachother, called synapses. Picture from - Each hemisphere of the brain has four main lobes: frontal lobes are concerned with enigmantic aspects like moral sense, intellect, other behaviour like ambition; the parietal lobe help create a three dimensional spatial representation of the outside world (and your body within it); the temporal lobe manages hearing, emotions and some parts of vision; the occipital love manages vision.

3 Picture from University of Manitoba. - The brain operates as a collection of different functions. If there is damage to one part of the brain, there is no across the board damage. Instead, it is localised. - The fusiform gyrus deals with face recognition. Once a face is recognised, the signal is sent to the amygdala for an emotional response (which would be different for a lion or your spouse). Both are important in recognising faces. Patients with a functioning fusiform gyrus, but with broken wiring to the amygdala, will recognise a person like a spouse as someone who looks like them, but is considered an imposter (the emotional feedback is not there, so this tells the person that it cannot be the spouse). Interestingly, they would immediately recognise the person from their voice, say by telephone (no delusion occurs). - A funny story is relayed about Lord Nelson who had a phantom limb. He argued that, by analogy, that if someone died they could have a soul. - VR has witnessed a lot of plasticity in the adult brain the ability to change and adapt. - He mentions patients with learned paralysis. These are patients who typically suffered nerve damage in a limb (e.g., the arm was paralysed and in pain) and then had the arm amputated. Somehow the pain carried over into the phantom arm, after amputation. So, the pain should not be present in the limb because the limb is no longer there, but somehow the brain carries on believing it is there and is painful. VR very cleverly used the mirror experiment to help such patients. These patients saw their healthy arm in the mirror, but because the view is inverted, it looked like the phantom arm. When the brain saw it as a healthy, moving arm, the pain went away! The visual feedback seemed to be an important message in curing the pain. - Syneshthetes, also discussed in Musicophilia, is a mingling of the senses. It has been established that such people are not crazy. They would be presented with a board of 2 s and 5 s mixed up

4 that a non synesthete would struggle to quickly differentiate. But a synesthete who sees a 5 as purple can quickly discern the difference (the number/colour Synesthesia is the most common). It is a wiring problem in the brain the wiring for the number 5 is touching the wiring for the colour purple. Interestingly, the Roman numeral (V) would not be purple. Synesthesia also seems to be genetic. - VR discusses the evolutionary roots of laughter and suggests it could be nature s way of telling our social group that everything is fine. - The insular cortex receives pain signals from the skin and the viscera (viscera are internal organs). This is then routed via the emotional centres and a pain response is delivered (like agony!). Some patients appear to have the signal to the emotional centres cut, thereby inducing laughter when they should be in pain. Everything is OK, but actually is not. - There are thirty different areas in our visual cortex that helps us to see. VR points out that it is unclear why there are thirty, not one. There is also the old system and the new system. The new system is what we experience as a clear picture. The old system has basic vision changes in light etc and covers the spatial aspects (locating something that you can reach out for). This seems to be subconscious activity (old system). The old pathway still works on patients where the new pathways are severed. Patients can locate movement, but cannot explain how (it is subconscious). They actually think they cannot locate movement, but tests show that they can. The converse also happens. Patients with damage to the left parietal lobe can no longer create a visual spatial representation of the left side. People with damage (in the old system) no longer reach out or move their eyes towards an object even if it is coming towards him dangerously. He is not blind to it, but simply indifferent. They will only eat food from the right side of the plate, put make up on the right side only etc. - VR, as usual, takes this blindsight further. He asks why any of our functions are conscious. He suggests drawing two lists, one with unconscious functions, the other with conscious and then comparing the lists and drawing conclusions on this question. - Mirror neurons are also discussed. VR indicates their important in human culture the process involving copying of teachers, parents, elders, peers etc where we acquire critical skills. He suggests this system may be flawed in autistic children. This makes sense given they cannot empathise. - There is a chapter on art and why it is something we enjoy. He uses the well known experiment on herring gulls (where they pecked at a fake red spot more than an actual beak) as an analogy. Perhaps we are like herring gulls irrationally enjoying or being attracted to something we cannot explain. Art is often abstract or exaggerates features and why we prefer one piece over another is not explicable. - When we see a lion behind the branches of a bush, our brains defeat the camouflage by connecting the dots. It must use probability chances are slim that such an outline would exist behind a bush that is not a lion. We also prefer slight concealment in art over full exposure. We prefer a semi nude to a full nude, for example. In a similar way, this could represent visual foreplay. - VR reminds us that, in the brain, no two patterns can overlap. We cannot multi task it is one process or the other even though there are 100 billion neurons. - VR, quite presciently, suggests that psychiatry will become a branch of neurology. The traditional psychiatric treatments the Freudian approach look into past life events as a means of explaining current psychiatric disorders. However, by looking at the brain as the source of mental

5 activity (and disorder), you can treat it like any other organ that is not working well. For example, you can give it drugs chemicals it needs but is not adequately producing. - Benjamin Libet s experiment is discussed the finger experiment involving free will. He told people to move their fingers at any time they chose. What he found was that the brain activity for the action happened a full three quarters of a second before the finger moved. Subjectively you feel you are moving your finger at that time, but objectively your brain started the movement earlier. This delay seems likely where the signal needs to travel from the brain to the finger. Perhaps natural selection eliminated the delay to avoid confusion (although the delay exists). Interestingly, natural selection does cause other delays to align senses. For example, our hearing is processed quicker than our vision (vision is a lot more complicated and takes longer to process). The brain delays the process of sound so that it can coincide with vision. - Schizophrenia is discussed. We all know that we have internal conversations with ourselves. Sometimes we extend our imagination to consider other people, even becoming them. But at all times we know this is our own internal voice and/or imaginationb. In schizophrenic patients, it seems they may not have this rational override. The internal voice is not considered their s. - It is argued that we blush to show we are honest.