PROF. DR. DICK SWaaB WE ARE OUR BRAIN Brains, consciousness and faith: neurobiological aspects Everything we think and do is determined and carried out by our brain. The unheard evolutionary success of mankind and the many restrictions of the in- dividual human being are determined by this organ. The build of this incredible machine determines our possibilities, our restrictions and our character; we are our brain. The rest of our body is merely here to feed our brain, to move and to make new brains by reproduction. Brain research isn’t just a search for handicaps, but is evolving more and more into a search with the central question why we are the way we are, a quest to find ourselves. 2 ACADEMY MAGAZINE HERFST 2005 HERFST 2005 ACADEMY MAGAZINE 3 The building stones of our brain are nerve cells or neurons. depressants are so successful that there is a lot of abuse. With They specialise in (i) the gathering of information from other cancer, terminal pain can be treated by stimulating a brain elec- nerve cells and hormones from the rest of our body and, throu- trode, which is implanted in the central grey area of the brain, gh our sense organs, from our environment; (ii) the integra- by your self. This way opium-like substances are set free in the tion and processing of this information, taking decisions about brain and the pain will become bearable. Stimulation using such these matters and (iii) the execution of decisions in the form of deep electrodes is now also used to treat the shaking which oc- movement, hormones, regulating the body processes, and the curs when you have Parkinson disease, clustered headaches production of an endless stream of thoughts. I am not impres- and to treat compulsive actions. A gene is discovered which, sed by the evidential value that comes with the anecdotes of in a certain family, is responsible for excessive aggression. heart transplant patients who experience a change of character Somewhere on the x-chromosome there is a gene that could in which the distinct characteristics of the donor come forth increase the chance of becoming homosexual. There are brain (Pearsal et al., J. of Near-Death studies 20, 191, 2002). If we want scans that make activated areas in the brain light up that we to take these cases seriously we have to have a good controlled use to read, do maths, listen to music, hallucinate, to be in love study. There must be a certainty that the recipient doesn’t get or to display sexual behavior. Damage in the front area of the any information about the donor. There can’t be unwanted ma- cerebral cortex (= prefrontal cortex) can lead to dysfunctional nipulations of the interviews and the effect of medicines which social and ethical behavior (Anderson et al., 1999). Pieces of are taken after the transplant must be taken into account. brain tissue from a fetus are transplanted to treat Parkinson’s di- sease. New discoveries are made in rapid succession because of The computer metaphore the recent huge technical progression made in neurosciences. If we consider the brain to be an information processing ma- chine, the computer metaphor isn’t that bad. Also, when we We transform our own brain into an unique machine look how the building stones of our brain work, this metap- The computer metaphor is only partly applicable. The ‘hard- hor comes to mind. The brain weighs 1,500 grams and con- ware’ of our brain isn’t just soft, but some systems are also very sists of 100 billion (10x1010) neurons (about 20 times more plastic. Our brain is a living machine, which changes constantly than there are people in the world), twice as much glia cells by using it, especially during the development. Everything we (the glia is a support tissue in the central nervous system) and do and observe during the development of our brain can result at least 1000 times as much places here nerve cells make con- in a permanent change concerning the number of cells, circuits tact or, as Cajal put it, holding each others hand, the synapses. and cell contacts. Our environment and the use of our brain The nerve cells are bound by over 100.000 km of nerve fiber. strongly and permanently influence the build and so the func- These dazzling amounts of cells and contacts work so ef- tion of the brain. That is why our brain becomes permanently ficiently that our brain has the energy consumption of just a uneven in build and function; the brains of identical twins are 15 Watts light bulb. This means that the entire energy costs unique because of this. Genetics are just a small factor when of one person during his entire life, considering the current it comes to the development of the brain. The brain develop- prices, are less than 1000 euro, as Michel Hofman calcula- ment of a child is influenced in the uterus by hormones and ted. You can’t get a decent computer for that kind of money. the amount of stress that the mother experiences. The deve- An incredible machine with parallel switches, better equip- lopment is endangered by medicines, alcohol and nicotine ped for image processing and associating than any computer. used by the mother during pregnancy. If the mother smokes, The nucleus suprachiasmaticus, the clock of our brain, is the offspring is more likely to become aggressive and criminal. just ½ mm3 in size. This is enough to control all of our day The brain produces massive amounts of cells and connections. and night rhythm (wake/sleep, eat, drink, reproducing, The way the brain systems function determines which cells and hormone mirrors, etc.). With 1500 cm3 of brain (3 mil- connections will remain to exist. The brain cells struggle for life lion times as many) we can do a lot. The product of the is called ‘neuronal Darwinism’. Not only the way a child is prac- functioning and interaction of all those billions of nerve cells is tising his movements decides the build of the brain, and the our ‘mind’. In this materialistic view, the spirit isn’t replaced by later functioning, but the build and functioning of our brain is matter but the spirit is the product of matter, of our brain cells. also permanently organised by everything the child experiences, sees and thinks. Multiple factors influence the brain in the early Disorders in the build up of this efficient information proces- development stages. They decide, later in life, how we experien- sing machine during the development or later in life result in ce ourselves: a man or a woman (gender) and if our gender mat- psychiatric or neurological illness or sickness in the hormone ches with our sexual organs. With transsexuals we found female production by nerve cells. Not long ago psychiatrists healed brain structure in male brains and vice versa. The characteris- about fifty percent of their patients with psychoanalytic therapy, tics of this structure match the feeling to be a woman or a man, the rest of the patients on the waiting list healed themselves. not the genetic gender or the gender of the sexual organs. Our Now these disease patterns can be treated in a better way by sexual orientation is also determined in the uterus by an in- influencing the chemical messengers with psycho pharmaceu- teraction between sexual hormones and developing brain cells. tics. With the help of a microscope you can see that the normal The foundation of this behaviour is concealed in the non- brain development of a patient suffering from schizophrenia is plastic structures of our brain, which explains why no doc- disrupted halfway during pregnancy; because of this schizo- tor has ever ‘healed’ a transsexual believing he or she is of phrenia became a brain disorder, which is now easier to treat the opposite sex, or to change a homosexual into a hete- with medicine. To quote the awarded poet Kees Winkler: ‘If I rosexual. During the first years of our life our environment don’t take my pills, I become more schizo than phrenic’. Anti- also determines the build of brain systems related to lan- 4 ACADEMY MAGAZINE HERFST 2005 guage. That’s why we have one permanent native language. (alien hand syndrome). Patients with cut connections between In some brain areas, the development of new contacts bet- the left and right half of the brain or with a damaged medial ween nerve cells goes on until after our 65th birthday. frontal cortex sometimes are not able to recognise their limbs Because no one’s experiences and thoughts are the same, as their ‘own’. These limbs can act independently from the ow- every brain becomes unique during the development pro- ner. The two hands operate in completely opposite ways (one cess. This is how character and personality come into being. dresses, the other one undresses). A patient’s hand grabbed Our brain creates our culture and our culture shapes the her own throat and tried to strangle her. Alien hand syndrome development of our brain. We make our own brain uni- could occur also with patients who suffer from corticobasal de- que – into a person, and sometimes even into a personality. generation, an illness which makes parts of the brain degene- rate (Biran and Chatterjee, 2004). Free will? Our brain is unique and that’s why we are able to produce a The law suggests that a healthy brain is needed to have free will. unique poem or painting, or to create unique experiments. Are you someone with a healthy brain? Is that even possible Eccles believes that the evidence of free will is the creativity after everything we have been through after our conception? of the scientist.