The Brain: The Story of You - Neuroscience Book About Human Consciousness & Mind | Perfect for Psychology Students, Book Clubs & Self-Discovery

David Eagleman is a celebrated TV presenter and neuroscience professor at Baylor University in Texas who has conducted ground-breaking research, especially in aiding chronic drug-users combat addiction by providing them with real time imaging of their craving and suppression networks, and also in the field of so-called ‘sensory substitution’ by enabling the deaf to hear through development of the ‘Variable Extra Sensory Transducer’ (VEST), a clothing-like device worn around the torso and equipped with tiny detectors to convert sounds into dynamic patterns of vibratory signals. This book is a close, at times almost word for word, transcription of his recent televised series with the same title, i.e. The Brain, and, like the TV version, is a lively, invigorating and highly informative introduction to the subject. Given his hands-on expertise, Eagleman is unsurprisingly at his most eloquent and authoritative when discussing various parts of the brain and their respective functions. Here we learn about vitally important constituents like the parietal cortex (a wide range of functions including reasoning and processing sensory data), the prefrontal cortices (handle learning, abstract thinking, planning and self-control - especially the medial, dorsolateral and ventrolateral areas which regulate self-consciousness, willpower and emotional impulses, take longest to mature and therefore hugely influence the behaviour of young people), the orbitofrontal cortex (recognizes bodily states like hunger, thirst and anxiety), anterior cingulated cortex (monitors performance), hippocampus (enables memorization, especially spatial), cerebellum (responsible for alertness, balance and motor skills), thalamus (refashions sensory processing and regulates consciousness and sleep), hypothalamus (controls energy use and the metabolism), amygdale (reacts to danger, processes pain, fear and aggression), the motor cortex (controls muscles), visual cortex (enables sight), the dopamine-loaded nucleus accumbens (arouses expectations, encourages self-gratification and addiction), the corpus callosum (links the two brain hemispheres) and last but not least, the glial cells (do regular house-keeping operations like brain waste disposal). The reader is introduced to terms like ‘plasticity’ (the brain’s ability to rewire and physically reorganize itself, especially after injury),‘procedural memories’ (repeatedly absorbed information which has become hard-wired into our cerebral circuitry), ‘neural correlation’ (the mapping of firing neurons to our outward behaviour),‘neural reusability’ (requisitioning neurons to help out in multiple brain scenarios), ‘proprioception’ (sensory awareness of our own bodily motion), the ‘binding problem’(how our various sensory inputs – visual, auditory, olfactory, tactile and gustatory - get combined into a unified, meaningful impression of external reality), and how ‘sensory transduction’ helps with the binding problem by converting photons (for color recognition), air compression waves (for hearing), scent molecules (for smell) etc. into formats accessible to sensory interpretation. Finally, there are fascinating references to major recent progress in neurological research, in particular techniques like electrode implantation (to transmit mental instructions via computer implants to robotic limbs), sensory substitution (e.g. the VEST already mentioned) to enhance non-existent or defective faculties, TMS (i.e. transcranial magnetic stimulation - which uses magnetic pulses to induce activity in particular places and/or reboot the brain), advanced EEG (i.e. electrocephalography – which measures neural activity using electrodes attached to the scalp to record brain wave frequencies, e.g. alpha (when the brain is at rest), beta (during problem solving), delta (when asleep) and theta (during deep relaxation)), fMRI (i.e. functional magnetic resonance imaging – which creates ultra high-resolution images of cerebral processing from observations of blood flow in the brain), and finally something called ‘serial block-face scanning electron microscopy’ - which assembles scanned images of micro thin slices of the brain (currently only of rats) into a ‘connectome’, i.e. a three-dimensional model of all constituent neuronal connections.Despite all this very impressive progress which Eagleman dutifully records, it has to be pointed out that neuroscience has so far achieved only a very limited understanding of how the brain actually works. Neural correlation especially has enabled a very thorough identification of areas responsible for a wide range of human behaviour, psychological as well as bodily. But whereas we now know much of what the brain does and where within itself it does what it does, neuroscience has yet to account for how it does what it does, an explanation for consciousness, the ‘hard problem’ par excellence, remaining particularly elusive. Why? Because the holy grail of neurological research – getting to grips with the brain’s internal software, no less – has yet to be realized. In these circumstances, it’s perhaps little exaggeration to say that its practitioners can be likened in some ways to a band of stone age people who, suddenly finding an abandoned car in the desert with the key still in the ignition, start playing with the dashboard controls, pressing switches, turning knobs and pulling levers, carefully noting as they do so that various lights come on and certain engine noises can be heard, some of which dim or stop when, after popping the hood, they yank out the odd cable, unscrew a few caps or drain a fluid reservoir. Do they have a clue about internal combustion, let alone electricity? No way.Eagleman’s infectious optimism and enthusiasm do much to make up for the reservations I’ve just expressed. They also let him get away with a certain amount of bold exaggeration. Early on in the book for instance, he tells us that instead of experiencing the outside world directly ourselves, we only experience a fabricated model of reality, one seamlessly and instantly assembled by the brain for our sensory benefit. The real world, he says, is ‘colorless, odorless, tasteless and silent’ and the brain must work overtime to compensate for this barren environment by interpreting the various photons, air compression waves, molecular concentrations, pressure, texture and temperature signals it receives into a meaningful representation of external reality. So far, so good, but Eagleman gives insufficient credit to the brain for the superb job it does. All the incoming signals just mentioned are also an integral part of reality and, far from being somewhat of an illusion or a mere ‘show’, the impression of reality the brain puts together is a remarkably, accurate, dependable and consistent one – indeed, it cannot be otherwise because were this the case we would have utterly failed to successfully manage our environment and evolve as a species. It’s certainly no accident that six expert water colorists, for instance, painting exactly the same scene simultaneously from the same position, will record almost exactly the same visual impression – so much for the notion they individually make much of it up in their heads!Eagleman does make a valiant attempt to tackle the problem of consciousness, but has to fall back ultimately on the old philosophy of mind concept that it’s a mental process which automatically emerges (‘emergentism’) once a sufficient threshold of cerebral complexity is attained. In support of this view, he cites the analogy of a) an engine’s mechanical parts which individually achieve nothing but collectively enable the motor to function and b) that of ants programmed to work seamlessly together for a common purpose, but (a) fails because the mechanical example is non-biological, and b) too because each ant has its own nervous system conferring a limited capability for independent activity. He also cannot seem to make up his mind where consciousness fits within the overall functional hierarchy of the brain, calling it sometimes a ‘passenger’ or ‘stowaway’ and at other times the ‘CEO’ or the ‘driver’. Perhaps it’s best to ask ourselves what the lowest manifestation of consciousness in the natural world actually is. Does an earthworm, for instance, exhibit ‘consciousness’ when it reacts instantly to human touch? Or is such instinctive behaviour to be dismissed merely as that of a primitive nervous system? If so, what is the dividing line between a nervous system and consciousness? Could consciousness be viewed as just a super-highly developed and sophisticated type of nervous system? Eagleman also seems to posit a rigid separation between consciousness and unconsciousness. But is this reasonable? Many of us are sometimes vaguely aware - even when technically asleep - that we are unconscious; we may even remind ourselves during a dream (especially an hour or two before waking up) that it simply is nothing but a dream, enjoy the show and go willingly along for the ride. Maybe consciousness and unconsciousness should be viewed therefore as denoting not two separate but one single process, e.g. like a ‘fade to black’ dimmer light which can go from brightness (full consciousness) to pitch darkness (near total unconsciousness) and vice-versa. In this connection, it should be recognized that one can when fully awake be simultaneously conscious and unconscious – as when one is conscious of talking to someone but unconscious at the same time of another individual, activity or thing close nearby. The verbal ambiguity attaching to the word ‘unconscious’ which this example demonstrates is why the reluctance of contemporary philosophers and neurologists (including Eagleman) to employ the unequivocal Freudian term ‘subconscious’- to denote purely our mental activity which takes place either when one is asleep or which one is not consciously aware of when awake - is to be deeply regretted.A most interesting point in the book is that whereas newly born animals come invariably hard-wired with an extensive range of survival skills to cope with their new environment, the human baby is virtually unequipped at birth to do so. Instead, it must learn these skills as quickly as possible through trial and error. Two million new synapses, i.e. neuronal connections, are therefore formed every second in the infant brain, resulting in a hundred trillion by age 2 - twice that of an adult; hence parental nurturing and interaction with the outside world are vitally important for its early development. Neural pathways consisting of countless new strings of neurons are constantly built to reference and represent this newly acquired knowledge as we develop, a process which slows down dramatically after we reach maturity and which is accompanied by a progressive withering away and discarding of pathways which have lapsed into disuse. This is all great stuff, but once again Eagleman goes overboard by inferring that just because young people necessarily undergo a deep and sustained process of social interaction to learn about the world and grow up, all the rest of us should do the same in order to maintain our mental fitness and lead fulfilling lives – 'who you are is where you’ve been’ is how he sums it up. Yes, it’s obviously important to exercise our minds and bodies as much as possible and not to switch off and shut down as we age, but do we need the constant interactive proximity of others to succeed in doing so? Possibly he is unaware of the long and noble tradition of asceticism in both western and eastern culture, especially as practised by the Cynic philosophers of ancient Greece, by members of isolated, desert-based communities like the Essenes in Palestine, and by hermetic early Christian (especially Irish) and Tibetan Buddhist monks. All these adherents believed extreme self-denial and physical isolation from others to be the best route to heightened consciousness, inner peace, emotional satisfaction and contentment.Eagleman concludes his account with a brief survey of how neuroscience might benefit from anticipated progress in artificial intelligence and automation. Here, he cannot be blamed for an over-optimistic outlook (haven’t advances in these fields already done wonders for our understanding of how the brain works and enabled its capabilities to be enhanced and extended in hitherto undreamt of ways?). Yet a sober appreciation of the sinister downside of runaway AI and robotics would not have come amiss: as Asimov, Kurzweil, Hawking and others have repeatedly emphasized, therein lies the road to our future obsolescence and possible ultimate extinction as a species.