Brain-Doidge

Until the late 1960’s the prevailing view amongst neuro scientists was that the brain is hard wired with specific parts being responsible for analysing input signals and/or sending commands to the muscles of the body.

In recent times experiments and observations around the world have shown that it is possible for the brain to adapt its operations so that functions, normally processed in one region of the brain can be performed by a completely different region. This phenomenon, known as neuroplasticity, is now widely accepted.

In “The Brain That Changes Itself”, Doidge outlines many of the remarkable experiments that have been conducted to establish the nature of brain plasticity and to indicate the extremely wide potential for overcoming disabilities that may inflict people from injuries, psychological traumas or even genetic make-up.

Doidge gives examples where it has been possible for the blind to see, the deaf to hear, stroke victims to recover motor skills, children with low mental abilities to become brilliant, 80 year old people to sharpen their wits, previously incurable obsessions and traumas to be cured. Doidge also indicates that neuroplasticity has implications for our understanding of love, sex, grief, relationships, learning, addictions, culture, technology and psychotherapy.

In the 1960’s Paul Bach-y-Rita (a neuroscientist born in NY city, who obtained medical qualifications and practiced in Mexico for some years then joined University of Wisconsin, Madison), developed an extraordinary device that was able to transmit visual signals to people who had been blind since birth. With a patient sitting in a barber’s chair, a digital camera was mounted above the patient’s head. The electrical signals from the camera were fed down to a plate pressed against the patient’s back. There were 400 small cells on the plate which vibrated when excited by the electrical signals. The cells vibrated strongly for a dark section of the screen to which the camera was pointed, while there was no vibration for bright sections of the screen. After a short time the brains of patients were able to interpret the signals and recognise basic patterns.

As well as demonstrating the flexibility of the brain, this work showed the incredible sensitivity of the skin to monitor and transmit closely spaced signals. Paul Bach-y-Rita went on to use these findings to make a variety of touch-based devices, including: a feeling glove for astronauts to improve their manipulation of tools during spacewalks, a glove for leprosy victims to have feelings in nerve-dead fingers, a glove for blind people to read computer screens, scalpels with sensing signals sent to a surgeon’s brain via a small plate held on the surgeon's tongue.

Paul Bach-y-Rita’s father, a respected professor, suffered a massive stroke. His brother, who knew nothing of the traditional methods for dealing with stroke, commenced a teaching program to bring their father back to walking and general competence, by a learning approach similar to that of a young child – including crawling around the backyard! This proved to be remarkably effective. The father had agreed to have his brain sectioned after death. When this was done it was found that a huge legion had put much of the brain out of action. Very clear evidence that the remaining healthy part of the brain had taken over functions not normally expected of it. In other words neuroplasticity was undeniable.

At the University of Wisconsin Paul Bach-y-Rita developed a large program of neuroplasticity research. As part of this work he made a major improvement in his early vision machine, reducing the electronic sensing to a small unit mounted on spectacles to generate electrical impulses sent to an array of 2000 electrodes in a plate placed on the patient's tongue.

Doidge quotes the case of a young woman, Barbara Arrowsmith Young, who as a young girl was exceedingly bright in some areas, but extremely retarded in others. She had poor spatial awareness and difficulty with symbols. As a teenager she had a nasty car accident which damaged her head and very nearly killed her. As she grew into her late teens and early twenties she studied other cases that seemed to have similarity to hers and she read of the work in Russia on a soldier who had lost half of his brain in a war incident. She was inspired by the work that was done in developing this man’s capabilities. To reshape her own brain she worked tirelessly at developing and practicing mental exercises, until she became competent in all the areas that had been lacking. In other words, purely by mental activity she had reshaped her brain – another very clear case of neuroplasticity.

Barbara recognized that the exercises she had developed for herself could be useful for many other people. With colleagues and friends she formed an organisation, known as the Arrowsmith School, to help people in need. This has been developed and improved and now offers exercises on the web at a site called ‘PositScience’.

Michael Merzenich is a researcher cited by Doidge as a major contributor to the understanding of neuroplasticity. He has done a lot of work using monkeys as his subjects. He has also developed many exercises to train specific areas of the brain. He believes that brain exercises can cure many diseases, such as schizophrenia. He showed that some people have learning difficulties because parts of their brain do not process visual or audio information as fast as the average person - this is particularly important for children and may explain reading and writing difficulties. He developed a programme of learning tools that he has called ‘Fast ForWord’. This is available on the web.

The book goes into some depth in explaining the modern tools, such as Transcranial Magnetic Stimulation (TMS) that can very precisely locate and even cause specific neurones to fire so that muscles operate. In early times this was done by inserted physical electronics, but now much can be done by devices and plates held close to the skull.

Using new sensitive techniques it has been shown that mental activity, such as practicing on a piano for several weeks will cause parts of the brain to actually grow in size. Rather intriguingly in one experiment with a fairly large number of subjects, it was found that this brain growth could be observed if people played an actual piano for an hour or so each day for a month, but surprisingly, growth was also observed in people who mentally practiced the piano (ie. they merely thought about their fingers operating on a virtual keyboard) for the same time period. Both groups showed real improvement in their playing ability; although, as might be expected, those who practiced mentally did not develop their skills as significantly as those who practiced physically.

In a similar fashion, actual and thought experiments were conducted on the development of muscle power. One group was asked to undertake 4 weeks of physical training while another group was asked to imagine physical training. The first group developed 30% stronger muscles while the second, thinking about training showed 22% stronger muscles; a surprising demonstration that thoughts can change the body. In other words a validation of the old saying “mind over matter”.

Brain scans showed physical changes in the brain do occur in experiments such as these. Thoughts actually change the structure of the brain.

It has now been demonstrated that psychotherapy (“treatment by talking”) cures by altering the strength of synaptic connections and structurally altering the interconnection between nerve cells. Freud had proposed this in 1895 with his concept of the integration of the brain and mind and his suggestions that ideas and feelings presented at the same time become fixed in the mind - for example, if a certain sound or smell was heard at the same time as some unpleasant event or trauma, then an unpleasant feeling (or fright) may be triggered whenever that sound or smell is experienced. This is confirmed by the more recent finding that ‘neurones that fire together, wire together’.

Freud’s methodology of letting the mind wander, which he called “Free Association”, is based on the idea that disparate events may have been linked in the past. By asking the patient to randomly wonder over their memories, some unexpected connections might be discovered and a cure to a phobia might be achieved by bringing this link out into the open and demonstrating that it is not relevant to the patient’s current life.

In two Appendices and a section ‘Notes and References’, Doidge reviews some very interesting ideas about human behaviour and interaction. He points out that while Homo sapiens originated some 100,000 years ago there was very little development of tools or culture – they lived very much the same as any other animal. Around about 50,000 years ago there seems to have been a significant awakening with the development of art, religion, and complex technology. There was little or no change in total brain size and physical structure, but apparently development in communication skills led to new neurone paths and relative growth in some parts of the brain to achieve more logical, rational thinking, plan

Recent studies of childhood brain development show that in the first two years of life there is significant formation of neural connections in the right hemisphere. This is related to non-verbal communication, such as recognition of faces, the interpretation of facial expressions and processing of music and speech tones. All this is very important for maintaining human connections and regulating emotions. Without a full, loving, exposure to other human beings in the first two years, society misfits are created.

Around 24 to 26 months of life the left hemisphere has a rapid growth spurt. This provides the linguistic and problem analysis basis for the adult human. It is also the area where explicit memories seem to be held; so it is only after the first 26 months that a child is able to recollect specific facts, events, and episodes. Prior to this, the unconscious, non-verbal, memories have been laid down.

In the adult life it appears that short-term memories are stored in the hippocampus and that sleep, particularly the rapid eye movement sleep (REM), is important in storing these memories for the longer term. It is a function of the hippocampus to make this transition from short-term to long-term memory. Doidge points out that the hippocampus will shrink with depression, high stress, trauma and/or older age, leading to memory loss (particularly short-term loss).

Experiments with mice have shown that a group exposed to interesting toys and playthings developed brains with more neurone connections and a larger hippocampus than an equivalent group confined in blank boxes. A similar phenomenon is shown in humans where a challenging life is well known to develop the brain and make an intelligent person.

Socrates in ‘The Republic’ argued that a person could train his mind in the way gymnasts train their muscles. And it is now recognized that to keep the brain fit we must learn new things rather than replaying already mastered skills. Of course physical exercise is also important, since it strengthens the heart and improves the blood supply to the brain.

With proper attention to keeping the brain alive and alert many people have shown how their can be very skilled and innovative in older age. Amongst other examples, Doidge remarks that Frank Lloyd Wright designed the Guggenheim Museum at age 90.

This is an excellent book with clear explanations and relevant examples. It shows how the brain has played its critical role in Homo sapiens evolution, how it maintains human beliefs, interactions and current human life. It also implicitly indicates how humans might evolve in the future.