This paper's aim is to present some of the new, impressive discoveries of the neurosciences concerning the human brain and to discuss the impact they have on education and especially on preschool education. These discoveries are so profound that the decade 1990-2000 has been named 'Decade of the Brain'.
Recent scientific developments such as Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) have rapidly advanced our knowledge of the brain and how it works, moving us out of the age of speculation into a new era of brain mapping and understanding. New theories of consciousness, learning, and intelligence are emerging to help guide the next round of discoveries. For example, the Nobelist Gerald Edelman (1992) proposes that natural selection over the millennia has resulted in a modular brain with tens of millions of basic neural networks hard-wired at birth. Each of these networks is adapted to a very specific purpose, either monitoring and regulating the internal worlds of the body or intercepting and interpreting the messages from the environment. Included are emotional, memory, and reasoning systems which allow an individual to adapt to changing conditions during his or her lifetime.
All these new insights into brain development are more than just interesting scientific data. They infuse new passion into the political debate over education and especially over preschool education and day care. There is an urgent need, say child development experts, for preschool programs designed to boost the brainpower of youngsters.
But let us first take a brief look at the brain. The human brain is probably the most complex organized matter in the universe. There is an enormous number of brain cells (neurons) - 100 billion - with potential for an infinite number of connections (synapses), "all waiting to be woven into the intricate tapestry of the mind. Some of the neurons have already been hard-wiredbut trillions upon trillions more are pure and of almost infinite potential" (Begley, 1996).
Concerning its nature, the fabric of the brain is set down as a result of the interaction of genetic blueprints and environmental influences. Normal growth of the brain is the background for an adequate mental, linguistic and intellectual development, and the subsequent competence and performance of the individual. This is analyzed in the formation of adequate and appropriate 'neural circuits' in the brain.
The brain differs from most other body organs in that it has its growth spurt during the prenatal period and the first few years after birth. The brain has reached half its final mature weight as early as six months after birth and 90% of its final weight by the age of eight. The body as a whole only reaches half its mature weight by age ten. The implication is that the brain is most vulnerable in some respects to damage during this rapid growth spurt.
Neuroscientists, studying the brain in greater detail than ever before, find that if there is a lack of development that should take place in the earliest years, the deficits can never fully be made up. In some cases, the damage is irreversible. There is now abundant anatomical and behavioural evidence that, if neural circuits of the brain are not brought into play during the early years and more specifically at certain critical times of development, the so called 'windows of opportunity', they may never be capable of functioning or at least function to their full potential. Chimpanzees reared in darkness may be forever blind. According to Rita Rudel (1978) early deprivation may have similar effects as brain injury, while well-timed early encounters with the task requirements may prevent the appearance of a deficit in spite of an early lesion.
These effects of damage are likely to differ according to when they occur. For instance, prenatal or very early in life damage to the brain tends to be less likely to result in specific deficits, but more likely to lead to a general lowering of intellectual abilities. This is due to another feature of the brain called 'plasticity'.
More specifically, the brain is characterized by locality as well as flexibility of function. While many functions are related to specific areas of the brain, many functions can in fact be re-learned by related brain tissue either in the same hemisphere or in the opposite hemisphere. It has been found that if massive injury occurs to one hemisphere early in infancy, the other one can acquire, with proper stimulation, the functions of the injured hemisphere, although with some deficit remaining.
In other words, genetic contribution provides a framework which, if not used, will disappear, but which is capable of further development given the optimal environmental stimulation and education at the appropriate time. The environment after birth helps forge the neural connections that underlie later learning. Like a sculptor, the child's experience prunes away unneeded - or unused - synapses, while strengthening those patterns of connections - the 'neural circuits' - that are repeatedly used. In this way, habits of the mind may become, quite literally, structures of the brain. In conclusion, we may say that the experiences and the early childhood education determine whether a child "grows up to be intelligent or dull, fearful or self-assured, articulate or tongue-tied" (Begley, 1996).
What happens, or does not happen, during the first six years of life decides in large part the child's destiny for the rest of life. Although many children can benefit from later intervention, the costs of reversing the effects of a poor start increase as the child grows older, and the chances of success diminish. The developing brain is so malleable it can incorporate behavioural problems into its circuits as readily as it might pick up love.
The quality of parent and family interaction is a major influence on the difference between good and poor outcomes for the child. Infants thrive on one-to-one interaction with parents. Songs and happy talk evoke trust and a sense of security which builds confidence for exploration. This sense of security is the basis for forming good relationships with other children and adults. Infants' early experiences provide the building blocks for intellectual competence, language comprehension, good emotional balance and social skills. Feeling liked and loveable is the beginning of liking and being able to love, and the foundation of self-esteem. Touching, holding, talking and reading to the infant seem to be the most effective spurs to later development.
Such stimulation makes it possible to learn how to learn, to make choices, see relationships, and develop higher level thinking skills. It creates a demand for language, the raw material of thought. Words are tools used to express needs, wishes, and later, hopes and ideas. Without good command of language, the child will be shut out from much that could make life interesting and worthwhile.
The developing brain is so robust it can sometimes overcome even severe physical trauma, yet so fragile that a mother's prolonged depression can imprint her infant's brain for a lifetime with the neurochemistry of sadness. In other words, a mother's prolonged depression can change her infant's brain, significantly reducing activity in the parts regulating joy, happiness and curiosity. The intimate connection between mother and child is more than enough to condition the latter's neural circuits. Neuroscientists and psychologists have shown that an infant raised in an atmosphere of fear or neglect is subjected to biochemical overdoses of stress hormones that alter the young brain's circuitry.
Their findings reveal the nature of learning - how neurons physically blossom in response to stimulation like a flower responding to sunlight - and the importance of critical periods or 'windows of opportunity' for brain development. These 'windows of opportunity' are periods during which the brain is biologically programmed and demands certain types of input in order to create or stabilize certain long-lasting brain structures that underlay a certain ability. For example, children who are born with a cataract will become permanently blind in that eye, if the clouded lens is not promptly removed. This happens because the brain's visual centres require sensory stimulus during the 'window of opportunity' for vision in order to maintain their still tentative connections.
It is during these periods that the environment can influence how an individual's brain is 'wired' not only for functions such as vision but also for maths, language, music and physical activity. If these 'windows of opportunity' are missed - if the brain does not receive the appropriate stimulation - it is very difficult, though often not impossible, for the brain to re-wire itself at a later time. The fact that partial impairment of language development is sometimes associated with transient hearing loss due to infection in early childhood is another striking example of the need for relevant experiences during these critical periods. The 'windows of opportunity' of the earliest years according to Begley (1996) are found on the following table.
|Windows of Opportunity for||Age|
Children acquire a significant amount of knowledge even before preschool. The most critical learning period is the period before a child enters kindergarten. By the age of three, a child will absorb and recognize about 1000 words, which is two-thirds of the adult everyday speaking vocabulary. A child has internalized a complex language system and over a 5000 word vocabulary by the age of four.
Quality early childhood programs provide the foundation for success, often preventing future problems. Early learning opportunities can help the brain grow in ways that make it smarter and more effective for the rest of one's life. The younger the child, the more effective mental stimulation is on the physical structure of the brain and on intelligence. By the time a youngster reaches first grade and thereafter, the impact of learning on the brain is not quite as powerful.
The brain's greatest growth spurt, say neuroscientists, draws to a close around the age of ten, when the balance between synapse creation and atrophy abruptly shifts. Over the next several years, the brain will ruthlessly destroy its weakest synapses, preserving only those that have been magically transformed by experience. The experiences that drive neural activity are like a sculptor's chisel conjuring up form from a lump of stone. In other words, potential for greatness may be encoded in the genes, but whether that potential is realized as a gift for mathematics or music, depends on patterns etched by experience in those critical early years.
Psychiatrists and educators have long recognized the value of early experience. But their observations have until recently been largely anecdotal. In our days it is neuroscience that is providing the hard, quantifiable evidence that was missing earlier.
The lesson that can be drawn from the new findings is that we must take into consideration all these findings and pay special attention to quality preschool education. Good, affordable day care and preschool education is not a luxury for working parents but essential brain food for the next generation. For, while new synapses continue to form throughout life, never again will the brain be able to master new skills so readily or rebound from setbacks so easily. If parents and policymakers don't pay attention to the conditions under which this delicate process takes place, we will suffer the consequences.
The brain is so hungry for stimulation that, with proper attention early enough in life, a disadvantaged child's IQ can be raised up to 30 points, the risk of some forms of mental retardation can be cut in half, and common learning disabilities such as dyslexia can be corrected. Conversely, denied proper stimulation, the brain atrophies, its neural connections withering like dying leaves.
The nervous system and the brain are the physical foundation of the learning process. Neurosciences - which study the human nervous system, the brain and the biological basis of consciousness, perception, memory and learning - seek to link our observations about cognitive behaviour with the actual physical processes that support that behaviour.
Some of the key findings about the human brain, which are finding application in such diverse fields as biofeedback training, psychoneuroimmunology, business and education, can be summarized as follows:
The brain has a 'triune' structure. Our brain is really three brains - the lower or 'reptilian' brain that controls basic sensory motor functions such as breathing and heart beat; the 'mammalian' or 'limbic' brain that controls emotions, memory and biorhythms; and the 'neocortex' or 'thinking' brain that controls cognition, reasoning, language and higher intelligence.
The brain is not a computer. The structure of neuron connections in the brain is loose, flexible, 'webbed', overlapping and redundant. It is impossible for such a system to function like a linear, or even parallel-processing computer. The brain is better described as a 'self-organizing system' than a computer.
The brain changes with use, throughout our lifetime. Mental concentration and effort changes the physical structure of the brain. As the brain is used, certain patterns of connection are strengthened.
This is an oversimplified view of the brain since each of the three building blocks provides many additional functions. All three parts work through an electrochemical process which distributes both chemicals and electrical charges through an incredible network of tubes extending throughout the brain and body.
Learning is a natural, biologically generated function promoting survival, growth, and development. More specifically, learning consists of the growth of additional neural connections stimulated by the passage of electrical current along neurons and enhanced chemicals (neurotransmitters) discharged into the gaps between synapses. As a particular pathway is used, additional connections ease future use of the same neurons. This is analogous to water cutting channels that eventually grow into streams and rivers. The more extensive the web of these connections, the greater the brain's capacity in the future to take in information and skills, as well as to integrate them and apply them appropriately to life's daily challenges (Diamond, 1987).
Another fact concerning learning is that in order for the brain to construct knowledge, it must take in something that it can manipulate. The only way the brain takes in data for construction is through the sensory perceptions that enter through the windows of its five senses. Show-and-tell teaching methods (lectures, demonstrations) diminish the number of possible avenues to the brain that can be activated. On the contrary, enriched environments in which a learner makes inquiries or uses educational material increases the likelihood that something will be constructed. And as the brain constructs connections among neurons, the organization of events, objects, and relationships are connected in successively interwoven layers of categories. The result is that human knowledge is stored in clusters and organized within the brain into systems that people use to interpret familiar situations and reason about new ones.
In other words, the brain functions as a pattern maker, pattern follower, and pattern sensor. From early childhood, the brain establishes patterns based on both verbal and nonverbal messages that come to us from parents and other authority figures. These patterns delineate who we think and feel we are and what levels of success and fulfilment we can expect from our life experiences. These patterns then tend to be acted out in daily experience, generally without our recognizing the connection between them and our actual behaviour and experience (Caine and Caine, 1991).
In order to bring meaning to life experiences, the brain looks for patterns in daily experience that agree with its own internal patterns. New learning is facilitated when the brain can relate newly introduced material to something it already knows (Caine and Caine, 1991; Herbert, 1985). Working directly and consciously with the brain's pattern making function is an example of accessing 'expanded brain function' and is at the core of programs for expanded human learning and behaviour change, whether these programs are oriented to academic growth, athletic accomplishment, health, emotional or spiritual growth (Tart, 1987).
More specifically, psychologist Charles Tart of the University of California at Davis suggests that we have a great range and variety of states of awareness, which could serve us richly, if we could access them at will. If we were to explain this phenomenon physiologically, we would describe the human brain as operating in a normal range of frequencies from 1 to 30 cycles per second (cps), and we would note that at different frequencies humans can access different capacities, abilities, and talents (Caine and Caine, 1991; Diamond, 1987; Gazzaniga, 1985; and Ornstein and Sobel, 1987).
We will look at four of them. When we are fully focused (for example, listening to a teacher's presentation), we are tuned to our fastest frequency channel, the first channel.
Channel 1 is from 30 to 16 cps. When tuned to this mode, we focus outwardly into the world in order to cope with a problematic situation. New learning in this frequency is limited to 'grazing' for bits of information, which go into short-term memory and are quickly forgotten.
Channel 2 is the relaxation channel from 15 to 12 cps. This is a special Stress Release gate. As a person relaxes via calming imagery, the brain wave pattern would change to include more waves in the Channel 3 range.
Channel 3 which functions at 11 to 7 cps, appears to be our learning channel and is routinely accessed by preschoolers and in brain-friendly school settings, making learning more efficient, easier, and often effortless. When we are tuned into Channel 3, learning can occur with up to 300% greater efficiency than in Channel 1 (Lozanov, 1978; Schuster and Gritton, 1986).
Channel 4 (7 to 4 cps) is our highest resource state. From that channel, we access our intuitive thoughts, inspirations, insights, and inventive talents. Here also are the wellsprings of our artistic talents and faculties. In order to access this high-resource state, an ability to expand our usual awareness to include an inner focus and reverie state in which we are both very relaxed and hyperalert is required. Many of us reach this state, without recognizing it, when we are in deep thought in a quiet environment or perhaps in the state that yoga nidra leads us.
Wolfgang Amadeus Mozart wrote of his ability to enter a reverie, or dreamlike state and while there to conceive his musical compositions complete, including orchestration. He then brought himself out of his reverie and notated his works. Einstein also entered a reverie state for much of his insight work. We also see evidence of it in biographies of Edison, Curie, and others (Hadamart, 1945).
|Brain Frequency Ranges|
|4 to 7 cps||8 to 12 cps||12 to 14 cps||16 to 30 cps|
|High Creativity /Pattern-maker Channel||Learning Channel||Relaxation Channel||Action Channel|
|Brings Highest Reources||Processes New Learning||Carries Out Learning|
|Home of Super Abilities||Home of Real Learner||Home of Transition||Home of Appropropiate Action|
|Reverie state||Calm state||Sees ways to take action||Stressed state|
|Inner senses||Inner senses||Outer five senses|
|Available with practice||Relaxed mode||Reason critical thinking|
|Mozart, Currie||Effortless learning||Acknowledges only external reality|
|Sleeping on a problem||Stress release||Stress release||Critical analysis of data|
|Creative flashes||Inner prime time||Sit up straight and pay attention|
|Spiritual inspiration||Joy of learning|
|Flow state activies|
Until very recently, ignoring the existence of these channels, we have not considered this ability to be part of what we could learn in schools. We now know that this ability can be readily facilitated by most classroom teachers and can help young learners explore the farther reaches of their learning and performance potential - an exciting and beneficial lifelong skill. We could also reach this channel through yoga.
Being tuned to channel 4, we could send the message we wish to realize to our brain. If this message is clear, our brain gets busy helping us achieve it. It creates a new enabling pattern, which then operates below awareness to drive behaviour toward better outcomes.
Calling on our expanded powers to bring about long-term change is not unfamiliar in our society. Athletes worldwide use a pattern-creating method to improve their performances. We simply did not know until recently the brain mechanisms underlying this phenomenon. This approach is used nowadays in psychoneuroimmunology, as well as in biofeedback training, in which subjects can learn to control headaches, blood pressure and other biological functions.
It is exciting to recognize that every person has a huge untapped potential or, as Lozanov calls it, a 'reserve', which, when tapped, brings us in touch with outstanding creative abilities not usually within the realm of our voluntary control.
Another issue related to learning which has been approached from another point of view, is intelligence. Among the notable theorists in this area, David Perkins (1995) has advanced a particularly powerful idea. He proposes that there are three different kinds of intelligence: neural, experiential, and reflective. Neural intelligence is that with which we are born. The networks established at birth vary somewhat from person to person, allowing some individuals to process incoming signals at a faster rate or with more discrimination than others.
The second and third intelligences - experiential and reflective - are open to change. As we learn a new subject or activity, Perkins postulates that experience causes new neural connections to develop. As we reflect on how we behaved in past situations and see alternative routes, new connections are made.
Howard Gardner is another eminent theorist in the area, whose work has deeply influenced the scientific community. Gardner's (1983) theory of multiple intelligences takes a somewhat different track but it is not inconsistent with the work of Perkins. The current seven intelligences postulated by Gardner (spatial, musical, linguistic, logical-mathematical, kinaesthetic, interpersonal and intrapersonal) exist at different levels in the neural networks of individuals at birth but could be enhanced, he believes, through experience and reflection.
The work of Hart, Caine and Caine (1991), Zafrana (1979; 1992) and others, which examine such human brain propensities as information seeking, processing, and organization, attempt to capitalize on these propensities by organizing instruction to be more brain-compatible. Also since the role of emotion is now known to be of great importance in learning, strategies for its inclusion in instruction are now a component of these theories.