Do Infants Only Learn "One" Language Well? (2)

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Do Infants Only Learn "One" Language Well? (2)
Do Bilingual Children Develop Their “Intelligence” Less?

The myths arise from a combination of factors. Since language is important culturally and politically, these considerations colour numerous arguments, including brain research findings, to favour one “Official” language to the detriment of others.




Certain medical observations have played their part: cases of bi- or multilingual patients completely forgetting one language and not at all another after a head trauma helped foster the idea that languages occupied separate areas in the brain.



Studies conducted at the beginning of the 20th century, which found that bilingual individuals had inferior “intelligence”, were carried out with faulty methodologies, being based mainly on migrant children who were often undernourished and in difficult cultural and social conditions.

The protocols should have taken into account that many of these children had started learning the language of their host country around the age of 5, 6, or later, and, without a strong command of that language, they had problems learning other subjects. In short, we cannot meaningfully compare the intelligence of monolingual children from native, often well-off families with that of multilingual children from primarily underprivileged environments with limited family knowledge of the dominant language.

"Understanding the Brain", The Birth of a Learning Science, 2007, page 118

Do Infants Only Learn "One" Language Well? (1)

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Do Infants Only Learn "One" Language Well? (1)

Can A Young Child’s Brain Only Manage to Learn One Language at a Time?

Today, half the world population speaks at least two languages and multilingualism is generally considered an asset. Yet for long, many have believed that learning a new language is problematic for the native language.

Superstitions on this die hard and are often based on the false representation of language in the brain. One myth is that the more one learns a new language, the more one necessarily loses the other.

Another myth imagines two languages as occupying separate areas in the brain without contact points such that knowledge acquired in one language cannot be transferred to the other.




From these ideas, it has been supposed that the simultaneous learning of two languages during infancy would create a mixture of the two languages in the brain and slow down the development of the child. The false inference is that the native language had to be learned “correctly” before beginning another one.

"Understanding the Brain", The Birth of a Learning Science, 2007, page 118

Have We Two Brains? (5)

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“Is There One ‘Left-Brain’ & Another ‘Right-Brain’?” (5)
No, None Escientific Evidence Confirms That

No Scientific Evidence, indeed, indicates a correlation between the degree of creativity and the activity of the Right hemisphere. A recent analysis of 65 studies on Brain Imaging and the processing of emotions concludes that such processing cannot be associated Exclusively with the Right Hemisphere. Similarly, No Scientific Evidence Validates the idea that analysis and logic depend on the left hemisphere, or that the left hemisphere is the special seat for arithmetic or reading. Dehaene (1997) found that the two hemispheres are active when identifying Arab numerals (e.g. 1 or 2 or 5).






Other studies show that, when the components of reading processes are analysed (e.g. decoding written words or recognising sounds for the higher level processes, such as reading a text), Sub-systems of the Two Hemispheres Are Activated.





Even a capacity associated essentially with the right hemisphere – encoding spatial relationships – proves to be within the Competence of the two hemispheres; but in a different way in each case. The left hemisphere is more skilful at encoding “categorical” spatial relationships (e.g. high/low or right/left), while the right hemisphere is more skilful at encoding metric spatial relationships (i.e. continuous distances).





Brain Imaging has shown that even in these two specific cases, areas of both hemispheres are activated and working together. A more surprising finding, perhaps, is that the dominant hemisphere for language is not necessarily connected to right- or left-handedness, as had been thought. A widespread idea is that right-handed people have their language on the left and vice versa, but 5% of right-handed people have the main areas related to language in the right hemisphere and nearly a third of left-handed people have them located in the left hemisphere.








Based on the latest studies, therefore, scientists think that the hemispheres of the brain do not work separately but together for all cognitive tasks, even if there are functional asymmetries. As a highly integrated system, it is rare that one part of the brain works individually. There are some tasks – such as recognising faces and producing speech – that are dominated by a given hemisphere, but most require that the two hemispheres work at the same time.


This invalidates the “left brain” and “right brain” concepts. Even if they may have brought some benefit through supporting more diversified educational methods, classifying students or cultures according to a dominant brain hemisphere is highly dubious scientifically, potentially dangerous socially, and strongly questionable ethically. It is thus an important myth to avoid.

"Understanding the Brain", The Birth of a Learning Science, 2007, page 117

Have We Two Brains? (4)

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“Is There One ‘Left-Brain’ & Another ‘Right-Brain’?” (4)
Since the 70s, Arise More Neuromyths About the "Split Brain"

This set of findings ([1], [2]) was ripe for spawning neuromyths. In 1970, Robert Ornstein’s "The Psychology of Consciousness" hypothesised that “Westerners” use mainly the left half of their brain with a well-trained left hemisphere thanks to their focus on language and logical thinking.However, they neglect their right hemisphere and, therefore, their emotional and intuitive thinking. Ornstein associates the left hemisphere with the logical and analytical thinking of “Westerners” and the right hemisphere with emotional and intuitive “Oriental” thinking.The traditional dualism between intelligence and intuition is thus accorded a “Physiological Origin”, based on the difference between the two hemispheres of the brain. Apart from the highly questionable ethical aspect of Ornstein’s ideas, they are the accumulated result of misinterpretations and distortions of available scientific findings.






Another widespread notion, without scientific foundation, stipulates that the left hemisphere tends to process quick changes and analyses the details and characteristics of the stimuli, while the right processes the simultaneous and general characteristics of the stimuli.This model remains entirely speculative. Starting from the differences between the verbal hemisphere (the left) and the non-verbal hemisphere (the right), a growing number of abstract concepts and relationships between mental functions and the two hemispheres has made their appearance on the neuromyth stage, moving further and further away from the scientific findings.







Gradually, further myths emerged in which the two hemispheres are associated not just with two ways of thinking but as revelations of two types of personality. The concepts of “left brain thinking” and “right brain thinking”, together with the idea of a dominant hemisphere, led to the notion that each individual depends predominantly on one of the two hemispheres, with distinctive cognitive styles. A rational and analytical person could be characterised as “left-brained”, an intuitive and emotional person as “right-brained”






The idea that “Western Societies” focus on only half of our mental capacities (“our left brain thinking”) and neglect the other half (“our right brain thinking”) became widespread, and some educationists and systems jumped on the bandwagon to recommend that schools change their teaching methods according to the dominant hemisphere concept.








Educators like M. Hunter and E.P Torrance claimed that educational programmes were principally made for “left brains” and favour left brain-dependent activities like always sitting in class or learning algebra, instead of favouring the right hemisphere by allowing students to stretch out and learn geometry. Hence, methods were devised which sought to engage the two hemispheres, or even to emphasise activities related to the right hemisphere. Such an example is “show and tell”: instead of just reading texts to the students (left hemisphere action), the teacher also shows images and graphs (right hemisphere actions). Other methods use music, metaphors, role-playing, meditation, or drawing, all to activate the synchronisation of the two hemispheres. Arguably, they have served to advance education by diversifying its methods. Nevertheless, insofar as they have borrowed on theories of the brain, they are based on scientific misinterpretation as the two halves of the brain cannot be so clearly separated.

"Understanding the Brain", The Birth of a Learning Science, 2007, page 116

(To be continued...)

Have We Two Brains? (3)

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“Is There One ‘Left-Brain’ & Another ‘Right-Brain’?” (3)
The 60s, Studying the “Split Brain Alive”

Until the 1960s, methods for observing the dominant role of the left hemisphere in language use and processing (lateralisation of language) were based on studies postmortem of patients with brain lesions. Some neurologists nevertheless claimed that language might not be entirely a left hemisphere function in that it was impossible to conclude no role for the right hemisphere on the basis of lack of lesions there among those who had had language impairments. Lesions only on the left side could be random.






The pertinence of this intuition was underlined by studies carried out on “split-brain” patients.The corpus callosum of these patients was severed in order to stop epileptic attacks from one hemisphere to the other.While the primary goal of the operation was to reduce epileptic fits, it also allowed researchers to study the role of each hemisphere on these patients.






The first such studies were conducted in the 1960s and 1970s, with Medicine Nobel Prize winner Roger Sperry and his team from the California Institute of Technology playing a dominant role.

They succeeded in supplying information to a single hemisphere in their “split-brain” patients and asked them to use each hand separately to identify objects without looking at them.
This experimental protocol built on the fact that basic sensory and motor functions are symmetrically divided between the two hemispheres of the brain - the left hemisphere receives almost all sensory information from and controls movements to the right part of the body and vice versa.Sensory information from the right hand is received in the left hemisphere and that from the left hand in the right hemisphere.

When patients touched an object with their right hand, they could easily name the object but not when they touched it with the left hand. Here was proof that the left hemisphere is the seat of principal language functions.




This unequal localisation of language functions created the idea of the left hemisphere as the verbal one and the right hemisphere as the non-verbal one. Since language has often been perceived as the noblest function of the human species, the left hemisphere was declared “Dominant".






Other experiments with the same type of patients helped to clarify the role of the right hemisphere. A video made by Sperry and Gazzaniga about the split-brain patient W.J. gives a surprising demonstration of the superiority of the right hemisphere for spatial vision. The patient was given several dice, each with two red sides, two white sides, and two sides with alternating white and red diagonal stripes. The task of the patient was to arrange the dice according to patterns presented on cards. The beginning of the video shows W.J. quickly arranging the dice in the required pattern using his left hand (controlled, remember, by the right hemisphere). He had great difficulty, however, completing the same task using his right hand – he was slow and moved the dice indecisively. Once his left hand intervenes, he became quick and precise but when the researchers hold it back he again became indecisive.

Other research by Roger Sperry et al. (1969) confirmed the domination of the right hemisphere in spatial vision. This role was then confirmed by clinical case studies. Patients suffering from lesions in the right hemisphere were not able to recognise familiar faces; other patients had difficulty with spatial orientation.

Some patients with lesions in the right hemisphere have shown defects in identifying the emotional intonation of words and in recognising emotional facial expressions. Behavioural studies back up the clinical studies: speech rhythms are best perceived when the sounds are received by the left ear so that the information goes to the right hemisphere and images seen by the left visual field provoke greater emotional reaction. It was deduced from this that the right hemisphere was also specialised in the processes related to emotions.

"Understanding the Brain", The Birth of a Learning Science, 2007, page 115

(To be continued...)

Have We Two Brains? (2)

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“Is There One ‘Left-Brain’ & Another ‘Right-Brain’?” (2)
A Myth that Began in the 19th Century

This “left brain/right brain” opposition originated in the First neurophysiology research. Intellectual capacities were often then described in two classes: critical and analytical aptitudes, on the one hand, and creative and synthetic aptitudes, on the other.



One of the major doctrines of neurophysiology from the 19th century associated each class to a hemisphere. In 1844, Arthur Ladbroke Wigan published A New View of Insanity: Duality of the Mind. He describes the two hemispheres of the brain as independent, and attributes to each one its own will and way of thinking: they usually work together but in some diseases they can work against each other.


This idea caught the imagination with the publication of Robert Louis Stevenson’s famous The Strange Case of Doctor Jekyll and Mister Hyde in 1866 which exploits the idea of a cultivated left hemisphere that opposes a primitive and emotional right hemisphere, which easily loses all control.



Paul Broca, a French neurologist, went beyond fiction to localise different roles in the two hemispheres. In the 1860s, he examined postmortem the brains of more than 20 patients whose language functions had been impaired. In all the brains examined, he noticed lesions in the frontal lobe of the left hemisphere, whereas the right hemisphere was still intact. He concluded that the Production of spoken language had to be located in the front part of the left hemisphere.



This was completed a few years later, by the German neurologist Carl Wernicke who also examined postmortem brains of those who had had language development disorders; he suggested that the capacity to Understand language is situated in the temporal lobe of the left hemisphere.

Thus, Broca and Wernicke associated the same hemisphere of the brain, the left, to two essential components of processing language – comprehension and oral production.

Brain Autopsy



Diagram of the Left Cerebral Hemisphere



Photograph of the Left Hemisphere "Normal"



Photograph of the Left Hemisphere "With the Damaged Broca's Area"

"Understanding the Brain", The Birth of a Learning Science, 2007, page 114, 115

(To be continued...)