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From thought to language
Communicating in Words

HelpLink : Language and the brain

The Complementarity of the Brain’s Two Hemispheres

Words have an affective function as well as an informative one. Memories do not become fixed biologically unless there is an emotion associated with them. If someone asks you to talk about yourself, you will do so largely in terms of the emotions caused by your relationships with family, friends, and other persons.

Women prefer to talk about how they feel, while men prefer to discuss impersonal subjects. For women, speaking is most of all a way of relating to other people, while for men, it is more a way of transmitting information.

For example, in a study of 6609 people in five European countries, 66% of the women were the main users of the telephones in their households, while 76% of the men were the main users of the computers. This pattern supports the idea that women prefer personal subjects while men prefer external ones.

Women also make more frequent use of the word “I” as well as of social words related to persons, while men make more use of “we” and show more interest in objects and events.


Being able to speak means being able to produce sounds that are recognized by a group as conveying meaning according to established conventions. Hence a language is a finite system of units of sound that are combined in a specific order to form words. These words serve as symbols that are arbitrarily related to objects. And combining these words into sentences makes it possible to convey an infinite variety of information.

Though language is often regarded as indissociable from thought, it is still important to distinguish the two. Thought refers to the ability to have ideas and to infer new ideas from old ones. Language represents a different ability: the ability to encode ideas into signals for the purpose of communicating.

The most common form of language is oral communication, in which spoken words are used to express ideas. The basic components of oral language are called phonemes - elementary units of sound that are combined in various sequences to form morphemes. A morpheme is the smallest sequence of phonemes that can carry a meaning that can be isolated in a sentence in any given language. A morpheme is not the same thing as a syllable: some morphemes are shorter than one syllable, while others are longer. For example, in the word "kitchenette" there are two morphemes: "kitchen", which is two syllables long and the suffix "-ette", which is one syllable long and conveys the meaning "little".

By combining these phonemes and morphemes, we can construct as many words as we like (what we call the "dual articulation" of language). We can then combine these words with one another to produce a potentially infinite number of sentences.

The lexicon of a language is the set of all words in that language, its vocabulary. The syntax is the way that these words are used, the rules of grammar that enable words to be correctly assembled into sentences.

But most of all, language is an extremely powerful tool that remains very closely related to thought, because it enables us to represent—to “render present”, to evoke—things that exist only in our imaginations, or that are real but are simply elsewhere in space or time. This is the realm of semantics: the way that complex combinations of sounds or words successfully convey meaning.

The processes of understanding and producing language thus require the simultaneous mastery of lexical, syntactic, and semantic skills.

The advent of modern writing could even be said to have introduced yet another level of articulation, because it requires phonemes to be translated into letters or combinations of letters. Once communities developed systems of writing, they could transmit their knowledge more easily from one generation to the next. Cultural evolution accelerated and facilitated the growth of the arts and sciences. The information that defined our species no longer was passed on through our genetic code alone, but also through cultural codes that were handed down from generation to generation.

Though men may tend not to talk very much in intimate situations, they can become quite voluble in public. Apparently, the reason that men tend to speak more and for a longer time in public than women do is that doing so offers a good opportunity to acquire or confirm their social status. In contrast, women seem to prefer to express themselves in the private sphere, which affords greater opportunities to convey emotions.

Link : La guerre des sexes


Link : LANGAGE ORALLink : De 10 à 18 mois, ils chantent ou ils parlentLink : A partir de 18 mois, la poussée lexicaleLink : Le développement du langage
Link : Les conquérants du langageLink : Développement du langageLink : Speech and Language: Developmental MilestonesLink : Language Development In Children

When a child begins to talk, its conversation is directed at other people, of course, but also at itself. Piaget and Vygotsky called this second type of language “egocentric discourse”, and children appear to use it to “think out loud”. It is a sort of monologue in which children seem to explain their actions to themselves, often after having completed them.

This egocentric discourse, however, seems to gradually become internalized when the child is 3 to 5 years old. Once this discourse has become completely internal, children have learned not only how to talk with words, but also how to think with them.

Link : Lev Vygotski : Pédagogue et penseur de notre temps

A number of studies have attempted to establish a connection between gestures and words (studies involving mirror neurons, for example). Another study has shown that performative gestures demonstrating the transition from intention to attention can be observed in babies 9 to 13 months old. Starting at 14 months of age, articulate language, for which the gestures laid the groundwork, takes over from them. There thus appears to be a continuity between gestures and spoken words.

Suppose a mother gives her child a new pair of shoes, and then somebody telephones the home, speaks to the child, and asks him what he just got. The child’s reaction will depend on his age. At age 3, all children will try to show their new shoes to the telephone. At age 4, all or almost all children will use words instead of the object itself.

Children will often go on to elaborate, perhaps saying that the shoes are a pretty colour, or that it was nice of Mommy to buy them, and so on. In this way, children begin to use words to act on the mental images and the inner world of the person with whom they are talking.


Around the end of their first year of life, children realize that they have their own inner psychic landscapes and that they can share them with other people. At that point children become part of the world of intersubjectivity, in which they no longer respond solely to stimuli from the inside, such as hunger, or from the outside, such as their parents’ smiles, but also to their own conception of other people’s mental worlds.

Children at this stage have understood that words are used not just to produce a pleasant flow of sounds, but are actually symbols used to designate things, often things that are absent. Thus children are no longer stuck with tangible reality. They can form their own representation of the world.

This is the psychic context in which children speak their first words. Their very first words will refer to the people on whom children imprint (Mommy, Daddy, Grandma, etc.). Next come words about the objects in their daily lives. Only after that come words about objects that are absent to the children themselves and absent to other people.

It is around the age of 10 months that a baby usually says its first word, usually “mama” or“dada”, scarcely distinguishable from the babble around it. A small word for an adult, but a considerable achievement for the baby, who has thus come quite a long way since the moment its parents’ sperm and egg cells met.

At age 1, the baby knows a handful of words, and at age 18 months, from 30 to 50. Of course, every child develops its vocabulary at its own pace, with the process generally accelerating so that the child knows over 100 words at 21 months and over 200 at 2 years.

Approximate number of words in a child’s vocabulary from birth to age 3. Note the exponential learning curve during these first years of life.

During this period of lexical development, children express themselves with individual words in isolation or with groups of two or three words. These first words are often actually sentences contracted into a single word, because they do not refer solely to an object, but to an action or a situation. To interpret these word/sentences properly, you have to know the context in which they are being used. But gradually, children’s use of words becomes freed from the present context. Children develop the concept of object permanence and become able to form a mental image of something without having it there in front of them.

At age 2, children have a nearly complete understanding of the language they hear, and when they want something, they ask for it by formulating a request orally. Children’s first two- or three-word sentences begin to follow rules of syntax, but do not include pronouns or articles, and their use of verbs is simplified (French-speaking children, for example, still use only the infinitive form).

From age 2 to age 5, children master the syntax of their mother tongue. They do so without ever learning the rules explicitly, but simply through exposure to the regular structures in other people’s speech. One proof of this process is that the errors that children make at this stage are very regular as well. For example, having observed that most English verbs form the past tense through the addition of the sound “-ed”, a child might say “I goed” instead of “I went”.

At about age 3, children’s distortions of words have disappeared almost completely, and the basic subject-verb-object syntactic structure is in place. Their vocabulary now includes nearly 1000 words, and they have mastered the use of the pronoun “I”. Children at this age love listening to stories and asking questions and are starting to tell about things that they have seen or done.

At about age 4, children’s words come in a torrent, composed largely of incessant questions. Children can now talk about the concept of time (yesterday, today, and tomorrow), and they make more and more use of prepositions. Thus, at age 4, the primary components of language are normally in place, and so it is at this age that specific language disorders can be detected.

At age 5, relative pronouns and conjunctions appear. Children can conjugate verbs and in general handle language more subtly, even though some minor imperfections persist. Children also learn to say things in a way that is more appropriate to the context. They acquire this ability as they gain some distance from their own perceptions and realize that other people do not necessarily see the world the same way they do.

At age 6, children use more and more nouns, verbs, and adjectives. Their vocabulary now totals over 2500 words.

Despite some variations from child to child, the average age at which these various language abilities are acquired and the sequence in which they are acquired remain constant from one culture to the next. Another thing common to all cultures is that the ability to learn another language diminishes considerably after puberty.

Children acquire the sense of being themselves at the age of about 5 months, well before they learn to speak. Their emerging use of language, however, depends on two things: their neurological maturation, and their cultural and linguistic environment.

For example, when a child is 3 or 4 years old, the word “dead” means what happens when he points his finger at an adult and says “Bang! Bang!”: the adult makes a face, falls on the floor, and stops moving. By the time this child is 5 or 6, though, his nervous system has matured enough for him to begin to imagine people and things being very distant physically. “Dead” now means a state of someone’s being very far away somewhere, for a long, long time. Somewhere between the ages of 7 and 10, connections form in the child’s brain between the prefrontal lobe, which is responsible for anticipation, and the limbic system, which manages memories. Now the child can understand the concept of time, and the word “dead” refers to something absolute. Thus it takes seven to 10 years for this word to acquire its “adult” meaning.

This maturation of language is also affected by genetic and environmental constraints. For instance, a child who loses her mother at an early age may experience an accelerated maturation of the word “dead” and understand it completely by age 4 or 5. Conversely, children who grow up in an environment that is so safe and free of any frightening ideas as to be almost stifling may remain attached to a very childish conception of the word “dead” for a longer time. Thus language maturation depends on both endogenous and exogenous factors.


Link : Brain imaging reveals new language circuitsLink : L'association québécoise des personnes aphasiquesLink : Mémoire et aphasieLink : La musique peut-elle aider à récupérer la parole?
Link : USING PET TOWARD A NATURALIZED MODEL OF HUMAN LANGUAGE PROCESSINGLink : The Neuroscience of LanguageLink : Language Pathologies

Rethinking the Role of Broca’s Area in Language

According to some experts, the Wernicke-Geschwind model accords too much importance to certain sharply defined areas of the cortex —Broca’s and Wernicke’s areas— whereas increasingly, it is being found that the severity of Broca’s and Wernicke’s aphasias depends on the extent of the cortex affected by the lesion outside of these areas.

Certain subcortical structures not represented in the Wernicke-Geschwind model, such as the thalamus and the caudate nucleus, can also influence aphasia. Strokes that damage both cortical and subcortical structures result in more serious impairments than strokes that damage cortical structures only.

Lastly, the fact that stroke patients often recover a substantial portion of their language functions also indicates that other parts of the brain may compensate for those that have been destroyed.

In people with Broca’s aphasia, the inability to communicate is often accompanied by other deficits caused by the damage to the left frontal lobe. Paralysis of the right side of the body is the most common example. This paralysis may be severe (hemiplegia) or slight (hemiparesis).

Another deficit sometimes observed is apraxia, in which the individual cannot perform certain movements voluntarily but can perform these same movements automatically (for example, they may be able to lick an ice cream cone without thinking about it but not be able to stick out their tongue at will).

In some cases, the left frontal lobe damage may affect vision, causing hemianopsia—the loss of part of the field of vision.

All of these problems accompanying Broca’s aphasia mean that in addition to requiring language re-education, the patient may need physiotherapy and occupational therapy.

Studies of brain lesions can provide valuable insights into the mechanics of the brain’s cognitive systems. For example, such studies have shown that music and language are dissociable. Thus some aphasics can sing a song such as “Blue Moon” but not can’t speak the word “moon” in isolation or identify the moon by its name when they see it up in the sky.


There are various types of language disorders, and they fall into two major categories: those related to development (dysphasia) and those resulting from acquired brain damage (aphasia).

The types of dysphasia that are the least serious and the easiest to treat are the articulation disorders: errors in the movements of the mouth and tongue that are used to produce phonemes. Most often, these errors involve consonants (for example, when a child makes the “d” sound in place of the “t”).

Lisping (pronouncing “s” as “th”) is another example of an articulation disorder. Still others include completely omitting a sound (saying “adio” instead of “radio”) or replacing one phoneme with another (saying “tat” instead of “cat”). Articulation disorders do not interfere greatly with children’s ability to make themselves understood, but can expose them to ridicule and thus make them unhappy.

Speech delays are another category of dysphasia. They can be caused, for example, by a child’s not perceiving certain sounds properly in certain words, even though he or she is not deaf. In such cases it can be very hard for the child to reproduce these words accurately. For instance, the child may say “shobel” for “shovel” or “pease” for “please”.

Other forms of dysphasia involve disorders in the syntactic component of language. Normally, this component becomes established naturally around age 3. But children age 4 or 5 who have this disorder still use incorrect grammar, speak telegraphically, use personal pronouns improperly, or fail to use the correct forms of verbs.

The language problems associated with dysphasia are not insurmountable: they often resolve themselves without therapeutic intervention, but the children concerned will generally be late in speaking and their language will generally retain, to varying degrees, some signs of the initial disorder.

One particular kind of dysphasia, dyslexia, produces difficulties in reading.

Link : La dysphasieLink : Mot par mot : la dysphasie 


Aphasia patients who retain a good understanding of language and are motivated to learn to speak again have a good prognosis for recovering their use of language. They may continue to show improvement for nearly three years after the accident that caused their impairment. On the other hand, if they have shown no improvement three months after the accident, then the prognosis is fairly poor.


Anosognosia is a condition in which patients deny their impairment, be it motor-related (for example, hemiplegia), memory-related (such as amnesia), or language-related (such as aphasia). For example, patients with Wernicke’s aphasia may be unaware that their speech is disorganized or that they are having any trouble in understanding other people when they speak. The fact that such patients “do not know that they do not know” makes communicating with them more complicated.


The two most common general forms of aphasia are Broca’s aphasia and Wernicke’s aphasia. They are named after the two neurologists who, toward the end of the 19th century, described two different locations in the brain where lesions caused distinct types of language deficits.

Broca’s aphasia (also known as motor aphasia or expressive aphasia) occurs as the result of lesions to Broca’s area in the left frontal lobe. People with Broca’s aphasia search for words and speak slowly, in a telegraphic manner. For example, if you ask someone with Broca’s aphasia “Could you explain what you are doing in hospital?”, he or she might respond, “Yes. Of course. Me go, um, uh, nine o’clock, speak… two times…read…wri…, um, write…practice… make prog…-ress.”

People with Broca’s aphasia mainly use words that have content, while experiencing difficulty with those that have only a syntactic function (articles, pronouns, and conjunctions) and with the endings of various verb tenses. These people also have trouble in distinguishing the subject from the object in sentences couched in the passive voice, such as “The student is congratulated by the teacher.” The combined result of all these problems in people with Broca’s aphasia is to significantly impair their ability to engage in spontaneous oral communication.

People with Broca’s aphasia sometimes also suffer from apraxia, or from partial paralysis of the right side of the body (see sidebar). This may have something to do with the fact that Broca’s area is located close to other areas with motor functions in the posterior portion of the frontal lobe.

In people with Broca’s aphasia, understanding of language is generally fairly well preserved. This is not the case for people with the other common form of aphasia, Wernicke’s.

Lesions that cause Wernicke’s aphasia (also known as sensory aphasia or receptive aphasia) occur in the posterior portion of the superior temporal lobe in the dominant cerebral hemisphere, generally the left. These lesions reduce understanding of spoken and written language, because this part of the brain plays a critical role in the relationship between the recognition of a word and its meaning. Responses to simple instructions, such as “Place object A on top of object B” show that, unlike patients with Broca’s aphasia, those with Wernicke’s do not understand what is being asked of them. They can read such an instruction correctly, but cannot then perform the action indicated by the meaning of the words.

When Wernicke’s aphasics speak, their language is littered with jargon, made-up terms, and other incomprehensible words. Their grammar is often intact, but they misuse so many words that conversation with them is very difficult and somewhat reminiscent of Chomsky’s famous sentence, “Colorless green ideas sleep furiously”.

If you ask someone with Wernicke’s aphasia “What brought you into the hospital?”, he or she might answer, “Well, I sweat, I’m terribly nervous, you know, from time to time, I can’t move any more, whereas, on the other hand, you know what I mean, I have to get a move on, look at everything that’s happening, and all the rest with it.” Another Wernicke’s patient, when asked to describe a tortoise, replied, “a torpedo, a frammis that goes in the garden.”
Thus Wernicke’s aphasics speak a strange mixture of clarity and nonsense, yet do so at a very fluent pace.

Wernicke’s aphasics do not usually have any of the motor neurological impairments, such as hemiplegia, that may affect Broca’s aphasics.

In addition to Broca’s and Wernicke’s aphasias, several other forms of aphasia have been described.

Research : Sheila Blumstein's researchLink : Les aphasiesLink : AphasieLink : Qu'est-ce que l'aphasie ?
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