The fact that children learn new words and concepts fast and seemingly without effort has lead to a long controversy on how they succeed in this task. For example, it has been suggested that humans are born with a “language gene”. In her dissertation in phonetics, Eeva Klintfors, the Department of Linguistics, Stockholm University, has studied over three hundred 3- to 20-month-old Swedish infants. The children were exposed to animated images displayed on a screen while they heard words embedded in phrases. Since infants cannot label word-object connections at this age, an infrared camera recorded their eye movements directed towards the objects.

“The dissertation studies show that infants can learn the shape, color and other characteristics of objects after a very short presentation only. It is fascinating to see how infants direct their gaze towards the requested object despite the fact that we used a nonsense language in the experiments”, says Eeva Klintfors, who has created an artificial language called “Swenglish”. The words and phrases have the same structure as in Swedish, but the semantic content of the words is eliminated.

Early language acquisition takes place in close interaction with others, and it is typical that parents, other adults, and even older children repeat words and show the same object again and again – which helps the infant to combine these sensory impressions. One of the studies in the dissertation shows especially the importance of repetitions and other characteristics typical for child-directed-speech for the ability to build sound-meaning associations.

“From an adult’s perspective infants do strange things. My 4-year-old daughter had a period when she correctly inflected verbs, for example “go-went”. But now she has stopped that and says instead “go-goed”. But I am in the lucky position to know that this kind of U-shaped learning (from correct via incorrect back to the correct form) is common”, says Eeva Klintfors.

That the adult perspective may be inappropriate is shown in another study in Eeva Klintfors’ dissertation: infants combined sensory impressions based on whatever was most salient. When a sound was played the children’s gaze concentrated at images of the most prominent mouth movements. Children make often wrong associations between words and objects, but this does not have to be a problem. They also easily change strategy, always open for new suggestions.

“Flexibility seems to be very important for acquisition of concepts and words. We have observed similar tendencies in other mammals such as gerbils (desert rats) studied by our American colleagues. Gerbils may act based on an evolutionary ability that ensured survival when combining sounds with dangerous events”, says Eeva Klintfors.

An exciting extension of this dissertation within an EU project implements these findings in a humanoid robot. As the robot can acquire words by the above means, it can already be speculated that a “language gene” is not a prerequisite of word-learning.

Dissertation title: Emergence of words: Multisensory precursors of sound-meaning associations in infancy

The dissertation may be downloaded as pdf on

More information
Eeva Klintfors, Department of Linguistics, Stockholm University, phone +46 (0)70-716 95 04, +46 (0)8-16 19 32, e-mail

A portrait photo of Eeva Klintfors may be acquired from the university press office,, +46 (0)8 16 40 90.

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