Children learn sound systems really early

Building on earlier research about children and habituation to linguistic environment,

The results demonstrate that at 18 months children have a rudimentary understanding of the 'sound system' of their language and that knowledge guides their interpretation of the sounds they encounter," said Daniel Swingley, assistant professor in the Department of Psychology at Penn who worked with colleagues from the University of British Columbia and the Max-Planck-Institute for Psycholinguistics.
"Children can easily hear how the same word can be pronounced in different ways. We might say, 'Is that your kiiiiiitty"' or, 'Show me the kitty.' In English, we're still talking about the same cat. But children have to figure this out. In other languages, like Japanese or Finnish, those two versions of "kitty" could mean completely different things. Our study showed that 18-month-olds have already learned this and apply that knowledge when learning new words.

Apart from the linguistic interest, it also seems to have implications for learning more generally: that we are constantly learning and at subconscious levels we pick up all sorts of patterning things and integrate them into our perceptual approaches.
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