Children begin to learn to count earlier than previously thought, according to new research.
Professor Virginia Slaughter of the University of Queensland, and colleagues from Japan and the United Kingdom, assessed how babies responded to videos of counting, and found a dramatic cognitive shift by the time they reached 18 months of age.
The researchers tested children by showing them videos of either correct sequential counting of six fish, or of two fish alternately being counted up to six.
The research published in Biology Letters found that 15-month-olds were equally interested in both the correct and incorrect counting, but that 18-month-olds showed far more interest in the correct counting sequence.
"Our study is new because we have shown that babies, long before they can start to count themselves, can recognise a fundamental principle of counting: that every single object must be counted for counting to be happening correctly," says Slaughter.
Commenting on the research, Dr Evan Kidd from the School of Psychological Sciences at La Trobe University in Melbourne says children generally begin to acquire words at a rapid rate at about 18 months old.
"So having a handle on the number words, which is a basic requirement in the task, would provide them with a big advantage over 15-month-olds who were struggling to access or even decode the number sequence."
In another experiment, the researchers tested whether language comprehension was important. For children of English speakers, they counted the sequence in Japanese, while for Japanese babies, they counted it in English.
In each case, babies showed far more interest in counting in their native language.
"What that is telling you is that they are learning from exposure to counting events. When it's a familiar routine that they know and they recognise those words, they also recognise when that routine is disrupted," says Slaughter.
University of Melbourne's Professor Bob Reeve, who studies the development of mathematical reasoning in children, says it is an important paper that will influence research in the field.
"It suggests that the older (18 month) infants had acquired understanding of a major counting principle, prior to being able to use count words … it highlights the interaction between cultural, linguistic factors and principled knowledge in cognitive development."
Count me in
And what can parents take out of it? Slaughter says a 15-month-old child will enjoy you counting with them.
"Babies really do like counting - they care about it," she says. "Something is going on in their little brains that's extracting the abstract rules that govern counting.
"The more exposure they have to counting, the more likely they are to be on track to understanding how it works."
The researchers are now planning to test whether early understanding of the principles of counting translates into better mathematical ability later in life.