This study suggests that pupils are better at faster but less complex answers
Today's 14-year-old pupils are better at quick-fire answers, but much worse at complex questions than teenagers in the 1970s, research suggests.
Professor Michael Shayer of King's College London looked at how 800 secondary pupils performed in problem-solving tests.
He said his findings reflected that pupils now lived in an environment favouring instant responses.
But the downside was a "dumbing down" and a lack of deeper understanding.
Professor Shayer says that the tests studied two levels of knowledge - one which required quick, descriptive responses - and in such questions today's 14-year-olds were better than their predecessors who had taken the same tests in 1976.
However, when it came to a higher level of understanding, researchers found that today's pupils were much less successful than in the 1970s.
This could be described as a process of "dumbing down", says Professor Shayer, in which the culture of learning favours an instant, superficial way of handling information.
This also means that there is less emphasis on thinking more deeply and developing skills that provide a more substantial grasp of ideas and concepts, says Professor Shayer.
In terms of what has caused this shift, he points to the landscape of young lives.
"Everything in the past 30 years has speeded up. It's about reacting quickly but at a shallow level," says Professor Shayer.
He says that the culture of text messages and computer games is about speed and instant hits, rather than more profound or detailed ways of handling information.
He suggests that this decline in higher-level thinking means that many more pupils will be limited in their responses to subjects.
Professor Shayer's research is a follow-up to an earlier study in which he compared the performance of present day 11 and 12-year-old pupils with those taking the same test in the 1970s.
In that case, Professor Shayer found that despite Sats tests showing that pupils were improving, his research showed that pupils' achievements were lower than those taking the same test in the 1970s.
He estimated that these pupils in the first year of secondary school were at the equivalent level of learning of children two years younger in the 1970s.
He argues that improvements in Sats test results can operate separately from any objective measure of ability, because of the pressure put on schools and teachers to keep increasing their scores.
The need to get higher results means that teachers focus on the areas which will deliver improvements in grades, he says.
Therefore improvements do not mean any overall increase in pupils' ability to grasp concepts, he argues.
"Exam standards are rigorously maintained by independent regulators and more young people than ever before have now got a firm foundation for further education, apprenticeships or work based training," said a spokesperson from the DCSF.