Are we getting more intelligent? That’s a question I’m sure we would all like to assume to be answered with a “Yes”. However is there any proof of this?
Well it turns out that in Sweden there has been an ongoing study doing intelligence tests on 70 year olds and the findings do actually show that, yes the 70 year olds of today do perform better in these tests than their predecessors of thirty years ago.
And there are probably a number of contributing factors such as • Improved pre and neonatal care • Improved nutrition • Better quality of education • Better treatment of hypertension and other vascular diseases • Higher intellectual requirements of today’s society with access to advanced technology, the Internet and television.
But that wasn’t the main reason for conducting this study. What the researchers were looking for was to see if they could find a better way to predict who is most likely to develop dementia and whether the early symptoms have changed over recent generations.
One thing that the study did reveal too is that the incidence of dementia has remained unchanged over this period of 30 years. People aged 70 to 75 today have the same incidence of dementia as those of that age group 30 years ago. This is important because with the expected explosion of people likely to be diagnosed with Alzheimer’s disease over the next forty years, it would be possible to assume that Alzheimer’s is becoming more common. The increase is actually simply a reflection of the larger proportion of people in our society reaching that age.
In this study of over 2000 people the only predictor of dementia was found to be those with memory problems. But not all of those with memory problems went on to develop dementia.
The researchers were looking to identify those at risk of developing dementia and while they found pointers for a group born in 1901-1902 the same tests did not reveal any clues for the generation born in 1930. It is hoped that finding earlier signs of dementia will enable people more at risk to get diagnosed earlier and receive support more quickly.
S. Sacuiu, D. Gustafson, M. Sjogren, X. Guo, S. Ostling, B. Johansson, I. Skoog. Secular changes in cognitive predictors of dementia and mortality in 70-year-olds. Neurology, 2010; 75 (9): 779 DOI: 10.1212/WNL.0b013e3181f0737c