How the brains of men and women differ is a topic that fills bookshelves. Just as provocative is the question of whether the differences are predominantly hardwired or learned. On one side of the discussion is the argument from inherited biology; on the other is the argument from social and cultural influence. As with most debates involving nature and nurture, it’s far from clear whether biology or culture has the upper hand.
Researchers from the International Institute for Applied Systems Analysis in Vienna recently took a different approach to the question by starting with cognitive differences women and men are known to have, and then asking what role economic prosperity and social factors play in shaping those differences.
Researchers analyzed data culled from interviews with 14,000 women and 17,000 men, ages 50-84, which were conducted as part of the European Survey of Health initiative from 2006 to 2007. Participants lived in 13 countries spanning a range of economic, social and public health conditions in northern Europe, central Europe and southern Europe.
Each country in the study was assigned a regional development index (RDI) that benchmarked a combination of gross domestic product (GDP), education levels, life expectancy and infant mortality rates. Changes in RDI for each country were plotted across the lives of the study participants, thereby showing the economic, social and public health conditions these individuals were exposed to from birth onward.
The interviews evaluated three areas of cognitive performance: (1) episodic memory (the ability to recall words); numeracy (the ability to reason with basic mathematical concepts); and category fluency (the ability to name examples from categories). Typically men outperform women in numeracy and women outperform men in episodic memory. The genders are about even in category fluency.
This study showed similar test results: women did as well or better on episodic memory tests for every geographic region and across age groups. Likewise, men outperformed women on numeracy in every region and age group. Category fluency performance showed negligible differences.
These results were as expected, but when RDI was factored in, a remarkable and less expected result emerged: improvements in RDI for each country correlated with cognitive performance improvements for both genders -- but significantly more so for women.
Better developed countries, particularly those in northern Europe (followed in line by central Europe and southern Europe) showed the most cognitive improvements for both genders over time. But women clearly benefited more as RDI increased, both in episodic memory and numeracy. Women between the ages of 50-54 in northern Europe showed especially notable improvements.
The results may indicate that economic and social development opens more opportunities for women than men, possibly because women often begin at a position of greater disadvantage and have more to gain from RDI improvements. Quoting from the study: "These changes take place as a result of women gaining more than men from societal improvements over time, thereby increasing their general cognitive ability more than men."
Whether or not that explanation nails the cause of the changes, what seems clear is that economic and social factors strongly influence cognitive performance. Even if men and women do biologically inherit certain cognitive strengths and weaknesses, this study suggests that our societal influences play an enormous role in how potently those strengths and weaknesses are expressed, and how they change over time.
The study was published in the Proceedings of the National Academy of Sciences.
You can find David DiSalvo on Twitter @neuronarrative and at his website The Daily Brain. His latest book is Brain Changer: How Harnessing Your Brain’s Power To Adapt Can Change Your Life.
