In some countries, including China, people are more likely to report being right handed if they are educated beyond secondary school level or live in a country where there may be a stigma around left-handedness
Fewer than 3 per cent of people in China report being left-handed, despite the global average being closer to 10 per cent. Researchers think the difference is probably due to a continuing cultural stigma against left-handedness, which is less of an issue elsewhere, rather than genetics.
Hugo Spiers at University College London and his colleagues are overseeing a long-running study that assesses people’s ability to navigate using the mobile phone game Sea Hero Quest.
As part of this research, more than 400,000 people – aged 19 to 69 – in 41 countries have self-reported whether they are left or right-handed.
The researchers initially wanted to assess whether someone’s ability to navigate within a space is linked to being left or right-handed. Finding no link, they then used their large data set to gauge if certain factors, such as the country where a person lives or their level of education, influence whether we predominantly use our left or right hand.
In the study, 9.94 per cent of the participants said they were left-handed, similar to a 2020 meta-analysis that put the figure at 10.6 per cent. Why being right-handed is so much more common probably involves our genetics, among other potential factors, says Spiers. “It’s one of these major mysteries,” he says.
The researchers found that people in the Netherlands are the most likely to report being left-handed, at 12.95 per cent, followed by the United Arab Emirates, Israel and Puerto Rico. China, however, has the lowest reported rate at 2.64 per cent, followed by Indonesia, Vietnam and Hong Kong.
The difference between these two ends of the spectrum is probably not due to genetics, but instead influenced by cultural stigmas, says Spiers. Children in countries such as China may be told by teachers and their parents to use their right hand, perhaps due to a stigma around being left-handed, he says.
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In countries such as Indonesia and China, there is also a large number of children who are the first of their family to receive an education, the researchers write in their paper. In these recently industrialised countries it may be easier and more cost effective to teach everyone to write with the same hand and being right-handed is much more common, says Spiers.
In a 2013 paper, titled “Why are there (almost) no left-handers in China?”, Howard Kushner at Emory University, Georgia, similarly said that the number of first-generation children to receive an education, particularly in China, “has strained resources and required sustained conformity in order to teach students basic skills, especially to read and write”.
Spiers and his colleagues also found that in China, Indonesia, India, Taiwan and Hong Kong, people are less likely to identify as being left-handed if they are educated beyond secondary school level, compared with those who left the education system once they had completed secondary school.
These people may study or work in prestige places where being left or right-handed is noticed by others, says Spiers. “Cultural norms may mean this group are more influenced to change their handedness to conform to a social norm,” he says.
Only people with a mobile phone and internet access could take part in the study, and therefore the findings don’t represent the countries’ populations, says Spiers.
Nevertheless, Timothy Verstynen at Carnegie Mellon University, Pennsylvania, says the results reveal the role that cultural biases can play in people’s hand preferences. “But we still don’t really know why such a small percentage of people do prefer their left hands in the first place, beyond cultural factors,” he says.
Reference: bioRxivDOI: doi.org/10.1101/2023.03.30.534904