A large new study has challenged long-held beliefs about the relationship between handedness (being left- or right-handed) and spatial navigation abilities. Contrary to conventional wisdom, the study, which recruited millions of participants from around the world, found no significant difference in spatial skills between left-handers and right-handers. The research was recently published in Proceedings of the Royal Society B: Biological Sciences.
For years, scientists have been intrigued by the idea that our dominant hand might be linked to our spatial abilities. Some theorized that brain lateralization, the phenomenon where specific cognitive functions are predominantly localized in one hemisphere of the brain, might play a role in the relationship between handedness and spatial abilities.
Some studies had previously suggested that left-handers might have an advantage in spatial tasks. However, these studies were often limited in size and scope, leaving room for doubt. This new study sought to address these gaps by using a vast dataset collected through a mobile video game to investigate whether handedness truly influences spatial skills.
“The initial push for exploring this research question really came from my collaborators Hope Oloye, Antoine Coutrot, and Hugo Spiers. Regarding my own personal interest, cognitive differences between left-handers and right-handers is a topic that is quite big in the popular imagination, so I guess it has always been in the back of my mind,” explained study author Pablo Fernandez-Velasco, a British Academy postdoctoral fellow at the University of York.
“From a more scientific perspective, there is a connection between handedness and patterns of lateralization in the brain. That is, functions (e.g. language comprehension) that tend to be preferentially located on one hemisphere rather than the other. So learning about the connection between handedness and function (in this case spatial cognition) can also tell us, indirectly, about the connection between lateralization and function.”
“Testing the connection between handedness and navigation ability is quite difficult, because you need a large cross-cultural sample. Using big data, we were finally able to establish that, in fact, there is no association between handedness and navigation ability.”
The researchers embarked on an ambitious endeavor to collect data from millions of participants worldwide. To do this, they employed a mobile app called Sea Hero Quest. Participants downloaded and played the game, with the motivation being to contribute to research by having fun and playing a game. Notably, there was no financial compensation involved.
The advertising campaign for the project was extensive, involving partnerships with organizations like Saatchi and Saatchi Ltd., Deutsche Telekom, and Alzheimer’s Research UK. Social media, press releases, and media coverage contributed to making Sea Hero Quest the most downloaded app on the Apple App store for a brief period. This strategic approach allowed the researchers to recruit over 4 million participants from around the world.
From this vast pool of participants, the researchers carefully selected a subset for their analysis. They excluded those who had not provided all their demographics and participants over 70 years old due to potential selection bias. They also limited the analysis to countries with at least 1,000 players. Finally, they excluded participants who had not completed the first 11 levels of the game. This resulted in a final sample of 422,772 participants, across 41 different countries.
To assess spatial navigation abilities, the researchers focused on specific levels within the Sea Hero Quest game. Participants had to navigate a virtual boat to reach designated goal locations on a map. By analyzing the participants’ trajectories and performance on these levels, the researchers calculated a wayfinding performance metric for each individual, serving as a measure of their spatial navigation ability.
Contrary to earlier suggestions that left-handed individuals might have a spatial advantage, the study’s findings showed no significant difference in spatial navigation ability between left-handers and right-handers.
Fernandez-Velasco outlined two important takeaways from the research: “The first one is the potential of big data and gamefied experiments in psychological research. Particularly when it comes to questions that involve a lot of variables, such as demographics, gender effects, cultural effects, etc. The second one is the one in the title [‘No link between handedness and spatial navigation’]. Whether or not you are left-handed makes no difference about how good you are at finding your way!”
Additionally, the study uncovered variations in the prevalence of left-handedness among countries. For example, the Netherlands had the highest rate of left-handedness, while China had the lowest. Interestingly, the effect of handedness on spatial abilities did not vary significantly across countries, suggesting that this finding was consistent on a global scale. Furthermore, task difficulty did not appear to influence the relationship between handedness and spatial performance.
Fernandez-Velasco told PsyPost he was surprised “how consistent the finding was across cultures. Even when you add potential mediating factors to the analysis, you get no effect. For instance, is there maybe an interaction between task difficulty and handedness that affects navigation performance? Maybe left-handers are a bit better than right-handers when faced with more difficult navigation challenges? As it turns out, even then, there is no effect.”
The study’s strength lies in its massive and diverse sample size, which allowed for robust conclusions. But like all research, there are some limitations. The study relied on self-reported dominant hand information, which might not capture the full spectrum of an individual’s handedness. Future research could explore more comprehensive measures of handedness.
“There are a few caveats,” Fernandez-Velasco said. “The main one is that one could explore the same question using more detailed questionnaires about handedness that explore things like degree of left-handedness. There are also people who are left-handed when it comes to playing guitar, but right-handed to writing. We use a single, fairly straightforward question to measure handedness, but one could look at more fine-grained differences and see if there is some connection to spatial cognition there. Future work that explores this in more detail would be very valuable.”
“Make sure to download Sea Hero Quest and give it a try!” the researcher added. “It is a fun video game, and it helps advance really important research.”
The study, “No link between handedness and spatial navigation: evidence from over 400 000 participants in 41 countries“, was authored by P. Fernandez-Velasco, A. Coutrot†, H. Oloye, J. M. Wiener, R. C. Dalton, C. Holscher, E. Manley, M. Hornberger, and H. J. Spiers.
