Although our bodies appear largely symmetrical on the outside, the way our brains are organised and wired is rather more lop-sided. This is obvious to us in relation to handedness, whereby the brain is better at controlling one hand than the other. The idea that, for many of us, the left-hemisphere is dominant for language is also widely known. However, functional asymmetry between the brain hemispheres also affects our behaviour in more subtle ways that are still being explored. The latest example of this comes from Japan where Matia Okubo has shown that right-handers have a preference for sitting to the right of the cinema screen, but only when they are motivated to watch the film. The finding is consistent with the idea that in right-handers, the right-hemisphere is dominant for processing visual and emotional input. By sitting to the right of the screen, the film is predominantly processed by the right-hemisphere and the suggestion is that, without necessarily realising it, right-handers are choosing to sit in an optimal position for their brain to digest the movie.

Okubo presented 200 students with a grid showing the seats available in a cinema (a central area was shown as occupied; the screen was at the top of the grid). In the first experiment, all the students were told that the film was enjoyed by friends and critics, with half also told that the story was sad and depressing and to imagine that they’d rather avoid seeing it. For students who only heard the recommendation, the right-handers were far more likely to choose a seat to the right of the screen (74 per cent did so), whereas the left-handers and mixed-handers didn’t show a bias for one side or the other.

For the students who were put off the film, none showed a preference for the right-hand seats, regardless of their handedness. This suggests that we only choose an optimal seat for our brain organisation when we’re motivated to watch the film. Left-handers and mixed-handers are known to have a more balanced distribution of function across their hemispheres so this could explain why they didn’t show the opposite bias to the right-handers.

A second experiment was nearly identical, but this time half the students were told the film was excellent and depressing, whereas the other students were simply told they wouldn’t enjoy it. Again, when they were motivated to watch the film, even a depressing one, the right-handers showed a bias for seats to the right of the screen. ‘People tend to adopt the most effective manner in which their hemispheric functions can be utilised,’ Okubo said, adding that: ‘It is tempting to think that some other undiscovered behavioural asymmetries can also be discovered through this approach’.

This new research comes after a past study showed that adults with a more artistic, less analytic thinking style (associated with the right hemisphere) were more likely to sit on the right-hand side of the classroom; and another that showed people are more likely to exhibit the left side of their face (controlled by the right hemisphere) when asked to express emotion in a family photo, but to show their right profile when asked to pose as a scientist.

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Okubo, M. (2010). Right movies on the right seat: Laterality and seat choice. Applied Cognitive Psychology, 24 (1), 90-99 DOI: 10.1002/acp.1556

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Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.