Behavioural biases to one side are interesting to psychologists. They are an example of exceptions to the general rule of symmetry in biological development. The placement of language-related brain areas is another exception. Babies’ head turning bias is the first behavioural bias to occur in humans, and may be related to handedness bias, which in turn is related to the language-area asymmetry in the brain.
Mindhacks.com readers will remmeber our report of Paul Rozin’s call for more observational reports in psychology. Perhaps he’d approve of this 2003 paper in Nature: Adult persistence of head-turning asymmetry.
Onur Güntürkün observed adult head turning behaviour among kissing couples in the U.S, Germany and Turkey. Sure enough, his observational research, in ‘international airports, large railway stations, beaches and parks’ discovered that during most kisses (64% of the sample) couples turned their heads to the right rather than the left. A statistically significant difference and, according to Güntürkün, ‘a surprising romantic reappearance’ in later life of the neonatal head turning bias.
So, next time you hold a child in your arms and they turn their head to the right, you are seeing an echo of a bias that may be directly linked to our species’ most remarkable evolutionary achievement, language, and a bias that stays with us throughout our lives.
Reference: Gunturkun, O. (2003). Human behaviour: Adult persistence of head-turning asymmetry. Nature, 421(6924), 711. doi:10.1038/421711a which contains the line ‘It takes two people to kiss (Fig. 2)’!