Lana Karasik and her colleagues also departed from previous research by observing babies in their home environment rather than in a psychology lab. Specifically, a researcher local to each of the six cultures visited 12 mother and baby pairs in their homes for one hour. These sessions were taped and coded later based on where the babies were (i.e. in their mothers arms, on the ground, or on baby or adult furniture), their body position (sitting or lying etc) and how close their mother was to them. The mothers didn't know that the study was about infant sitting ability.
Overall, one third of the infants were able to sit independently, defined as sitting without support for at least one second. But there was significant cross-cultural variation. For example, just two of the US infants displayed independent sitting and none of the Italian infants, compared with 8 of the Kenyan infants (67 per cent) and 11 of the Cameroonian infants (92 per cent). There was also a wide-range of sitting proficiency, in terms of how long infants sat independently in a single bout. For example, the shortest bout was 2.4 seconds, while the longest was 28 minutes (achieved by a Cameroonian baby).
|Figure from Karasik et al, 2015.|
It's tempting to infer that the cultural parenting practices in Kenya and Cameroon may have encouraged some of the infants in those cultures to acquire more precocious sitting abilities (on average). But of course this was a purely observational study with small samples, and we can't know whether the infants' abilities influenced their parents' behaviour or vice versa (in fact, it's probably a bit of both). It's also important to note, as the researchers do, that there was a huge amount of overlap in sitting ability across the cultures (e.g. some US infants sat independently longer than some Kenyan and Cameroonian infants), and there is also a large amount of variation within the cultures. Because of this, Karasik and her team say it is inappropriate to talk of babies in some cultures being uniformly more precocious than babies in others.
Infant sitting is a very important skill – it frees their hands to explore objects and interact more easily with adults. Given this, it seems amazing that most of what we know about the development of sitting ability is based on dated, lab-based research conducted almost exclusively in Western countries. "Had we not looked beyond onset ages [the simplistic idea that a child is either a sitter or not], ventured outside the laboratory, and studied samples of infants from six cultures across the globe," the researchers said, "we would never have known that at five months, some infants can safely sit on high benches for extended periods without the support of adults nearby."
Karasik, L., Tamis-LeMonda, C., Adolph, K., & Bornstein, M. (2015). Places and Postures: A Cross-Cultural Comparison of Sitting in 5-Month-Olds Journal of Cross-Cultural Psychology, 46 (8), 1023-1038 DOI: 10.1177/0022022115593803
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Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.
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