Handedness as a major determinant of functional cradling bias

Abstract

Cradling is an interactive activity, involving a manual component that is very often an integral part of cradling. Cradling, while doing something else with the free hand, is referred to here as functional cradling. This study examined the relationship between a person's handedness and what arm he or she prefers to use when functionally cradling a baby doll that resembles a newborn infant. A total of 765 participants took part in the experiment, 403 women and 362 men, between the ages of 4 and 86 years. Left- and mixed-handers were actively recruited. The sample consisted of 64.3% right-handed, 24.7% mixed-handed, and 11.0% left-handed participants. The results showed a clear tendency for participants to cradle in their non-dominant arm (p < .001). Furthermore, this tendency increased with age and it was present in both sexes, although significantly stronger in women than in men. On the other hand, experience with young children through younger siblings and/or being a parent did not increase the likelihood to cradle in the non-dominant arm. It is concluded that humans have a clear functional cradling preference for the non-dominant arm because this enables the dominant arm to engage in other tasks. This might also explain why previous studies have reported a universal left cradling bias because a right-handed majority (intuitively) keeps the dominant hand free when cradling.

What is the Significance of Leftward Cradling Bias?

“…The hemispheric dominance hypothesis for maternal cradling bias should stipulate that left-handed mothers "intuitively" cradle their infants to the right arm. The results of the study by van der Meer and Husby [39] leave the question of hemispheric influences that support maternal cradling bias unclear because the situations that were under investigation were those where the cradler was dividing attention between infant and other activity, rather than an interaction with the infant alone.…”

“…This was investigated further in a study of functional cradling by van der Meer and Husby [39]. According to these researchers, "functional" cradling is the act of cradling an infant in the non-dominant arm while at the same time keeping the dominant hand free to complete functional tasks [39]. In their study, the relationship between hand dominance and directional functional cradling was observed with 765 participants.…”

“…The authors concluded that the data supported a hemispheric dominance hypothesis as the main influencing factor to account for left-ward cradling bias. The researchers surmised from their data that leftward cradling bias occurred with such frequency because this particular positioning of an infant would "intuitively" keep the dominant hand of the individual free to complete other tasks [39]. Weaknesses of the study lay in the selection of participants, a majority of which were right-handed or ambidextrous and the use of a life-like doll as opposed to a live infant.…”

“…It is a reasonable assumption that hemispheric dominance would influence the act of cradling a new-born baby as a majority of the population exhibit right-handedness, a trait that is reflective of left-hemispheric dominance. This was investigated further in a study of functional cradling by van der Meer and Husby [39]. According to these researchers, "functional" cradling is the act of cradling an infant in the non-dominant arm while at the same time keeping the dominant hand free to complete functional tasks [39].…”

“…In their study, the relationship between hand dominance and directional functional cradling was observed with 765 participants. Van der Meer and Husby [39] actively recruited left and mixed-handed participants for their experiment however; right-handed individuals comprised 64.3% of the cohort, while 24.7% were "mixed" handed. The left-handed participants made up 11% of the sample.…”