Are only infants held more often on the left? If so, why? Testing the attention-emotion hypothesis with an infant, a vase, and two chimeric tests, one “emotional,” one not

ABSTRACT

Most adults, especially women, hold infants and dolls but not books or packages on the left side. One reason may be that attention is more often leftward in response to infants, unlike emotionally neutral objects like books and packages. Women's stronger bias may reflect greater responsiveness to infants. Previously, we tested the attention hypothesis by comparing women's side-of-hold of a doll, book, and package with direction-of-attention on the Chimeric Faces Test (CFT) [Harris, L. J., Cárdenas, R. A., Spradlin, Jr., M. P., & Almerigi, J. B. (2010). Why are infants held on the left? A test of the attention hypothesis with a doll, a book, and a bag. Laterality: Asymmetries of Body, Brain and Cognition, 15(5), 548–571. doi:10.1080/13576500903064018]. Only the doll was held more often to the left, and only for the doll were side-of-hold and CFT scores related, with left-holders showing a stronger left-attention bias than right-holders. In the current study, we tested men and women with a doll and the CFT along with a vase as a neutral object and a “non-emotional” chimeric test. Again, only the doll was held more often to the left, but now, although both chimeric tests showed left-attention biases, scores were unrelated to side-of-hold. Nor were there sex differences. The results support left-hold selectivity but not the attention hypothesis, with or without the element of emotion. They also raise questions about the contribution of sex-of-holder. We conclude with suggestions for addressing these issues.

KEYWORDS:

• Side-of-hold
• infants
• attention
• emotion
• sex-of-holder

Acknowledgments

We are grateful to the two anonymous reviewers for their helpful suggestions, comments, and questions.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 The former include Sri Lanka (Bruser, 1981), Bali (Harris, Jentoft, & Almerigi, 2002), and Brazil and Venezuela (Bolton, 1978); the latter include Korea (Harris, Kang, & Almerigi, 2003), Japan (Negayama, Kawai, Yamamoto, Tomiwa, & Sakakihara, 2010), France (Donnot & Vauclair, 2007), England (Reissland et al., 2009), Norway (van der Meer & Husby, 2006), Sweden (de Château, 1983), South Africa (Saling & Cooke, 1984), Canada (Almerigi, Van Hooren, Bulman-Fleming, & Harris, 2002), and the United States (e.g., Dagenbach et al., 1988).

2 The Pool consists of approximately 2000 students enrolled in courses offering credit or extra credit for participation. Students can choose from as many as 25 online and laboratory studies and are recruited through an online Research Participation System. Because women normally outnumber men in psychology courses, we oversampled men to make the numbers more nearly equal.

3 After completing the first test, subjects were instructed to remove the picture from the towel and to replace it with the picture for the second test.

4 The original scale had 25 items. Following Peters’ recommendation, we deleted three items, bat baseball, sweep with broom, use large shovel, that in his study failed to differentiate right- from left-handed writers.

5 Because not all 482 subjects completed all tests (e.g., 12 incompletes for the infant test, 6 for the vase test, 1 for the handedness questionnaire), the number of subjects in the analyses varied slightly.

6 We checked to see how the percentages would change if we assigned mixed-handers to the left- or right-handed subgroups based on the hand used for writing. Of 23 mixed-handers, 14 reported always or mostly using the left. Adding them to the left-handed subgroup raised the percentage from 7% to 9.9%, which is virtually identical to the figure in other surveys. Seven reported always or mostly using the right. Adding them to the right-handed subgroup raised the figure to 88.4%. The remaining two subjects reported writing with either hand.

Additional information

Funding

During the conduct of this study, Nathaniel D. Stewart was supported by a Provost's Undergraduate Research Initiative Award from Michigan State University.