Brain & cognition

Brain and Cognition xxx (2011) xxx–xxx

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Brain and Cognition
journal homepage: www.elsevier.com/locate/b&c

Mental rotation does not account for sex differences in left–right confusion
Sebastian Ocklenburg a,⇑, Marco Hirnstein b, Hanno Andreas Ohmann a, Markus Hausmann b
a b

Department of Biopsychology, Faculty of Psychology, Ruhr-UniversityBochum, D-44780 Bochum, Germany Department of Psychology, Durham University, South Road, Durham DH1 3LE, United Kingdom

a r t i c l e

i n f o

a b s t r a c t
Several studies have demonstrated that women believe they are more prone to left–right confusion (LRC) than men. However, while some studies report that there is also a sex difference in LRC tasks favouring men, others report thatmen and women perform equally well. Recently, it was suggested that sex differences only emerge in LRC tasks when they involve mental rotation. That is, sex differences that are reported for some LRC tasks are strongly affected by the well-documented male advantage in mental rotation. To test this assumption, 91 participants were investigated on two LRC tasks: The Left–Right Commands Task and theBergen Left–Right Discrimination Test. Additionally, participants were asked to complete an LRC self-rating questionnaire. To rule out the possibility that sex differences in LRC are confounded by sex differences in mental rotation, male and female participants were matched for mental rotation performance, resulting in a sample of 46 matched participants. These matched participants showed robust sexdifferences in favour of men in all LRC measurements. This suggests that pronounced sex differences in LRC are a genuine phenomenon that exists independently of sex differences in mental rotation. Ó 2011 Elsevier Inc. All rights reserved.

Article history: Accepted 28 January 2011 Available online xxxx Keywords: Left–right confusion Left–right discrimination Mental rotation Spatial cognitionSex differences Gender differences

1. Introduction Left–right confusion (LRC) is a common phenomenon experienced by many humans in various situations. Apart from anecdotal evidence, a number of scientific studies reported that healthy adults sometimes experience difficulty when telling left from right (Harris & Gitterman, 1978; McMonnies, 1990; Wolf, 1973). Particularly women believe themselves tobe more prone to LRC than men when they are asked to self-assess their ability to make fast and accurate left–right judgements (Hannay, Ciaccia, Kerr, & Barett, 1990; Hirnstein, Ocklenburg, Schneider, & Hausmann, 2009; Jaspers-Feyer & Peters, 2005; Jordan, Wüstenberg, JaspersFeyer, Fellbrich, & Peters, 2006). However, whether sex differences in self-ratings have behavioural consequences remainsunclear as some studies report lower accuracy (Bakan & Putnam, 1974; Ofte, 2002; Ofte & Hugdahl, 2002b) and slower reaction times in LRC tasks (Snyder, 1991) in women compared with men, while others report no sex differences (Teng & Lee, 1982; Williams, Standen, & Ricciardelli, 1993). Jordan et al. (2006) suggest that the conflicting results in LRC can be explained by sex differences in specificspatial abilities. For example, in the Bergen Left–Right Discrimination Test (Ofte, 2002; Ofte & Hugdahl, 2002a, 2002b), participants have to mark either the left or right hand of stickman figures that were are
⇑ Corresponding author. Fax: +49 234 32 14377.
E-mail address: sebastian.ocklenburg@rub.de (S. Ocklenburg). 0278-2626/$ - see front matter Ó 2011 Elsevier Inc. All rights reserved.doi:10.1016/j.bandc.2011.01.010

drawn either from the front or from the back. Performance in this task may be influenced by the fact that participants have to mentally rotate figures that are shown from the front to make a left– right decision. Mental rotation refers to the ability to mentally rotate two- or three-dimensional objects. Typically, men outperform women in tasks of mental rotation by effect...