The Wages of Sinistrality: Handedness, Brain Structure and Human Capital Accumulation

Abstract

Left-and right-handed individuals have different brain structures, particularly in relation to language processing. Using five data sets from the US and UK, I show that poor infant health increases the likelihood of a child being left-handed. I argue that handedness can thus be used to explore the long-run impacts of differential brain structure generated in part by poor infant health. Even conditional on infant health and family background, lefties exhibit economically and statistically significant human capital deficits relative to righties. Compared to righties, lefties score a tenth of a standard deviation lower on measures of cognitive skill and, contrary to popular wisdom, are not over-represented at the high end of the distribution. Lefties have more emotional and behavioral problems, have more learning disabilities such as dyslexia, complete less schooling, and work in less cognitively intensive occupations. Differences between left-and right-handed siblings are similar in magnitude. Most strikingly, lefties have six percent lower annual earnings than righties, a gap that can largely be explained by these differences in cognitive skill, disabilities, schooling and occupational choice. Lefties work in more manually intensive occupations than do righties, further suggesting that lefties' primary labor market disadvantage is cognitive rather than physical. Those likely be left-handed due to genetics show smaller or no deficits relative to righties, suggesting the importance of environmental shocks as the source of disadvantage. Handedness provides parents and schools a costlessly observable characteristic with which to identify young children whose cognitive and behavioral development may warrant additional attention. * For their very helpful comments, I am grateful to Caroline Hoxby, Ed Glaeser, Amitabh Chandra and Felipe BarreraOsorio, as well as participants in the NBER Education Group meetings and the Harvard Kennedy School Faculty Seminar. Colin Sullivan and Heather Sarsons provided outstanding research assistance. Finally, I thank my left-handed wife, Anna Lumelsky, for encouraging this work even when the coefficients troubled her. All errors are my own.

Fractionating negative and positive affectivity in handedness: Insights from the Reinforcement Sensitivity Theory of personality

“…These authors used Carver and White's BIS/BAS questionnaire which does not isolate BAS-Reward Interest. However, it may be pertinent to mention that there are a number of reports indicating that left-handedness is associated with higher earnings (Denny & Sullivan, 2007;Goodman, 2012;Ruebeck, Harrington, Moffitt, 2007) and or socio-economic status (Faurie, Golberg, Hercberg & Raymond, 2008;Faurie, Llaurens, Hegay & Raymond, 2012) although the effects appear to be moderated by sex/gender and/or level of education.…”

Competitiveness, Gender and Handedness: A Large-Sample Intercultural Study

“…Lefties have also been found to be overrepresented in male-dominated professions such as architects (Peterson and Lansky, 1974), mathematically oriented scientists (Temple, 1990), chess players (Coren, 1993) and U.S. presidents. 8 Goodman (2014), in an attempt to reconcile these disparate results, combines five datasets from the UK and the US and finds that, on average, left-handers earn less and have lower human capital.…”

“…Other determinants of left-handedness are genes and differential brain structures caused by stressors during pregnancy or birth(Goodman 2014). 7 The ratio of the length of the index finger to the length of the ring finger (2D:4D), which is established in utero, has been used extensively as a marker for the strength of prenatal hormone exposure (seeManning, 2002, for an introduction).…”

Employment Relations and Wages: What Can We Learn from Subjective Assessments?

“…It has also provided the framework for understanding the relationship between earnings and a host of other factors, including nonwage job characteristics (Duncan and Holmlund 1983); marriage (Korenman andNeumark 1991, 1992); computer use (Krueger 1993, DiNardo andPischke 1997); handedness (Goodman 2012); religion (Chiswick 1983, Tomes 1984; "locus of control" (Coleman andDeLeire 2003, Cebi 2007); personality traits (Gensowski 2013); beauty (Hamermesh and Biddle 1994); and sleep (Biddle and Hamermesh 1990), among many others. This paper uses the Mincer wage function framework to explore what can be learned from responses to two novel survey questions that were included in the 2000 wave of the Swedish Standard of Living Survey (or, LNU).…”