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On the other hand: including left-handers in cognitive neuroscience and neurogenetics


Left-handers are often excluded from study cohorts in neuroscience and neurogenetics in order to reduce variance in the data. However, recent investigations have shown that the inclusion or targeted recruitment of left-handers can be informative in studies on a range of topics, such as cerebral lateralization and the genetic underpinning of asymmetrical brain development. Left-handed individuals represent a substantial portion of the human population and therefore left-handedness falls within the normal range of human diversity; thus, it is important to account for this variation in our understanding of brain functioning. We call for neuroscientists and neurogeneticists to recognize the potential of studying this often-discarded group of research subjects.

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Figure 1: Hemispheric activation differences in left- and right-handers during action verb reading.
Figure 2: Language and visuospatial activations in left-handers with typical and atypical language lateralization.
Figure 3: Left- and right-handers show differences in lateralization during face perception.


  1. 1

    McManus, I. C. Right Hand, Left Hand (Phoenix, 2002).

    Google Scholar 

  2. 2

    Smits, R. The Puzzle of Left-Handedness (Reaktion Books, 2011).

    Google Scholar 

  3. 3

    Blau, A. Don't let your child be a lefty! Tri-City Herald (Washington) 38 (1961).

    Google Scholar 

  4. 4

    Oldfield, R. C. The assessment and analysis of handedness: the Edinburgh inventory. Neuropsychologia 9, 97–113 (1971).

    CAS  Article  PubMed  Google Scholar 

  5. 5

    Büsch, D., Hagemann, N. & Bender, N. The dimensionality of the Edinburgh Handedness Inventory: an analysis with models of the item response theory. Laterality 15, 610–628 (2010).

    Article  PubMed  Google Scholar 

  6. 6

    Dragovic, M. Towards an improved measure of the Edinburgh Handedness Inventory: a one-factor congeneric measurement model using confirmatory factor analysis. Laterality 9, 411–419 (2004).

    Article  PubMed  Google Scholar 

  7. 7

    Annett, M. Left, Right, Hand and Brain: The Right Shift Theory (Laurence Erlbaum, 1985).

    Google Scholar 

  8. 8

    Annett, M. Patterns of hand preference for pairs of actions and the classification of handedness. Br. J. Psychol. 100, 491–500 (2009).

    Article  PubMed  Google Scholar 

  9. 9

    Nicholls, M. E. R., Chapman, H. L., Loetscher, T. & Grimshaw, G. M. The relationship between hand preference, hand performance, and general cognitive ability. J. Int. Neuropsychol. Soc. 16, 585–592 (2010).

    Article  PubMed  Google Scholar 

  10. 10

    Triggs, W. J., Calvanio, R., Levine, M., Heaton, R. K. & Heilman, K. M. Predicting hand preference with performance on motor tasks. Cortex 36, 679–689 (2000).

    CAS  Article  PubMed  Google Scholar 

  11. 11

    Björk, T., Brus, O., Osika, W. & Montgomery, S. Laterality, hand control and scholastic performance: a British birth cohort study. BMJ Open 2, e000314 (2012).

    Article  PubMed  PubMed Central  Google Scholar 

  12. 12

    Badzakova-Trajkov, G., Häberling, I. S. & Corballis, M. C. Magical ideation, creativity, handedness, and cerebral asymmetries: a combined behavioural and fMRI study. Neuropsychologia 49, 2896–2903 (2011).

    Article  PubMed  Google Scholar 

  13. 13

    Somers, M., Sommer, I. E., Boks, M. P. & Kahn, R. S. Hand-preference and population schizotypy: a meta-analysis. Schizophr. Res. 108, 25–32 (2009).

    CAS  Article  PubMed  Google Scholar 

  14. 14

    Eckert, M. A. et al. Manual and automated measures of superior temporal gyrus asymmetry: concordant structural predictors of verbal ability in children. Neuroimage 41, 813–822 (2008).

    Article  PubMed  PubMed Central  Google Scholar 

  15. 15

    Groen, M. A., Whitehouse, A. J. O., Badcock, N. A. & Bishop, D. V. M. Does cerebral lateralization develop? A study using functional transcranial Doppler ultrasound assessing lateralization for language production and visuospatial memory. Brain Behav. 2, 256–269 (2012).

    Article  PubMed  PubMed Central  Google Scholar 

  16. 16

    Bryden, M. P., Roy, E. A., McManus, I. C. & Bulman-Fleming, M. B. On the genetics and measurement of human handedness. Laterality 2, 317–336 (1997).

    CAS  Article  PubMed  Google Scholar 

  17. 17

    Reiss, M., Tymnik, G., Kögler, P., Kögler, W. & Reiss, G. Laterality of hand, foot, eye, and ear in twins. Laterality 4, 287–297 (1999).

    CAS  Article  PubMed  Google Scholar 

  18. 18

    Elias, L. J. & Bryden, M. P. Footedness is a better predictor of language lateralisation than handedness. Laterality 3, 41–51 (1998).

    CAS  Article  PubMed  Google Scholar 

  19. 19

    Mcmanus, I. C. in Language Lateralization and Psychosis (eds Sommer, I. E. C. & Kahn, R. S.) 37–57 (Cambridge Univ. Press, 2009).

    Book  Google Scholar 

  20. 20

    Faurie, C. & Raymond, M. Handedness frequency over more than ten thousand years. Proc. R. Soc. Lond. B 271, S43–S45 (2004).

    Article  Google Scholar 

  21. 21

    Perelle, I. B. & Ehrman, L. An international study of human handedness: the data. Behav. Genet. 24, 217–227 (1994).

    CAS  Article  PubMed  Google Scholar 

  22. 22

    Hepper, P. G., McCartney, G. R. & Shannon, E. A. Lateralised behaviour in first trimester human foetuses. Neuropsychologia 36, 531–534 (1998).

    CAS  Article  PubMed  Google Scholar 

  23. 23

    Hepper, P. G. The developmental origins of laterality: fetal handedness. Dev. Psychobiol. 55, 588–595 (2013).

    Article  PubMed  Google Scholar 

  24. 24

    Hugdahl, K. & Davidson, R. J. The Asymmetrical Brain (MIT Press, 2004).

    Google Scholar 

  25. 25

    Hering-Hanit, R., Achiron, R., Lipitz, S. & Achiron, A. Asymmetry of fetal cerebral hemispheres: in utero ultrasound study. Arch. Dis. Child. Fetal Neonatal Ed. 85, F194–F196 (2001).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  26. 26

    Rogers, L. J. & Andrew, R. (eds) Comparative Vertebrate Lateralization (Cambridge Univ. Press, 2002).

    Book  Google Scholar 

  27. 27

    Hopkins, W. D. et al. Hand preferences for coordinated bimanual actions in 777 great apes: implications for the evolution of handedness in hominins. J. Hum. Evol. 60, 605–611 (2011).

    Article  PubMed  PubMed Central  Google Scholar 

  28. 28

    Gannon, P. J., Holloway, R. L., Broadfield, D. C. & Braun, A. R. Asymmetry of chimpanzee planum temporale: humanlike pattern of Wernicke's brain language area homolog. Science 279, 220–222 (1998).

    CAS  Article  PubMed  Google Scholar 

  29. 29

    Hopkins, W. D. et al. Gray matter asymmetries in chimpanzees as revealed by voxel-based morphometry. Neuroimage 42, 491–497 (2008).

    Article  PubMed  PubMed Central  Google Scholar 

  30. 30

    Lyn, H. et al. Planum temporale grey matter asymmetries in chimpanzees (Pan troglodytes), vervet (Chlorocebus aethiops sabaeus), rhesus (Macaca mulatta) and bonnet (Macaca radiata) monkeys. Neuropsychologia 49, 2004–2012 (2011).

    Article  PubMed  PubMed Central  Google Scholar 

  31. 31

    Corballis, M. C. From mouth to hand: gesture, speech, and the evolution of right-handedness. Behav. Brain Sci. 26, 199–208 (2003).

    PubMed  Google Scholar 

  32. 32

    Corballis, M. C., Badzakova-Trajkov, G. & Häberling, I. S. Right hand, left brain: genetic and evolutionary bases of cerebral asymmetries for language and manual action. Cogn. Sci. 3, 1–17 (2012).

    Google Scholar 

  33. 33

    Pinel, P. et al. Genetic variants of FOXP2 and KIAA0319/TTRAP/THEM2 locus are associated with altered brain activation in distinct language-related regions. J. Neurosci. 32, 817–825 (2012).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  34. 34

    Kos, M. et al. CNTNAP2 and language processing in healthy individuals as measured with ERPs. PLoS ONE 7, e46995 (2012).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  35. 35

    Kim, B. et al. The effects of the catechol-O-methyltransferase val158met polymorphism on white matter connectivity in patients with panic disorder. J. Affect. Disord. 147, 64–71 (2013).

    CAS  Article  PubMed  Google Scholar 

  36. 36

    Rose, E. J. et al. The effect of the neurogranin schizophrenia risk variant rs12807809 on brain structure and function. Twin Res. Hum. Genet. 15, 296–303 (2012).

    Article  PubMed  Google Scholar 

  37. 37

    Hibar, D. P. et al. Alzheimer's disease risk gene, GAB2, is associated with regional brain volume differences in 755 young healthy twins. Twin Res. Hum. Genet. 15, 286–295 (2012).

    Article  PubMed  PubMed Central  Google Scholar 

  38. 38

    Chen, J. et al. A combined study of genetic association and brain imaging on the DAOA gene in schizophrenia. Am. J. Med. Genet. B Neuropsychiatr. Genet. 162, 191–200 (2013).

    CAS  Article  Google Scholar 

  39. 39

    Sprooten, E. et al. An investigation of a genomewide supported psychosis variant in ZNF804A and white matter integrity in the human brain. Magn. Reson. Imag. 30, 1373–1380 (2012).

    CAS  Article  Google Scholar 

  40. 40

    Yang, X. et al. Impact of brain-derived neurotrophic factor Val66Met polymorphism on cortical thickness and voxel-based morphometry in healthy Chinese young adults. PLoS ONE 7, e37777 (2012).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  41. 41

    Li, Y. et al. Less efficient information transfer in Cys-allele carriers of DISC1: a brain network study based on diffusion MRI. Cereb. Cortex 23, 1715–1723 (2013).

    Article  PubMed  Google Scholar 

  42. 42

    Paulus, F. M. et al. Association of rs1006737 in CACNA1C with alterations in prefrontal activation and fronto-hippocampal connectivity. Hum. Brain Mapp. (2013).

  43. 43

    van der Heijden, C. D. C. C. et al. Genetic variation in ataxia gene ATXN7 influences cerebellar grey matter volume in healthy adults. Cerebellum 12, 390–395 (2013).

    Article  CAS  PubMed  Google Scholar 

  44. 44

    Nieto-Castañón, A. & Fedorenko, E. Subject-specific functional localizers increase sensitivity and functional resolution of multi-subject analyses. Neuroimage 63, 1646–1669 (2012).

    Article  PubMed  PubMed Central  Google Scholar 

  45. 45

    Hancock, R. & Bever, T. G. Genetic factors and normal variation in the organization of language. Biolinguistics 7, 075–095 (2013).

    Google Scholar 

  46. 46

    Townsend, D. J., Carrithers, C. & Bever, T. G. Familial handedness and access to words, meaning, and syntax during sentence comprehension. Brain Lang. 78, 308–331 (2001).

    CAS  Article  PubMed  Google Scholar 

  47. 47

    Tzourio-Mazoyer, N. et al. Left hemisphere lateralization for language in right-handers is controlled in part by familial sinistrality, manual preference strength, and head size. J. Neurosci. 30, 13314–13318 (2010).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  48. 48

    Tzourio-Mazoyer, N. et al. Effect of familial sinistrality on planum temporale surface and brain tissue asymmetries. Cereb. Cortex 20, 1476–1485 (2010).

    Article  PubMed  Google Scholar 

  49. 49

    Willems, R. M. & Casasanto, D. Flexibility in embodied language understanding. Front. Psychol. 2, 116 (2011).

    PubMed  PubMed Central  Google Scholar 

  50. 50

    Mahon, B. Z. & Caramazza, A. A critical look at the embodied cognition hypothesis and a new proposal for grounding conceptual content. J. Physiol. Paris 102, 59–70 (2008).

    Article  PubMed  Google Scholar 

  51. 51

    Willems, R. M. & Francken, J. C. Embodied cognition: taking the next step. Front. Cogn. Sci. 3, 582 (2012).

    Google Scholar 

  52. 52

    Willems, R. M. & Hagoort, P. Neural evidence for the interplay between language, gesture, and action: a review. Brain Lang. 101, 278–289 (2007).

    Article  PubMed  Google Scholar 

  53. 53

    Aziz-Zadeh, L., Wilson, S. M., Rizzolatti, G. & Iacoboni, M. Congruent embodied representations for visually presented actions and linguistic phrases describing actions. Curr. Biol. 16, 1818–1823 (2006).

    CAS  Article  PubMed  Google Scholar 

  54. 54

    Hauk, O., Johnsrude, I. & Pulvermuller, F. Somatotopic representation of action words in human motor and premotor cortex. Neuron 41, 301–307 (2004).

    CAS  Article  PubMed  Google Scholar 

  55. 55

    Willems, R. M., Hagoort, P. & Casasanto, D. Body-specific representations of action verbs: neural evidence from right- and left-handers. Psychol. Sci. 21, 67–74 (2010).

    Article  PubMed  Google Scholar 

  56. 56

    Willems, R. M., Toni, I., Hagoort, P. & Casasanto, D. Body-specific motor imagery of hand actions: neural evidence from right- and left-handers. Front. Hum. Neurosci. 3, 39 (2009).

    Article  PubMed  PubMed Central  Google Scholar 

  57. 57

    Hauk, O. & Pulvermüller, F. The lateralization of motor cortex activation to action-words. Front. Hum. Neurosci. 5, 149 (2011).

    Article  PubMed  PubMed Central  Google Scholar 

  58. 58

    Lewis, J. W., Phinney, R. E., Brefczynski-Lewis, J. A. & DeYoe, E. A. Lefties get it 'right' when hearing tool sounds. J. Cogn. Neurosci. 18, 1314–1330 (2006).

    Article  PubMed  Google Scholar 

  59. 59

    Longcamp, M., Anton, J. L., Roth, M. & Velay, J. L. Visual presentation of single letters activates a premotor area involved in writing. Neuroimage 19, 1492–1500 (2003).

    Article  PubMed  Google Scholar 

  60. 60

    Longcamp, M., Anton, J. L., Roth, M. & Velay, J. L. Premotor activations in response to visually presented single letters depend on the hand used to write: a study on left-handers. Neuropsychologia 43, 1801–1809 (2005).

    Article  PubMed  Google Scholar 

  61. 61

    Longcamp, M., Tanskanen, T. & Hari, R. The imprint of action: motor cortex involvement in visual perception of handwritten letters. Neuroimage 33, 681–688 (2006).

    CAS  Article  PubMed  Google Scholar 

  62. 62

    Willems, R. M. & Hagoort, P. Hand preference influences neural correlates of action observation. Brain Res. 1269, 90–104 (2009).

    CAS  Article  PubMed  Google Scholar 

  63. 63

    Hari, R. et al. Activation of human primary motor cortex during action observation: a neuromagnetic study. Proc. Natl Acad. Sci. USA 95, 15061–15065 (1998).

    CAS  Article  PubMed  Google Scholar 

  64. 64

    Casasanto, D. Embodiment of abstract concepts: good and bad in right- and left-handers. J. Exp. Psychol. Gen. 138, 351–367 (2009).

    Article  PubMed  Google Scholar 

  65. 65

    Casasanto, D. Different bodies, different minds the body specificity of language and thought. Curr. Dir. Psychol. Sci. 20, 378–383 (2011).

    Article  Google Scholar 

  66. 66

    De Nooijer, J. A., van Gog, T., Paas, F. & Zwaan, R. A. When left is not right: handedness effects on learning object-manipulation words using pictures with left- or right-handed first-person perspectives. Psychol. Sci. 24, 2515–2521 (2013).

    Article  PubMed  Google Scholar 

  67. 67

    Eling, P. Broca on the relation between handedness and cerebral speech dominance. Brain Lang. 22, 158–159 (1984).

    CAS  Article  PubMed  Google Scholar 

  68. 68

    Ettlinger, G., Jackson, C. V. & Zangwill, O. L. Cerebral dominance in sinistrals. Brain 79, 569–588 (1956).

    CAS  Article  PubMed  Google Scholar 

  69. 69

    Goodglass, H. & Quadfasel, F. A. Language laterality in left-handed aphasics. Brain 77, 521–548 (1954).

    CAS  Article  PubMed  Google Scholar 

  70. 70

    Hécaen, H., De Agostini, M. & Monzon-Montes, A. Cerebral organization in left-handers. Brain Lang. 12, 261–284 (1981).

    Article  PubMed  Google Scholar 

  71. 71

    Knecht, S. et al. Handedness and hemispheric language dominance in healthy humans. Brain 123, 2512–2518 (2000).

    Article  PubMed  Google Scholar 

  72. 72

    Szaflarski, J. P. et al. Language lateralization in left-handed and ambidextrous people: fMRI data. Neurology 59, 238–244 (2002).

    CAS  Article  PubMed  Google Scholar 

  73. 73

    Steinmetz, H., Volkmann, J., Jäncke, L. & Freund, H. J. Anatomical left–right asymmetry of language-related temporal cortex is different in left- and right-handers. Ann. Neurol. 29, 315–319 (1991).

    CAS  Article  PubMed  Google Scholar 

  74. 74

    Sommer, I. E. C., Ramsey, N. F., Mandl, R. C. W. & Kahn, R. S. Language lateralization in monozygotic twin pairs concordant and discordant for handedness. Brain 125, 2710–2718 (2002).

    CAS  Article  PubMed  Google Scholar 

  75. 75

    Bookheimer, S. Functional MRI of language: new approaches to understanding the cortical organization of semantic processing. Annu. Rev. Neurosci. 25, 151–188 (2002).

    CAS  Article  PubMed  Google Scholar 

  76. 76

    Price, C. J. The anatomy of language: a review of 100 fMRI studies published in 2009. Ann. NY Acad. Sci. 1191, 62–88 (2010).

    Article  PubMed  Google Scholar 

  77. 77

    Hagoort, P., Baggio, G. & Willems, R. M. in The Cognitive Neurosciences 4th edn (ed. Gazzaniga, M. S.) 819–836 (MIT Press, 2009).

    Google Scholar 

  78. 78

    Sperry, R. Some effects of disconnecting the cerebral hemispheres. Science 217, 1223–1226 (1982).

    CAS  Article  PubMed  Google Scholar 

  79. 79

    Van der Haegen, L., Cai, Q. & Brysbaert, M. Colateralization of Broca's area and the visual word form area in left-handers: fMRI evidence. Brain Lang. 122, 171–178 (2012).

    Article  PubMed  Google Scholar 

  80. 80

    Seghier, M. L., Kherif, F., Josse, G. & Price, C. J. Regional and hemispheric determinants of language laterality: implications for preoperative fMRI. Hum. Brain Mapp. 32, 1602–1614 (2011).

    Article  PubMed  Google Scholar 

  81. 81

    Tzourio-Mazoyer, N., Josse, G., Crivello, F. & Mazoyer, B. Interindividual variability in the hemispheric organization for speech. Neuroimage 21, 422–435 (2004).

    CAS  Article  PubMed  Google Scholar 

  82. 82

    Cai, Q., Van der Haegen, L. & Brysbaert, M. Complementary hemispheric specialization for language production and visuospatial attention. Proc. Natl Acad. Sci. USA 110, E322–E330 (2013).

    CAS  Article  PubMed  Google Scholar 

  83. 83

    Whitehouse, A. J. O. & Bishop, D. V. M. Hemispheric division of function is the result of independent probabilistic biases. Neuropsychologia 47, 1938–1943 (2009).

    Article  PubMed  PubMed Central  Google Scholar 

  84. 84

    Bryden, M. P., Hécaen, H. & DeAgostini, M. Patterns of cerebral organization. Brain Lang. 20, 249–262 (1983).

    CAS  Article  PubMed  Google Scholar 

  85. 85

    Badzakova-Trajkov, G., Häberling, I. S., Roberts, R. P. & Corballis, M. C. Cerebral asymmetries: complementary and independent processes. PLoS ONE 5, e9682 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  86. 86

    Króliczak, G., Piper, B. J. & Frey, S. H. Atypical lateralization of language predicts cerebral asymmetries in parietal gesture representations. Neuropsychologia 49, 1698–1702 (2011).

    Article  PubMed  PubMed Central  Google Scholar 

  87. 87

    Raymer, A. M. et al. Crossed apraxia: implications for handedness. Cortex 35, 183–199 (1999).

    CAS  Article  PubMed  Google Scholar 

  88. 88

    Goldenberg, G. Apraxia — the cognitive side of motor control. Cortex (2013).

  89. 89

    Vingerhoets, G. et al. Praxis and language are linked: evidence from co-lateralization in individuals with atypical language dominance. Cortex 49, 172–183 (2013).

    Article  PubMed  Google Scholar 

  90. 90

    Van den Berg, F. E., Swinnen, S. P. & Wenderoth, N. Involvement of the primary motor cortex in controlling movements executed with the ipsilateral hand differs between left- and right-handers. J. Cogn. Neurosci. 23, 3456–3469 (2011).

    Article  PubMed  Google Scholar 

  91. 91

    Kloppel, S. et al. The effect of handedness on cortical motor activation during simple bilateral movements. Neuroimage 34, 274–280 (2007).

    Article  PubMed  Google Scholar 

  92. 92

    Solodkin, A., Hlustik, P., Noll, D. C. & Small, S. L. Lateralization of motor circuits and handedness during finger movements. Eur. J. Neurol. 8, 425–434 (2001).

    CAS  Article  PubMed  Google Scholar 

  93. 93

    Dassonville, P., Zhu, X. H., Uurbil, K., Kim, S. G. & Ashe, J. Functional activation in motor cortex reflects the direction and the degree of handedness. Proc. Natl Acad. Sci. USA 94, 14015–14018 (1997).

    CAS  Article  PubMed  Google Scholar 

  94. 94

    Verstynen, T., Diedrichsen, J., Albert, N., Aparicio, P. & Ivry, R. B. Ipsilateral motor cortex activity during unimanual hand movements relates to task complexity. J. Neurophysiol. 93, 1209–1222 (2005).

    Article  PubMed  Google Scholar 

  95. 95

    Corballis, M. C. The Lopsided Ape: Evolution of the Generative Mind (Oxford Univ. Press, 1991).

    Google Scholar 

  96. 96

    Polk, T. A., Park, J., Smith, M. R. & Park, D. C. Nature versus nurture in ventral visual cortex: a functional magnetic resonance imaging study of twins. J. Neurosci. 27, 13921–13925 (2007).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  97. 97

    Yovel, G., Tambini, A. & Brandman, T. The asymmetry of the fusiform face area is a stable individual characteristic that underlies the left-visual-field superiority for faces. Neuropsychologia 46, 3061–3068 (2008).

    Article  PubMed  Google Scholar 

  98. 98

    Hamilton, C. R. & Vermeire, B. A. Complementary hemispheric specialization in monkeys. Science 242, 1691–1694 (1988).

    CAS  Article  PubMed  Google Scholar 

  99. 99

    Willems, R. M., Peelen, M. V. & Hagoort, P. Cerebral lateralization of face-selective and body-selective visual areas depends on handedness. Cereb. Cortex 20, 1719–1725 (2010).

    Article  PubMed  Google Scholar 

  100. 100

    Sun, T. et al. Early asymmetry of gene transcription in embryonic human left and right cerebral cortex. Science 308, 1794–1798 (2005).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  101. 101

    Ocklenburg, S., Beste, C. & Güntürkün, O. Handedness: a neurogenetic shift of perspective. Neurosci. Biobehav. Rev. 37, 2788–2793 (2013).

    Article  PubMed  Google Scholar 

  102. 102

    Medland, S. E. et al. Genetic influences on handedness: data from 25,732 Australian and Dutch twin families. Neuropsychologia 47, 330–337 (2009).

    Article  PubMed  Google Scholar 

  103. 103

    Medland, S. E. et al. Meta-analysis of GWAS for handedness: results from the ENGAGE consortium. Am. Soc. Hum. Genet. Abstr. [online], (2009).

  104. 104

    Armour, J. A. L., Davison, A. & McManus, I. C. Genome-wide association study of handedness excludes simple genetic models. Heredity (2013).

  105. 105

    Singleton, A. B., Hardy, J., Traynor, B. J. & Houlden, H. Towards a complete resolution of the genetic architecture of disease. Trends Genet. 26, 438–442 (2010).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  106. 106

    Francks, C. et al. LRRTM1 on chromosome 2p12 is a maternally suppressed gene that is associated paternally with handedness and schizophrenia. Mol. Psychiatry 12, 1129–1139 (2007).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  107. 107

    Francks, C. Leucine-rich repeat genes and the fine-tuning of synapses. Biol. Psychiatry 69, 820–821 (2011).

    Article  PubMed  Google Scholar 

  108. 108

    Ko, J., Fuccillo, M. V., Malenka, R. C. & Südhof, T. C. LRRTM2 functions as a neurexin ligand in promoting excitatory synapse formation. Neuron 64, 791–798 (2009).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  109. 109

    Linhoff, M. W. et al. An unbiased expression screen for synaptogenic proteins identifies the LRRTM protein family as synaptic organizers. Neuron 61, 734–749 (2009).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  110. 110

    Siddiqui, T. J., Pancaroglu, R., Kang, Y., Rooyakkers, A. & Craig, A. M. LRRTMs and neuroligins bind neurexins with a differential code to cooperate in glutamate synapse development. J. Neurosci. 30, 7495–7506 (2010).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  111. 111

    De Wit, J. et al. LRRTM2 interacts with Neurexin1 and regulates excitatory synapse formation. Neuron 64, 799–806 (2009).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  112. 112

    Südhof, T. C. Neuroligins and neurexins link synaptic function to cognitive disease. Nature 455, 903–911 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  113. 113

    DeLisi, L. E. et al. Hand preference and hand skill in families with schizophrenia. Laterality 7, 321–332 (2002).

    Article  PubMed  Google Scholar 

  114. 114

    Orr, K. G., Cannon, M., Gilvarry, C. M., Jones, P. B. & Murray, R. M. Schizophrenic patients and their first-degree relatives show an excess of mixed-handedness. Schizophr. Res. 39, 167–176 (1999).

    CAS  Article  PubMed  Google Scholar 

  115. 115

    Csernansky, J. G. et al. Abnormalities of thalamic volume and shape in schizophrenia. Am. J. Psychiatry 161, 896–902 (2004).

    Article  PubMed  Google Scholar 

  116. 116

    DeLisi, L. E. et al. Anomalous cerebral asymmetry and language processing in schizophrenia. Schizophr. Bull. 23, 255–271 (1997).

    CAS  Article  PubMed  Google Scholar 

  117. 117

    Kawasaki, Y. et al. Anomalous cerebral asymmetry in patients with schizophrenia demonstrated by voxel-based morphometry. Biol. Psychiatry 63, 793–800 (2008).

    Article  PubMed  Google Scholar 

  118. 118

    Oertel-Knöchel, V., Knöchel, C., Stäblein, M. & Linden, D. E. J. Abnormal functional and structural asymmetry as biomarker for schizophrenia. Curr. Top. Med. Chem. 12, 2434–2451 (2012).

    Article  PubMed  Google Scholar 

  119. 119

    Shenton, M. E., Dickey, C. C., Frumin, M. & McCarley, R. W. A review of MRI findings in schizophrenia. Schizophr. Res. 49, 1–52 (2001).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  120. 120

    Sommer, I., Ramsey, N., Kahn, R., Aleman, A. & Bouma, A. Handedness, language lateralisation and anatomical asymmetry in schizophrenia: meta-analysis. Br. J. Psychiatry J. Ment. Sci. 178, 344–351 (2001).

    CAS  Article  Google Scholar 

  121. 121

    Bailey, A. et al. Autism as a strongly genetic disorder: evidence from a British twin study. Psychol. Med. 25, 63–77 (1995).

    CAS  Article  PubMed  Google Scholar 

  122. 122

    Boles, D. B., Barth, J. M. & Merrill, E. C. Asymmetry and performance: toward a neurodevelopmental theory. Brain Cogn. 66, 124–139 (2008).

    Article  PubMed  Google Scholar 

  123. 123

    De Fossé, L. et al. Language-association cortex asymmetry in autism and specific language impairment. Ann. Neurol. 56, 757–766 (2004).

    Article  PubMed  Google Scholar 

  124. 124

    Herbert, M. R. et al. Abnormal asymmetry in language association cortex in autism. Ann. Neurol. 52, 588–596 (2002).

    Article  PubMed  Google Scholar 

  125. 125

    Herbert, M. R. et al. Brain asymmetries in autism and developmental language disorder: a nested whole-brain analysis. Brain J. Neurol. 128, 213–226 (2005).

    CAS  Article  Google Scholar 

  126. 126

    Deep-Soboslay, A. et al. Handedness, heritability, neurocognition and brain asymmetry in schizophrenia. Brain J. Neurol. 133, 3113–3122 (2010).

    Article  Google Scholar 

  127. 127

    Scerri, T. S. et al. PCSK6 is associated with handedness in individuals with dyslexia. Hum. Mol. Genet. 20, 608–614 (2011).

    CAS  Article  PubMed  Google Scholar 

  128. 128

    Arning, L. et al. PCSK6 VNTR polymorphism is associated with degree of handedness but not direction of handedness. PLoS ONE 8, e67251 (2013).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  129. 129

    Brandler, W. M. et al. Common variants in left/right asymmetry genes and pathways are associated with relative hand skill. PLoS Genet. 9, e1003751 (2013).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  130. 130

    McManus, I. C., Martin, N., Stubbings, G. F., Chung, E. M. K. & Mitchison, H. M. Handedness and situs inversus in primary ciliary dyskinesia. Proc. Biol. Sci. 271, 2579–2582 (2004).

    CAS  Article  PubMed  PubMed Central  Google Scholar 

  131. 131

    Tanaka, S., Kanzaki, R., Yoshibayashi, M., Kamiya, T. & Sugishita, M. Dichotic listening in patients with situs inversus: brain asymmetry and situs asymmetry. Neuropsychologia 37, 869–874 (1999).

    CAS  Article  PubMed  Google Scholar 

  132. 132

    Geschwind, N. & Galaburda, A. M. Cerebral Lateralization (MIT Press, 1987).

    Google Scholar 

  133. 133

    Lust, J. M. et al. Differential effects of prenatal testosterone on lateralization of handedness and language. Neuropsychology 25, 581–589 (2011).

    Article  PubMed  Google Scholar 

  134. 134

    Stein, J. L. et al. Identification of common variants associated with human hippocampal and intracranial volumes. Nature Genet. 44, 552–561 (2012).

    CAS  Article  PubMed  Google Scholar 

  135. 135

    Guadalupe, T. et al. Measurement and genetics of human subcortical and hippocampal asymmetries in large datasets. Hum. Brain Mapp. (2013).

  136. 136

    Button, K. S. et al. Power failure: why small sample size undermines the reliability of neuroscience. Nature Rev. Neurosci. 14, 365–376 (2013).

    CAS  Article  Google Scholar 

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S.E.F. and C.F. acknowledge support from the Max Planck Society.

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Correspondence to Roel M. Willems or Clyde Francks.

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The authors declare no competing financial interests.

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The ability to use both hands equally well. People of mixed handedness often do have hand preferences in individual tasks but no strong, overall bias across tasks.

Gene expression profiling

The measurement of mRNA expression of thousands of genes simultaneously using a quantitative technique.


An imprinted gene is a gene for which the copies that are inherited from father and mother are active to different degrees.

Laterality index

A quantitative index of left–right asymmetry. For handedness, this is typically based on questionnaires or tasks that assess degrees of hand preference or relative hand motor skill.

Lexical decision task

A task in which participants have to decide whether a string of letters forms an existing word or not. The speed with which participants make their decision is used as a measure for semantic memory of a word or of the strength of association between words.


Genetic effects that influence the development of multiple, distinct traits.


The ability to perform purposeful movements. These movements can be learned gestures or a pantomime of tool use.

Situs inversus

A condition in which the position of visceral organs is reversed compared with that in the majority of the population.

Split-brain patients

In split-brain patients, the corpus callosum (fibre bundles connecting the two hemispheres of the brain) is severely damaged or completely lesioned. This condition provides the possibility to study each hemisphere in isolation, providing insights into functional specialization of the hemispheres.

Tool-use pantomime task

A task in which participants are asked to mimic the hand movements that are related to tools presented on a screen. They execute the actions while holding an imaginary tool (for example, opening a bottle with a bottle opener).

Verb-generation task

A task in which participants are presented with a noun and have to generate verbs that go together with that noun (for example, for 'bread', responses could be 'eat' and 'slice').

Word-generation task

A task that is often used to study neural correlates of language production. In one form of this task, a letter is presented on the screen and the participant is asked to produce as many words starting with this letter as he or she can in a certain amount of time.

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Willems, R., der Haegen, L., Fisher, S. et al. On the other hand: including left-handers in cognitive neuroscience and neurogenetics. Nat Rev Neurosci 15, 193–201 (2014).

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