title: Intelligence and handedness: Meta-analyses of studies on intellectually disabled, typically developing, and gifted individuals.
abstract: Understanding the relationship between cerebral laterality and intelligence is important in elucidating the neurological underpinnings of individual differences in cognitive abilities. A widely used, behavioral indicator for cerebral laterality, mainly of language, is handedness. A number of studies have compared cognitive abilities between groups of left- and right-handers, while others have investigated the handedness prevalence between groups of different cognitive abilities. The present study comprises five meta-analyses of studies that have assessed the handedness prevalence in (a) individuals with intellectual disability (ID) of unknown/idiopathic nature compared to typically developing (TD) individuals, and (b) individuals with intellectual giftedness (IG) compared to TD individuals. Nineteen data sets totaling 16,076 participants (5795 ID, 8312 TD, and 1969 IG) were included in the analyses. Elevated levels of atypical handedness were found to be robust only for the ID to TD comparison. Findings constrain the range of acceptable theories on the handedness distribution for different intelligence levels.
authors.affiliation: Research Centre for Psychophysiology and Education, School of Education, National and Kapodistrian University of Athens, 27 Deinokratous Str, 106 75 Athens, Greece; Cognition and Health Research Group, Medical Sciences Division, Department of Experimental Psychology, University of Oxford, Tinbergen Building, 9 South Parks Road, Oxford OX1 3UD, UK. Electronic address: marietta.papadatou-pastou@seh.oxon.org.
authors.forename: Marietta
authors.initials: M
authors.lastname: Papadatou-Pastou
authors.affiliation: Research Centre for Psychophysiology and Education, School of Education, National and Kapodistrian University of Athens, 27 Deinokratous Str, 106 75 Athens, Greece. Electronic address: dmtomprou@primedu.uoa.gr.
authors.forename: Dimitra-Maria
authors.initials: DM
authors.lastname: Tomprou
mesh_terms: D002648:Child; D002657:Child Development / Q000502:physiology*; D002672:Child, Gifted; D007839:Functional Laterality; D006801:Humans; D008607:Intellectual Disability; D015201:Meta-Analysis as Topic
keywords: Behavioral laterality; Hand preference; IQ; Intellectual disability; Intellectual giftedness; Language laterality