Sex differences in handedness, asymmetry of the Planum Temporale and functional language lateralization

@article{citeulike:3036490, abstract = {Many studies have investigated sex differences in language lateralization. Despite the large number of investigations, controversy about the presence of sex differences in lateralization remains. This study aims to provide a complete overview of sex differences in several reflections of language lateralization: handedness, asymmetry of the Planum Temporale (PT) and functional lateralization of language, measured by asymmetric performance on dichotic listening tests (Right Ear Advantage) and asymmetry of language activation asmeasured with functional imaging techniques. Meta-analysis of studies that assessed handedness in males and females yieldedmore left-handedness inmales (mean weighted odds ratio: 1.25, pb0.001). Meta-analysis of studies on PT asymmetry yielded no sex difference (Hedges g=−0.11, p=0.68). Results of the meta-analysis on dichotic listening studies also retrieved no sex difference in lateralization (Hedges g=0.09, p=0.18). When the studies were subdivided according to the paradigm they applied, studies that used the consonant–vowel task yielded a sex difference favouring males, while studies that applied other paradigms yielded no sex difference. The subdivision into applied paradigm largely overlapped with the subdivision into studies that did or did not focus on sex differences as their main topic. The observed sex effect may therefore be caused by publication bias. Meta-analysis of functional imaging studies yielded no sex difference (Hedges g=0.01, p=0.73) in language lateralization. Sub-analyses of studies that applied different paradigms all yielded no sex difference. In conclusion, males are more frequently non-right handed than females, but there is no sex difference in asymmetries of the Planum Temporale, dichotic listening or functional imaging findings during language tasks. {\copyright} 2008 Elsevier B.V. All rights reserved.}, author = {Sommer, Iris E. and Alemanc, Andr\'{e} and Somers, Metten and Boks, Marco P. and Kahn, Ren\'{e} S. }, citeulike-article-id = {3036490}, journal = {Brain Research}, keywords = {asymmetry, difference, functional, handedness, language, lateralization, meta-analysis, neuroimaging, neuroscience, sex}, pages = {76--88}, posted-at = {2008-07-23 10:28:38}, priority = {2}, title = {Sex differences in handedness, asymmetry of the Planum Temporale and functional language lateralization}, volume = {1206}, year = {2008} }

TY - JOUR ID - citeulike:3036490 L3 - citeulike-article-id:3036490 TI - Sex differences in handedness, asymmetry of the Planum Temporale and functional language lateralization JF - Brain Research VL - 1206 SP - 76 EP - 88 N2 - Many studies have investigated sex differences in language lateralization. Despite the large number of investigations, controversy about the presence of sex differences in lateralization remains. This study aims to provide a complete overview of sex differences in several reflections of language lateralization: handedness, asymmetry of the Planum Temporale (PT) and functional lateralization of language, measured by asymmetric performance on dichotic listening tests (Right Ear Advantage) and asymmetry of language activation asmeasured with functional imaging techniques. Meta-analysis of studies that assessed handedness in males and females yieldedmore left-handedness inmales (mean weighted odds ratio: 1.25, pb0.001). Meta-analysis of studies on PT asymmetry yielded no sex difference (Hedges g=−0.11, p=0.68). Results of the meta-analysis on dichotic listening studies also retrieved no sex difference in lateralization (Hedges g=0.09, p=0.18). When the studies were subdivided according to the paradigm they applied, studies that used the consonant–vowel task yielded a sex difference favouring males, while studies that applied other paradigms yielded no sex difference. The subdivision into applied paradigm largely overlapped with the subdivision into studies that did or did not focus on sex differences as their main topic. The observed sex effect may therefore be caused by publication bias. Meta-analysis of functional imaging studies yielded no sex difference (Hedges g=0.01, p=0.73) in language lateralization. Sub-analyses of studies that applied different paradigms all yielded no sex difference. In conclusion, males are more frequently non-right handed than females, but there is no sex difference in asymmetries of the Planum Temporale, dichotic listening or functional imaging findings during language tasks. © 2008 Elsevier B.V. All rights reserved. KW - asymmetry KW - difference KW - functional KW - handedness KW - language KW - lateralization KW - meta-analysis KW - neuroimaging KW - neuroscience KW - sex AU - Sommer, Iris AU - Alemanc, André AU - Somers, Metten AU - Boks, Marco AU - Kahn, René PY - 2008/// ER -