Smythe Pamela, Annett Marian
School of Psychology, University of Leicester, University Road, Leicester LE1 7RH, UK.
J Child Psychol Psychiatry. 2006 Feb;47(2):205-12. doi: 10.1111/j.1469-7610.2005.01463.x.
The right shift (RS) theory of handedness suggests that poor phonology may occur in the general population as a risk associated with absence of an agent of left cerebral speech, the hypothesised RS + gene. The theory predicts that poor phonology is associated with reduced bias to right-handedness.
A representative cohort of primary school children was assessed on tests of phonology, nonverbal ability, literacy, and handedness. There were three types of analysis; for discrete variables, poor phonology and left hand preference; for continuous variables, phonology factor scores and hand skill; for "cases" of specifically poor phonology.
Reduced bias to dextrality was found in those with poor phonology for all types of analysis. Trends were similar for both sexes but stronger in males than females. Poor phonology was associated with a raised proportion of left-handed brothers. There was a strong association between poor phonology and poor literacy, but not all those with specifically poor phonology were poor readers or spellers. Among children with poor phonology but not poor for other variables, some 23-31% were left-handed writers.
Poor phonological processing is associated with reduced bias to the right hand, consistent with absence of an agent of left hemisphere advantage.
利手的右移（RS）理论表明，在普通人群中可能会出现语音能力差的情况，这是一种与假定的RS +基因缺失相关的风险，该基因是左脑语言功能的一个因素。该理论预测，语音能力差与右利手倾向降低有关。
对一组具有代表性的小学生进行了语音、非语言能力、读写能力和利手测试。有三种类型的分析：对于离散变量，即语音能力差和左手偏好；对于连续变量，即语音因子得分和手部技能；对于语音能力特别差的“案例”。
在所有类型的分析中，语音能力差的人右利手倾向降低。男女趋势相似，但男性比女性更明显。语音能力差与左利手兄弟的比例增加有关。语音能力差与读写能力差之间存在很强的关联，但并非所有语音能力特别差的人都是阅读或拼写能力差的人。在语音能力差但其他变量不差的儿童中，约23 - 31%是左利手书写者。
语音处理能力差与右利手倾向降低有关，这与左半球优势因素缺失一致。
