Sieratzki Jechil S, Woll Bencie
Human Communication Science, University College, London, United Kingdom.
Epidemiol Psichiatr Soc. 2002 Jul-Sep;11(3):170-6. doi: 10.1017/s1121189x00005686.
To assess competing explanations for the universal preference of mothers to cradle infants on their left side and to propose a relation to hemispheric asymmetry for social attachment and communication behaviour.
A review of observational, experimental, physiological, psychological, neuro-physiological, and neuro-psychological studies, including new findings on the cradling behaviour of mothers with auditory or visual impairments.
A significant left-cradling bias is observed in both right- and left-handed mothers which cannot adequately be explained by arguments based on handedness or closer contact to the soothing sound of the maternal heartbeat. Observations of primate behaviour have led to the suggestion that the left-cradling bias may be related to a left visual field (right hemisphere) advantage for monitoring an infant's facial expressions of distress. However, more than just monitoring, cradling subserves the mother's connection with the infant. For that reason, we have suggested that left cradling might be related to a right hemisphere specialisation for emotional communication, i.e. the speech melody, smiles, signals, and stroking which mothers use to interact with their infants. Studies of mother-infant interaction show that the sound of the mother's voice is more soothing when cradling on the left, more stimulating when cradling on the right. Cradling laterality may thus be related to emotional state and behavioural intent. There is also evidence to suggest that left cradling is linked to a special role of the right hemisphere in social attachment behaviour. This function may be disturbed in mothers with post-natal depression who show abnormal right hemisphere activity.
Cradling embodies the symbiotic relationship between mother and infant; various lines of evidence support the suggestion that the universal preference of mothers to cradle infants on their left side is related to a right hemisphere dominance for social attachment and communication behaviour.
评估关于母亲普遍倾向于用左侧怀抱婴儿的各种解释，并提出其与社会依恋和交流行为的半球不对称性之间的关系。
对观察性、实验性、生理学、心理学、神经生理学和神经心理学研究进行综述，包括对有听觉或视觉障碍母亲怀抱行为的新发现。
右利手和左利手母亲均表现出明显的左侧怀抱偏好，基于利手或更靠近母亲心跳舒缓声音的观点无法充分解释这一现象。对灵长类动物行为的观察表明，左侧怀抱偏好可能与左视野（右半球）在监测婴儿痛苦面部表情方面的优势有关。然而，怀抱婴儿不仅仅是监测，它还促进了母亲与婴儿的联系。因此，我们认为左侧怀抱可能与右半球在情感交流方面的特化有关，即母亲与婴儿互动时使用的语音旋律、微笑、信号和抚摸。母婴互动研究表明，左侧怀抱时母亲的声音更舒缓，右侧怀抱时更具刺激性。怀抱的偏向性可能因此与情绪状态和行为意图有关。也有证据表明左侧怀抱与右半球在社会依恋行为中的特殊作用有关。产后抑郁症母亲的右半球活动异常，这一功能可能受到干扰。
怀抱体现了母婴之间的共生关系；各种证据支持这样的观点，即母亲普遍倾向于用左侧怀抱婴儿与右半球在社会依恋和交流行为中的主导地位有关。
