Department of Nursing Administration/Advanced Clinical Nursing, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Early Hum Dev. 2011 Jan;87(1):45-8. doi: 10.1016/j.earlhumdev.2010.09.371. Epub 2010 Oct 20.
Previous studies in adults have reported that handedness and gender can affect pain perception. However, it is currently unclear when these differences emerge in human development. Therefore, we examined prefrontal responses to pain stimulation among newborns during their first acute pain experience after birth.
Forty newborns at 4-6 days postnatal age were observed during clinically required blood sampling while prefrontal activation was measured with near infrared spectroscopy. Blood sampling in this study was the first experience of a procedure involving skin breaking for these infants. We divided subjects into a right-hand stimulation group (n=21) and a left-hand stimulation group (n=19), depending on whether blood was sampled from the right or the left hand. A three-way analysis of variance (ANOVA) was conducted to examine the effects of several variables on the magnitude of the oxy-Hb value in response to pain stimulus, including stimulus side (right hand or left hand), gender (male or female), recording side (right prefrontal area or left prefrontal area) and interactions between these variables.
The data revealed a significant effect of stimulus side (F (1, 72)=9.892, P=0.002), showing that the right-hand stimulation induced a greater prefrontal activation than the left-hand stimulation. No significant gender difference or interactions were found.
Our findings suggest that hand laterality affects pain perception even in neonates. However, gender differences in pain perception did not appear to occur during the neonatal period. Further investigations using brain-imaging techniques are required to identify laterality- or gender-related differences in pain processing in humans.
先前的成人研究报告称，利手和性别会影响疼痛感知。然而，目前尚不清楚这些差异在人类发育过程中何时出现。因此，我们检查了新生儿在出生后首次经历急性疼痛时前额对疼痛刺激的反应。
40 名 4-6 天大的新生儿在接受临床必需的采血时被观察到，同时使用近红外光谱测量前额叶激活情况。在这项研究中，对于这些婴儿来说，采血是第一次涉及皮肤破裂的程序。我们根据血液是从右手还是左手采集，将受试者分为右手刺激组（n=21）和左手刺激组（n=19）。采用三因素方差分析（ANOVA）来检验几种变量对疼痛刺激时 oxy-Hb 值幅度的影响，包括刺激侧（右手或左手）、性别（男或女）、记录侧（右前额区或左前额区）以及这些变量之间的相互作用。
数据显示刺激侧的影响具有统计学意义（F (1, 72)=9.892, P=0.002），表明右手刺激比左手刺激引起更大的前额叶激活。未发现性别差异或相互作用。
我们的研究结果表明，即使在新生儿中，手的利手性也会影响疼痛感知。然而，在新生儿期似乎没有出现疼痛感知的性别差异。需要使用脑成像技术进行进一步研究，以确定人类疼痛处理中与侧化或性别相关的差异。
