Bull Rebecca, Benson Philip J
School of Psychology, William Guild Building, University of Aberdeen, Aberdeen AB24 2UB, Scotland, UK.
Horm Behav. 2006 Aug;50(2):194-9. doi: 10.1016/j.yhbeh.2006.02.008. Epub 2006 Apr 3.
Digit ratio (as a putative indicator of prenatal androgen exposure) is related to a range of sexually dimorphic abilities, including spatial skills and mathematical ability. This study examined a phenomenon known as the SNARC effect (Spatial Numerical Association of Response Codes), which is taken as evidence of a mental representation of magnitude along a left-right-oriented number line, with low magnitudes associated with the left side of space, and high numbers with the right side of space. Participants made a parity judgement of numbers with responses made with a left key to odd numbers and a right key to even numbers. This was reversed for a second block of trials. Response times to numbers one to nine with both the right and left hand were calculated, and regression analyses conducted to analyse whether lower magnitudes were responded to faster with the left hand and higher magnitudes with the right hand. Participants with lower (more masculine) digit ratios on the right hand showed a stronger SNARC effect compared to participants with high digit ratios. This pattern of results was also found when the analyses were conducted separately for men and women. Results from left hand digit ratios indicated that only low digit ratio females showed a significant SNARC effect. These findings add to a growing literature on the relationship between digit ratio and cognitive abilities; in this case, simple cognitive representations that are accessed automatically rather than complex skills such as mental rotation or "mathematics" where a variety of solution strategies may be utilised.
指长比（作为产前雄激素暴露的一种假定指标）与一系列性别差异能力有关，包括空间技能和数学能力。本研究考察了一种被称为SNARC效应（数字反应码的空间数字关联）的现象，该效应被视为沿左右方向数字线对数量进行心理表征的证据，即较小的数量与空间左侧相关联，而较大的数字与空间右侧相关联。参与者对数字进行奇偶判断，用左键对奇数做出反应，用右键对偶数做出反应。在第二组试验中，这种情况则相反。计算了用右手和左手对1到9的数字的反应时间，并进行了回归分析，以分析左手对较小数量的反应是否更快，右手对较大数量的反应是否更快。右手指长比更低（更具男性特征）的参与者比指长比高的参与者表现出更强的SNARC效应。当分别对男性和女性进行分析时，也发现了这种结果模式。左手指长比的结果表明，只有低指长比的女性表现出显著的SNARC效应。这些发现为关于指长比与认知能力之间关系的不断增长的文献增添了内容；在这种情况下，是自动获取的简单认知表征，而不是诸如心理旋转或“数学”等复杂技能，后者可能会采用多种解决策略。
