然后是相关的英文资料:
Were the Victorians cleverer than us? The decline in general intelligence estimated from a meta-analysis of the slowing of simple reaction time
(http://www.sciencedirect.com/science/article/pii/S0160289613000470)
The Decline of the Average Human I.Q.
(http://uhaweb.hartford.edu/BRBAKER/)