Trick Lana M
Department of Psychology, University of Guelph, Guelph, Ontario, Canada.
Percept Psychophys. 2008 Jul;70(5):743-60. doi: 10.3758/pp.70.5.743.
This study investigates the effects of item heterogeneity (differences in color and shape) and moment-to-moment feature change as it relates to the issue of whether subitizing and counting involve different processes. Participants enumerated displays of up to eight items that were either homogeneous or heterogeneous. In situations where the heterogeneous displays always had approximately half of the items of one type and half of the other, heterogeneity significantly sped enumeration in the counting range (6-8 items) and significantly slowed enumeration in the subitizing range (1-3 items), a dissociation that suggests that subitizing and counting involve different operations. Moment-to-moment feature change had no effect on subitizing. However, feature change slowed counting, but only when participants were enumerating heterogeneous items that were half of one type and half of the other, as might be expected if participants were using differences in features to select items by type.
本研究调查了项目异质性（颜色和形状的差异）以及瞬间特征变化与即时数数和计数是否涉及不同过程这一问题的关系。参与者对多达八个同质或异质的项目展示进行计数。在异质展示中，一种类型的项目和另一种类型的项目总是各占大约一半的情况下，异质性在计数范围内（6 - 8个项目）显著加快了计数速度，而在即时数数范围内（1 - 3个项目）显著减慢了计数速度，这种分离表明即时数数和计数涉及不同的操作。瞬间特征变化对即时数数没有影响。然而，特征变化减慢了计数速度，但只有当参与者在计数一半是一种类型、一半是另一种类型的异质项目时才会如此，这正如预期的那样，如果参与者是利用特征差异按类型选择项目的话。
