Kawabata H, Gyoba J, Inoue H, Ohtsubo H
Department of Psychology, Graduate School of Human-Environment Studies, Kyushu University, Fukuoka, Japan.
Perception. 2001;30(7):867-74. doi: 10.1068/p3213.
Four groups of eight 4-month-old infants were each habituated to one of four displays consisting of a grating of either low (0.4 cycle deg(-1) or high (1.2 cycles deg(-1) spatial frequency, whose central portion was covered up with a horizontal occluder which was either narrow (1.33 deg) or broad (4.17 deg). Posthabituation displays consisted of a complete grating of the same frequency as the habituated grating, along with a separate grating whose central portion was replaced with a black gap of the same height as the occluder in the habituation displays. All the infants, except those who were habituated to the high frequency with the broad occluder, looked longer at the separate grating than the complete grating display during posthabituation trials. Previously, we found that infants under 1 month of age perceive the grating continuation only when the occluder height is less than about 0.5 cycle of the grating; our present results show that this figure increases to about 1.6 cycles of the grating frequency in the case of 4-month-old infants. These findings indicate that those developmental changes depend on both the sufficiency of visual information available and the efficiency of the perceptual ability of infants for grasping spatial relationships.
四组八个4个月大的婴儿，每组都习惯了四种展示中的一种。这些展示由低（0.4周/度）或高（1.2周/度）空间频率的光栅组成，其中心部分被一个水平遮挡物遮住，该遮挡物要么窄（1.33度）要么宽（4.17度）。习惯化后的展示包括一个与习惯化光栅频率相同的完整光栅，以及一个单独的光栅，其中心部分被一个与习惯化展示中遮挡物高度相同的黑色间隙所取代。在习惯化后的测试中，除了那些习惯了宽遮挡物的高频光栅的婴儿外，所有婴儿看单独光栅的时间都比看完整光栅展示的时间长。此前，我们发现1个月以下的婴儿只有在遮挡物高度小于光栅约0.5个周期时才会感知到光栅的连续性；我们目前的结果表明，对于4个月大的婴儿来说，这个数字增加到了光栅频率的约1.6个周期。这些发现表明，这些发育变化既取决于可用视觉信息的充分性，也取决于婴儿把握空间关系的感知能力的效率。
