Avant L L, O'Boyle M W, Thieman A A, Tepin M B, Smith F R
Department of Psychology, Iowa State University, Ames 50011-3182.
Brain Cogn. 1993 May;22(1):63-84. doi: 10.1006/brcg.1993.1025.
Two experiments tested perceptual processing of Garner and Clement's (1963) good and poor five-dot patterns by the left and right hemispheres. Two (good) patterns were from four-member equivalence sets, and the other (poor) pattern was from an eight-member equivalence set. One of the good patterns formed a T shape that could be processed as a linguistic unit. In Experiment 1, 80 right-handed subjects made same-different judgments for lateralized 200-msec paired presentations of these patterns. When both presentations were to the RVF/LH, response latency was faster for the T pattern than for the other two. When both presentations were to the LVF/RH, response latency was faster for the two good patterns than for the poor pattern. When the first pattern was presented to the RVF/LH and the second was presented to the LVF/RH, response latencies were lower for the two good patterns than for the poor pattern. Also, when the first pattern was presented to the LVF/RH and the second was presented to the RVF/LH, response latency was faster for the T pattern than for the other good pattern which was, in turn, faster than for the poor pattern. Experiment 2 used a duration judgment task (Avant & Lyman, 1975) to test effects of pattern goodness on apparent durations of pre- and postmasked 10-msec pattern presentations. With left hemisphere inputs, presentations of good patterns were judged to be longer than presentations of the poor pattern. When each hemisphere compared the T and the other good pattern, presentations of the T pattern were judged to be longer, and the right hemisphere further discriminated among pattern orientations. Presentations of the T pattern to each hemisphere were judged to be longer than presentations of the poor pattern, and both hemispheres discriminated among orientations of both patterns. These results indicate that the two hemispheres can, during perceptual processing, function cooperatively, and that both prerecognition and conscious perceptual operations are guided by task demands.
两项实验测试了左右半球对加纳和克莱门特（1963）提出的优质和劣质五点图案的感知处理。两种（优质）图案来自四成员等价集，另一种（劣质）图案来自八成员等价集。其中一种优质图案形成了一个可作为语言单元处理的T形。在实验1中，80名右利手受试者对这些图案进行200毫秒的侧向配对呈现做出相同-不同判断。当两个呈现都在右视野/左半球时，T形图案的反应潜伏期比其他两种图案更快。当两个呈现都在左视野/右半球时，两种优质图案的反应潜伏期比劣质图案更快。当第一个图案呈现给右视野/左半球，第二个图案呈现给左视野/右半球时，两种优质图案的反应潜伏期比劣质图案更低。此外，当第一个图案呈现给左视野/右半球，第二个图案呈现给右视野/左半球时，T形图案的反应潜伏期比另一种优质图案更快，而另一种优质图案又比劣质图案更快。实验2使用持续时间判断任务（阿万特和莱曼，1975）来测试图案优劣对前后掩蔽的10毫秒图案呈现的表观持续时间的影响。对于左半球输入，优质图案的呈现被判断为比劣质图案的呈现更长。当每个半球比较T形图案和另一种优质图案时，T形图案的呈现被判断为更长，并且右半球进一步区分图案方向。T形图案呈现给每个半球时被判断为比劣质图案的呈现更长，并且两个半球都区分了两种图案的方向。这些结果表明，在感知处理过程中，两个半球可以协同发挥作用，并且预识别和有意识的感知操作都受任务需求的引导。
