Saccadic localization of random dot targets
Saccadic localization of random dot targets
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DOI：
10.1016/s0042-6989(97)00232-0
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发表时间：
1998-03-01
期刊：
影响因子：
1.8
通讯作者：
Chubb, C
中科院分区：
文献类型：
--
作者：
McGowan, JW;Kowler, E;Chubb, C
在自然视觉场景中，扫视眼动的目标是空间延伸的物体，但扫视落在其中的单个位置。为了表征确定关注对象内的扫视目标位置的空间变换，我们研究了随机点的大图案的扫视定位，扫视以高精度落在图案的重心附近（平均误差< 10%;重心周围的SD =目标偏心率的7-11%）。通过使用加权重心来改进着陆位置的预测，其中分配给每个点的权重由于相邻点的存在而减小。根据点的偏心率或它们相对于图案边界的位置进行加权都没有效果。结果可以通过空间变换来解释，在空间变换中，由每个检测器的活动加权的初始检测器阵列的“局部符号”被平均以产生扫视目标。该模型可以解释大目标的准确和精确的扫视定位，同时保持对局部模式特征的敏感性。与识别模型不同，对象的边界与内部细节具有相同的地位。(C)1998爱思唯尔科技有限公司版权所有。
The targets for saccadic eye movements in natural visual scenes are spatially extended objects, yet saccades land at a single position within them. To characterize the spatial transformation that determines the saccadic goal position within attended objects, we studied saccadic localization of large patterns of random dots, Saccades landed with a high degree of precision near the center-of-gravity of the patterns (average error < 10%; SDs around the center-of-gravity = 7-11% of target eccentricity). Predictions of landing position were improved by using a weighted center-of-gravity, in which the weight assigned to each dot was reduced by the presence of neighboring dots. Weighting based either on the eccentricity of dots or their position relative to the boundary of the pattern had no effect. The results can be accounted for by a spatial transformation in which the "local signs" of an initial array of detectors, weighted by the activity of each, are averaged to yield the saccadic goal. This model can account for accurate and precise saccadic localization of large targets, while preserving sensitivity to local pattern characteristics. Unlike models of recognition, the boundary of the object has the same status as the internal details. (C) 1998 Elsevier Science Ltd. All rights reserved.