Tassinari G, Aglioti S, Chelazzi L, Marzi C A, Berlucchi G
Neuropsychologia. 1987;25(1A):55-71. doi: 10.1016/0028-3932(87)90043-1.
By using a simple reaction time (RT) paradigm we have investigated the spatial distribution of the benefits and costs of voluntarily directed attention and of the inhibitory after-effects of covert orienting. In the first experiment subjects deliberately allocated attention to each one of five stimulus positions disposed along the horizontal meridian, while at the same time fixing their eyes on the central position. The separation in visual angle between the central position and the two nearest positions, one on the left and the other on the right, was 10 degrees; that between the central position and the two most eccentric positions was 30 degrees. By comparing RT to brief flashes of light presented at each position during directed attention with RT to identical flashes at the same position during diffuse attention (i.e. in a condition in which subjects paid equal attention to all five positions), it was possible to determine that benefits, that is RT decreases relative to the diffuse-attention condition, were strictly limited to the attended position. Costs, i.e. RT increases relative to the diffuse-attention condition, showed a more diffuse and complex spatial pattern. When attention was directed to one of the noncentral positions, costs were apparent at the two contralateral positions and at the central position, but not at the ipsilateral position. When attention was directed to the central position, costs occurred at all other positions. This suggests a special role for the vertical meridian in delimiting the area of costs when one covertly orients towards the opposite right or left visual half field. Work of others and our preliminary evidence indicate that the area of costs is similarly limited by the horizontal meridian when one orients toward the opposite upper or lower visual field. In the second experiment we studied the inhibitory after-effect of covert orienting. Orienting to a light stimulus without moving the eyes to it may induce a short-lived facilitation of the speed of response to a second stimulus presented at the same position, but this facilitation is followed by a profound and prolonged RT retardation. By using a two-flashes paradigm we observed this RT retardation not only when the two stimuli appeared at the same position, but also when they occurred at different locations in the same altitudinal or lateral visual hemifield. There were no inhibitory after-effects when the two stimuli appeared on opposite sides of the vertical or horizontal meridian.(ABSTRACT TRUNCATED AT 400 WORDS)
通过使用一种简单的反应时（RT）范式，我们研究了自愿定向注意的益处和代价的空间分布，以及隐蔽定向的抑制后效。在第一个实验中，受试者将注意力有意地分配到沿水平子午线排列的五个刺激位置中的每一个，同时将眼睛固定在中央位置。中央位置与左右两侧最近的两个位置之间的视角间隔为10度；中央位置与两个最偏心位置之间的视角间隔为30度。通过比较在定向注意期间每个位置呈现的短暂闪光的反应时与在分散注意期间（即受试者对所有五个位置给予同等注意的条件下）相同位置的相同闪光的反应时，可以确定益处，即相对于分散注意条件下反应时的减少，严格限于被注意的位置。代价，即相对于分散注意条件下反应时的增加，呈现出更分散和复杂的空间模式。当注意力指向非中央位置之一时，代价在两个对侧位置和中央位置明显，但在同侧位置不明显。当注意力指向中央位置时，代价出现在所有其他位置。这表明当一个人向右侧或左侧视觉半视野的对侧进行隐蔽定向时，垂直子午线在界定代价区域方面具有特殊作用。其他人的研究工作和我们的初步证据表明，当一个人向上或下视觉半视野的对侧定向时，代价区域同样受到水平子午线的限制。在第二个实验中，我们研究了隐蔽定向的抑制后效。在不将眼睛移向光刺激的情况下对其进行定向可能会导致对在同一位置呈现的第二个刺激的反应速度出现短暂的促进，但这种促进之后会出现深刻而持久的反应时延迟。通过使用双闪光范式，我们不仅在两个刺激出现在同一位置时观察到了这种反应时延迟，而且当它们出现在同一高度或横向视觉半视野的不同位置时也观察到了。当两个刺激出现在垂直或水平子午线的两侧时，没有抑制后效。（摘要截于400字）
