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Exploratory activity was examined in 4 young baboons with the aim of investigating the type of spatial coding (purely geometric and/or by taking into account the identity of the object) used for the configuration of objects. Animals were individually tested in an outdoor enclosure for their exploratory reactions (contact time and order of spontaneous visits) to changes brought about to a configuration of different objects. Two kinds of spatial changes were made: a modification (1) of the shape of the configuration (by displacement of one object) and (2) of the spatial arrangement without changing the initial shape (exchanging the location of two objects). In the second experiment, the effect of a spatial modification of the global geometry constituted by four identical objects was investigated. Finally, in the third experiment, a substitution of a familiar object with a novel one was performed without changing the objects’ configuration. The baboons strongly reacted to geometrical modifications of the configuration. In contrast, they were less sensitive to modifications of local features that did not affect the initial spatial configuration. Analyses of spontaneous exploratory activities revealed two types of exploratory strategies (cyclic and back-and-forth). These data are discussed in relation to (1) the distinction between the encoding of geometric versus local spatial features and (2) the spatial function of exploratory activity. 相似文献
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First-grade males performed a 30-min visual vigilance task under 5 conditions of auditory background stimulation. The 5 conditions consisted of (1) continuous conversation, in which subjects listened to a tape of conversation spliced so that there were no intervals of silence lasting longer than 3 sec; (2) continuous reverse, in which subjects heard the continuous conversation tape played in reverse; (3) intermittent conversation, in which subjects heard alternating segments of conversation and silence; (4) intermittent reverse, in which subjects heard alternating segments of reverse conversation and silence; and (5) silence control. Compared with silence or continuous stimulation, intermittent stimulation produced better detection regardless of whether or not it was meaningful. High achievers made more correct detections than low achievers, but only in the second and third time periods. Few subjects made errors of commission. 相似文献
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