基于位置和基于语义交互作用的无意识启动

The Interaction between Location-based and Semantics-based Unconscious Priming Effects

采用线索-靶子范式,同时操纵刺激的位置和语义属性,考察了基于位置和基于语义交互作用的无意识启动。实验1和实验2分别要求被试完成定位任务和辨别任务。结果发现,当刺激的位置属性与实验任务需求相关时,无论刺激的语义属性是否一致都产生了基于位置的启动效应;当刺激的语义属性与实验任务相关时,出现了基于位置和基于语义交互的无意识启动,即启动项和目标项的位置不同时,语义辨别任务存在启动效应;而启动项与目标项位置相同时,语义辨别任务存在着抑制趋势。研究结果表明,基于位置和基于语义交互作用的无意识启动效应仅存在于辨别任务中,而不存在于定位任务中。

Priming is an implicit memory effect in which exposure to a stimulus influences a response to a later stimulus. It can occurfollowing repetition of a perceptual, semantic, or conceptual stimulus, even in an unconscious way. Previous studies found that uncon-scious information can not only get itself a greater degree of processing, but also evoke attention for its position in space, which pro-duced location - based priming effect. Studies have also found that unconscious information is not only able to get the low - level charac-teristics processing, but also get the high - level semantics processing. So far, almost all previous studies focused on the different attrib-utes of stimuli in unconscious information processing separately, such as location, size, shape, and semantics. But in order to directlyexamine whether they have the same underlying mechanisms and how they possibly interact in contributing to attentional or response bi-as, we needed to use the cue - target paradigm and co - vary the spatial location and semantic properties of stimuli simultaneously. Weaimed at investigating the interaction between location -based and semantics -based unconscious priming effects. The two experiments used essentially the same design and stimuli, with two within - subjects factors designating the relations be-tween the cue and the target. The first factor was whether the cue was ipsilateral or contralateral to the target （ i. e. , cue - target loca-tion correspondence or cue validity） and the second factor was whether semantic consistency of the cue was the same as or different fromthe semantic consistency of the target. The cue and the target were four digits, 3,4, 6 and 7. In some trials the prime was congruentwith the target （ both numbers fell on the same side of 5）, and in other trials it was incongruent （ one number being larger than 5, andthe other being smaller; Fig. 1 ）. In Experiment 1, subjects were required to press a response key with one finger if the target was onthe left side, with the other finger if the target was on the right side. In Experiment 2, we asked subjects to perform a simple semanticcategorization task on the target numeral. Subjects were asked to press a response key with one finger if the target was larger than 5, andwith the other finger if the target was smaller than 5. The presentation of the cue and the target on the ipsilateral and contralateral sidesand the combination of the same or different frequencies as cues and targets were completely balanced. We found that there were priming effects based on the location, when the location attributes of stimuli were associated with the ex-perimental task demands, regardless of whether the semantic properties of stimuli were identical. However, when the semantic proper-ties of stimuli were associated with the experimental task demands, there was an interaction between location - based and semantics -based unconscious priming effects, i.e. , when priming items were different than the position of the target items, there were semanticpriming effects in the semantic discrimination task ; while priming items were the same as the location of target items, there was an in-hibitory tendency in the semantic discrimination task. These results suggested that the interaction between location -based and seman-tics - based unconscious priming effects only appeared in the discrimination task, but not in the location task.