Facial Expressions Of The Effect Of Pre-search

The Preview Seareh Paradigm is an important method of Priority selection mechanism in the visual search, since it was created by Watson and Humphreys,in 1997. The experiment had three conditions,single-feature search condition,form-color conjunction search condition and preview condition.In the preview condition, firstly,present a set of distractors,after 1000ms,present another some distractors and a target again.In the form-color conjunction search condition,present distractors and target in the same time,asked the participants to complete the search task.The results of the experiment found that the performance in preview condition was better than that in form-color conjunction search condition,almost the same with the performance in single-feature search condition.that is previewing a set of distractors allows them to be ignored in a subsequent visual search task,this is called preview effect.The preview effect receives many factors the influencesjncluding time interval,the change of old items and so on.Facial expression is an important non-verbal stimuli, is both biological and social significance of the visual stimulus, contains a wealth of information.Facial expressions of human existence and social interaction adaptation has important implications.Previous studies, mainly,regarded letters or numbers that we are so familiar, as experimenttal materials. In this study,we use emotional faces as the experimental materials,in order to examine the preview effect can be obtained with emotional faces,as well as,to further explore its preview effect mechanism.The study is adopted standard preview search paradigm,divided into three experiments:Experiment 1 adopted the standard preview search paradigm and 3×3×2 experimental design,asked the participants to complete the search task for positively or negatively valenced schematic face targets among neutral face distractors,so as to examine the preview benefit with neutral previewed faces.Experiment 2 which used a similar experimental paradigm as experimment 1, asked the participants to complete the search task for neutral or negatively valenced schematic face targets among positively face distractors,so as to determined whether positively valenced faces can also be effectively ignored.Experiment 3 using the same paradigm as experiment 2, asked the participants to complete the search task for neutral or positively valenced schematic face targets among negatively face distractors,so as to examined the efficiency of ignoring negatively valenced faces. Given the previously demonstrated ability of negative faces to attract and hold attention,we might expect that it would be particularly difficult to ignore them during time-based visual search tasks, leading to a greatly reduced or abolished preview benefit.Integrated three experiments results and relevant discussions, this study got the following several conclusions:(1) From three experiments results, the speed of preview search is slower than the half-set baseline,bue also fast than the full-set baseline,ranging between the two experiment conditions.it can be obtained,a robust but not full preview benefit was obtained when ignoring face stimuli.(2) These types of stimuli are known to produce a negative valence advantage in standard visual search tasks,from the results of three experiments of this study,a negative target face search advantage remained during timebased selection conditions.(3) Compared with experiment 2 and experiment 3, the large preview benefit in the experiment 2 than in the experiment 3, Therefore, Ignoring negative faces took longer than ignoring positive faces.