Verbal Interference Causes Categorization Impairments：Impaired Taxonomic Categorization And Preserved Thematic Categorization

The basic function of the language is communication, besides the basic function,language also plays a certain role in the field of thought and cognition, which meansextracommunicative function of language. People can classify objects by differentdimensions. In this kind of ability, do language plays a role? This study uses theverbal interference methods to study the influence of the language to the classificationprocess. In this study, we make the normal adults in verbal interference to do someclassifying task, we want to know whether normal adults in verbal interferencesituation can show the selective categorization impairments. Some current researchindicates that the adults can according to different needs or standard to classify theitems, and this kind of ability in aphasia patients has been affected, so can normaladult participants in verbal interference situation show the same pattern to aphasiapatients, which is the question in this study.This study use112subjects to study whether verbal interference affects theodd-one-out task, and the difference in different type of criterion. There threeexperiments in this study according to the three different interference:Experiment1uses38subjects randomly allocation to picture group(n=19) andword group(n=19). The experiment of Picture group use2conditions (control, verbalinterference)×3blocks (size, color, theme). The verbal interference is by the numberrehearsing to finishing. The Word group is as same as the Picture goup, only use wordstimulus instead of picture stimulus. The result of experiment shows that thenumerical verbal interference remarkably affects the taxonomiccategorization(color/size) which needs the independent perceptual dimensions, but notaffects the thematic categorization, which uses the whole relations of objects. Theword group shows the same pattern with the picture group.Experiment2uses36subjects randomly allocation to picture group(n=18) andword group(n=18). The experiment of Picture group use2conditions (control, verbalinterference)×3blocks (size, color, theme). The verbal interference is by thesentencer rehearsing to finishing. The Word group is as same as the Picture goup, only use word stimulus instead of picture stimulus. The result of experiment shows that theexperiment2show the same pattern with the experiment1, the sentence verbalinterference remarkably affects the taxonomic categorization(color/size), but notaffects the thematic categorization. The word group shows the same pattern with thepictrue group.Experiment3is a contrast experiment with experiment1and2. Visuospatialinterference replaced verbal interference in Experiment3to demonstrate wether thecategorization impairments is only in verbal interference. The result of experiment3shows that the visuospatial interference does not affect both taxonomic categorizationand thematic categorization.The result of this study shows that the categorization impairments in experiment1and2is peculiar to the verbal interference, and is not any other interference couldcause. This means that language plays an very important role in the ability ofcategorization, and also supports the point of extracommunicative function oflanguage.