A Study Of Event-related Potentials Technique Applied On Clothing Emotion

The convenient channel of abundant information resources in modern society provideddiverse choices for consumers. The competition of clothing industry is intensified day by day.In addition to the translation of consumers needs and the development of the modern designphilosophy, it is very important to balance the functional and emotional needs of clothing,and convert the consumers' unconscious emotional states into specific design parameters, andto assist enterprise and personnel to design clothing which will satisfy the consumers'emotional needs and acceptances in order to gain brand recognition and market share in thepresent social environment. Therefore, it is necessary to analyze and study the consumers'emotional response toward clothing.The occurrence of emotion refers to the dual influences of mental mechanism andphysiological mechanism. Self-report based on mental mechanism is the expression ofsubjects' subjective attitudes, which has been used extensively in clothing evaluations.However, because of the restrictions of culture, social background and education level of thesubjects, and the changes of attitudes in the actual evaluation process, the stability andconsistency of data could not be guaranteed. In addition, subjects' understandings ofsensibility words and the deviations from self-emotional descriptions may lead to inaccurateresults. These errors include both system errors and random errors. Even though, theinfluence of errors could be reduced through reliability evaluations, it is difficult to eliminatethe influence of errors by a large margin. Therefore, even the psychological method ofemotional measurement is convenient and useful, it is lack of directness and accuracycompared with the emotional measurements through physiological index in specificcondition.Human brain, as the important organ of mental formation and cognitive function, itspotentials are closely related with psychological activities. Because the changes of humanbrain potentials are spontaneous and impulsive, the potentials are directly recorded from scalpto express process of mental activities. ERPs as a kind of evoked potential have thecharacteristics of high time resolution and constant waveform and lantency. Researchers canmeasure the real-time changes of potentials during stimuli occurrences (more focuses onoriginal emotional reactions), and produce continuous waveform of electrode potential inmulti-zones. By virtue of advanced computer technology and mathematical tools to processthe continuous and multi-regions waveforms, abundant information associated withpsychological activities could be obtained.Therefore, in order to explore an effective methodology to assess the consumer'semotional responses toward clothing, this research chose human emotions evoked by clothing as the research object, clearly proposed the concept of clothing emotion on the basis ofanalyzing emotional theory. Men's causal jacket was chosen as the research subject. On thebasis of design elements disassembly, a measured plane which contains three basic emotionswas constructed through data mining of the consumers' sensibility selections. This measuredplane was used as stimulus materials to research through the cognitive experiment ofemotional dimensions and the experiment of event-related potentials (ERPs) recordings. Theeffectiveness and relationship of the result from the two clothing emotion research methodswere compared and evaluated to construct an effective evaluation method of clothingemotional assessment based on the ERPs technology. The effectiveness of this method wasverified by the characteristics of extracted components and regions. It will aid to developmore accurate, convenient, efficient, and complete techniques for clothing emotion researchin the future. The whole study contained five parts.The first step was to clearly define the concept of clothing emotion from the consumer'semotional approval of both functional and emotional aspects of clothing; to study theemotion-generation mechanism psychologically and physiologically; and to analyze themeasuring methods of clothing emotion combined with emotional components. The resultscould be used as the theoretical references for the following study on clothing emotions.The second step was to get the major consumers emotional selections of the designelements from110effective questionnaires. Four design models were clustered usingK-means algorithm of data mining. According to the eigenvalue of each cluster, the typicaldesign model of each cluster was defined as the positive representation of that cluster.The neutral and the negative representations of each cluster were defined using the medianand the maximum Euclidean distances between the design models and eigenvalue in thatcluster accordingly. A measured plane was constructed that contained three basic emotions(positive, neutral and negative) and comprised12design samples totally. This plane was usedas the stimulus for dimensionality cognitive evaluation and ERPs recording in order to furtheranalyze and verify its effectiveness.The third step was to distinguish clothing emotion using dimension viewpoint, and todescribe the characteristics of emotional dimensions using cognitive tool.20subjects withdifferent professional background were invited to evaluate pleasure, arousal and dominanceof the constructed representative design samples using9-point scale. Emotional classificationfactors, the influence of gender factors and the relationship between three dimensions wereanalyzed using one-way analysis of variance, pared-samples T test, correlation analysis, et al.in SPSS. The statistic characteristics and significance of results were extracted and analyzed.According to the corresponding relations between level of pleasure and emotional categoriesin the measured plane, the accuracy of measured plane constructed by cluster algorithm andthe effectiveness of typical psychological measurement were evaluated separately. Forth, the samples in the constructed measurement plane were used as the stimulus, andsuperposed presented through E-Prime software. Real-time brain potentials of8subjects wererecorded through ERPs technique. The early, middle and late components in left, middle,right, frontal, and central, potential were off-line analyzed using peak-amplitude andpeak-latency measurement in SCAN. Potential changes (amplitude and latency) and reactiveregion related to different emotional categories were extracted and recognized using SPSS.The corresponding relations between the results and emotional categories in the originalmeasurement plane, the accuracy of the measurement plane constructed by cluster algorithmwere analyzed, and the effectiveness of physiological measurement were evaluated, in orderto provide physiological characteristic references for emotional assessment of clothing.Fifth?according to the research purpose, the conclusions were summarized through theanalysis of psychological experiment and physiological measurement. The innovations andvalues of this research were proposed. The advantages and limitations of this research and thedevelopment direction of ERPs technology used in emotional fashion design in the futurewere also discussed.The conclusions were as following:1. Different emotional categories constructed by clustering algorithm were significantlydifferent in the evaluation of emotional dimension. The results of dimensional cognition andemotional categories by clustered were consistent. It indicated the accuracy and effectivenessof the measurement plane constructed by cluster algorithm on one hand. On the other hand, italso proved the effectiveness of the SAM measurement used in clothing emotion researches.2. Clothing emotions evoked scalp recording related ERPs. Results indicated that theprocess of emotional visual information could be obtained by analyzing the amplitude andlatency (time) of ERPs components. By analyzing typical ERPs components, the main effectof amplitude and latency between emotional categories was overall significant, whichindicated the significant difference between the processing time and the intension of threeemotions. Therefore, different emotions evoked by clothing could be accurately recognizedby distinguishing the characteristics of potential components and regions. Especially, theearly component of ERPs was considered as one of the main reference indexes for clothingemotional recognition, the middle and late components were considered as the assistedreference indexes. These were applied to effectively evaluate the preferable level andconsuming intention of consumers to clothing design scheme.3. The emotional characteristics evoked by men' casual jackets were as following:(1) There was a positive correlation between pleasure and dominance, which indicatedthat higher pleasure was associated with stronger buying inclination. Therefore, valence couldbe used as the index to evaluate consumers' preferences.(2) The following component changes and response regions could be referred to when choosing brain potential characteristics as the index of emotional evaluation.Early ERPs components indicated that the processing time of negative stimulation wasshort, which indicated that the negative stimulation drew priority attention. Arousal levelbegan to influence waveform at110ms after stimulus onset. For the P1, negative stimuluselicited larger amplitude, the latency and amplitude in occipital region was significant.Therefore, the representation in occipital region was the largest of P1. Early components weresignificant in primary visual cortex which took charge for visual information.N2component was significantly changed in210-250ms after stimulus presented byanalyzing central and potential regions. The latency of negative stimulus was significantlyshortened, the amplitude was increased. Hemi-lateralization was not significant. There wasno difference between electrodes of P2. The amplitude of negative stimulus was larger thanpositive stimulus, potential region was significantly changed.Negative stimulus evoked the largest P3amplitude, and the largest latency. The meanamplitude of potential region was the largest. The processing intensity of right hemispherewas larger than the left hemisphere and the midline.The study and development of clothing emotion research using ERPs technology as thereference factors will improve and perfect the emotional fashion design system, and enhancethe design efficiency. It is significant in the application and development of Kansei design inthe emotional design field of clothing.