Using event-related potentials to identify user emotion caused by product color attribute

The accurate quantification of the correlation between product color attributes and user emotions is the key to product color emotional design (PCED). However, the traditional method of emotion quantification is subjective, one-sided, and contingent, which reduces the reliability of the research results. To this end, this paper proposes a method for PCED based on the quantification of electroencephalogram (EEG) physiological indicators. A medical product, namely an infant incubator, is used as the experimental stimulus samples, and “unsafe-safe” is used as the perceptual imager word pair to conduct EEG measurement experiments of the user's emotional state. Two types of data are obtained in the experiment, namely behavioral data and EEG data. Via the analysis of the two types of data, the EEG physiological characteristic indicators (the event-related potentials (ERPs) components) are obtained, which can explain the user’s emotional cognitive mechanism. Finally, the relationship between the user’s emotional state and EEG characteristics under the influence of product color attributes is explored. The conclusions are as follows. (1) The “safety” emotional value of the two-color samples is higher than that of the three-color samples, which indicates that the simpler the color matching, the higher the safety emotion attribute of the samples. (2) Via the study of the three attributes of hue, lightness, and chroma in the assistant colors of the two-color samples, it is found that when the hue attributes of the samples are red, cyan, and blue, the safety emotional value is higher; moreover, the higher the lightness attribute and the chroma attribute, the higher the safety emotion. Research on the two color attribute dimensions of hue harmony and color tone harmony between the auxiliary color of the three-color samples and the embellishment color revealed that the more consistent the hue harmony, the higher the safety emotion, and the more significant the difference in the color tone harmony, the higher the safety emotion. (3) The reaction time data in the behavioral data demonstrate that the participants had the longest average reaction time under neutral emotions. (4) The results of the time–frequency analysis of the EEG data reveal that there are apparent mid-to-early ERPs components between 100 and 300 ms after the appearance of the stimulus samples. The ERPs component analysis results show that the P1 component can reflect the emotional valence to a certain extent; the higher the amplitude of the P1 component, the more pronounced the negative emotions of the participants, and the lower the safety emotional evaluation value of the two-color samples, the higher the amplitude of the P1 component. Moreover, the N2 and P3 components can reflect the degree of emotional arousal to a certain extent, and the increase in their amplitude indicates the more substantial emotion of the participant; furthermore, the correlation between N2 and emotional arousal is higher. The two-color and three-color experiments revealed that the more neutral the emotional state, the lower the amplitudes of N2 and P3. This research is expected to provide a theoretical foundation and experimental data basis for PCED methods based on EEG physiological indicators.