Neuronal??Activity during Purchase Decision Making Process Revealed Using??Electroencephalography (EEG)

????????? ?????? ?????? ????????? ????????? ????????? ????????? ??? ????????? ???????????????. ???????????? ?????? ????????? ?????? ????????? ????????? ?????? ????????? ?????? ?????? ?????? ????????? ?????? ????????? ?????? ?????? ?????? ???????????? ????????? ?????? ?????? ????????? ????????? ??????. ??????, ????????? ????????? ?????? ??? ????????? ????????? ????????? ????????? ???????????? ??????????????? ?????? ????????? ????????? ?????? ??????????????? ????????? ???????????? ?????? ???????????? ???????????? ????????? ???????????? ?????? ???????????? ????????? ?????? ????????? ??????. ????????? ??? ????????? ?????????????????? ????????? ????????? ???????????? ???????????? ??????????????? ????????? ?????? ????????? ????????? ????????? ??????????????? ??????????????? ??????. ????????? ???????????? ?????? ????????? ?????? ????????? ????????? ????????? ?????? ????????? ????????? ??????, ????????? ?????? ????????? ?????? ???????????? ????????? ???????????? ????????? ???????????? ????????? ???????????? ???????????? ????????? ??????????????? ???????????? ??????????????? ?????????????????? ????????? ??????????????? ????????? ???????????? ?????? ???????????? ??????????????? ????????? ???????????? ??????. ????????? ?????? ?????? ???????????? ????????? ???????????? ????????? ????????? ????????? neuroimaging ????????? ??????????????? ?????? ???????????? ??????. ??? ??????????????? ???????????? ?????? ?????? ?????? ????????? ???????????? ????????? ????????? ????????? ????????? ?????? ?????? ?????? ??????????????? ??? ????????? ?????? ????????? ???????????????. ??? ?????? ??????????????? ?????? ?????? ???????????? ???????????? ?????? ????????? ?????? ?????? ??? ????????? ??????????????????. ?????? ?????? ??????????????? ??????, ????????? ???????????? ????????? ??????, ?????? ????????? ????????? ????????? ????????? ?????? ???????????? ?????? ????????? ???????????? ?????????. ????????? ?????? ?????????????????? ??????????????? ????????? ??????????????? ?????????????????? ???????????? ???????????? ??? ???????????? ????????? ????????? ?????? ????????? ?????? ?????? ????????? ?????? ????????? ??????????????? ???????????? ??? ???????????? ??? ????????? ????????? ????????? ??? ???????????? ??? ?????? ????????? ???????????????. ??????, ?????????????????? ?????? ?????? ?????? ??????????????? ??? ?????? ????????? ???????????????. ??? ?????? ???????????? ???????????? ??????????????? ?????????????????? ????????? ??? ?????? ??????????????? ????????? ????????????, ??? ?????? ?????? ??????????????? ???????????? ??? ????????? ????????? ????????? ??? dorsolateral prefrontal cortex (dlPFC) ????????? medial prefrontal cortex (mPFC) ????????? ????????? ???????????? ???????????? precuneus ????????? ????????? ????????? ?????????. ??? ????????? ?????? ?????? ???????????? ???????????? ???????????? ????????? ?????? ????????? ??????????????? ???????????? ????????? ???????????? ????????? ?????? ?????? ????????? ????????? ???????????? ????????? ????????? ???????????? ????????? ??????????????? ???????????? ?????? ????????? ?????? ?????? ????????? ??? ?????????. ??????, ???????????? ?????? ?????? ??????????????? frontal??? temporal ????????? ???????????? ?????????????????? ??? ????????? ?????? ?????? ?????? ???????????? ?????? ????????? ?????? ???????????? ?????? ????????? ?????? ?????? ????????? ??? ?????????. ??? ?????? ??????????????? ?????? ????????? ?????? ??????????????? ???????????? ?????? ????????? ????????? ????????? ?????? ???????????? ???????????? ?????? ??????(machine learning) ????????? ???????????? ????????? ?????? ????????? ???????????? ????????? ???????????????. ???????????? ?????? ????????? ?????? ?????? 1.5??? ????????? ?????? ????????? 100 ms ???????????? 500 ms ????????? window??? ????????? theta (1-4 Hz), alpha (8-12 Hz), low-beta (8-12 Hz), high-beta (12-30 Hz), gamma (30-55 Hz) ?????? ?????? ????????? ??????????????? ????????? ???????????? ????????? ??????????????? ??????????????? ?????? ????????? ???????????? ???????????? ????????? ?????? Fisher score??? ????????? ???????????????. ???????????? LDA (Linear Discriminant Analysis)??? ??????????????? 10 by 10-fold cross-validation??? ???????????? ?????? ???????????? ???????????????. ??? ?????? ?????? ?????? ?????? ????????? 22????????? ?????? 74.47% ???????????? ?????? ????????? ???????????? ????????? ??? ?????????. ????????? ?????? ????????? frontal??? temporal ????????? ?????? ???????????? ????????? ??????????????? alpha ???????????? ?????? ?????????. ??? ?????? ??????????????? ????????? ????????? ??????????????? ??? ?????? ????????? ?????? ??? ?????? ????????? ??????????????????. ????????? ??? 20????????? ?????? ?????? ????????? ??????????????? ????????? ?????? ?????? ???????????? ???????????? ?????? 5????????? ?????? ???????????? ???????????? ?????? 5????????? ???????????? ??? ????????? ??? ??? ????????? ???????????? ????????? ????????? ??????????????????. ??? ?????? superior temporal gyrus, middle temporal gyrus, precentral gyrus, superior parietal lobule, precuneus ????????? ????????? ????????? ?????????????????? ??? ????????? ????????? ??????, ??????, ??????, ?????? ????????? ???????????? ???????????? ????????? ??????. ??? ?????? ??????????????? ?????? ????????? ?????? ??????????????? ????????? ????????? ????????? ????????? ???????????? ?????? ??????(machine learning) ????????? ???????????? ???????????? ?????? ????????? ???????????? ????????? ???????????????. ????????? ???????????? 1.5??? ????????? ?????? ????????? 100 ms ???????????? 500 ms ????????? window??? ????????? theta (1-4 Hz), alpha (8-12 Hz), low-beta (8-12 Hz), high-beta (12-30 Hz), gamma (30-55 Hz) ?????? ?????? ????????? ??????????????? ????????? ???????????? ????????? ??????????????? ??????????????? ?????? ????????? ???????????? ???????????? ????????? ?????? Fisher score??? ????????? ???????????????. ???????????? LDA??? ??????????????? 10 by 10-fold cross-validation??? ???????????? ?????? ???????????? ???????????????. ??? ?????? ?????? ????????? 44????????? ?????? 68.41% ???????????? ?????? ?????? ????????? ???????????? ????????? ??? ?????????. ????????? ?????? ????????? frontal??? occipital ????????? ?????? ???????????? ????????? ?????? ????????? theta ???????????? ?????? ?????????. ??? ?????? ??????????????? ???????????? ?????? ?????? ?????? ????????? ???????????? ????????? ????????? ????????? ????????? ?????? ?????? ?????? ??????????????? ??? ????????? ?????? ????????? ???????????????. ?????? ?????? ???????????? ??????, ?????????, ????????? ???????????? ?????? ????????? ?????? ??????????????? ??? ????????? ???????????? ?????? ????????? ??????????????? ?????? ????????? ?????? ??? ????????? ???????????? ?????? ?????? ?????? ????????? ???????????????. ??? ?????? ????????? ??????????????? ????????? ????????? ?????? ???????????? ???????????? ???????????? ????????? ?????????.Various brain regional activities are activated during a consumer???s purchase decision-making process. The process is associated with the visual process of evaluating product design and emotional process of feeling a positive emotion or negative effect. Also, according to the cognitive process, they are deliberating about alternatives and selecting the best option. In addition, rewards such as tasty food and reasonable costs can have an influence on buying decisions, and previous experience with a product is also correlated with the consumer???s purchase decision. Traditional marketing methods such as marketing surveys and choice simulations have been used to estimate the uncovered intentions of consumers before releasing a product. However, these survey data are confounded by participant cognitive effects and show low accuracy. To get unpolluted responses and develop reliable, innovative marketing tools, researchers are trying to apply neuroscience methods. In the present study, the author investigated consumers??? cortical activation during purchase decision making using EEG. In the first study, the author identified the participants??? brain source activities during a virtual shopping task. In the virtual shopping task, the participants make purchase decisions considering products, brand logos, and prices. The participants were divided into two groups: a control group and an observation group, and product types were divided into social products and non-social products according to brand logos. The author investigated how consumers??? purchasing decisions are affected by the observations of others in behavioral and cortical source activities. In addition, the author investigated brain source activities in the process of purchasing by using EEG. In the behavioral results of ethical consumption, the observation group purchased more social products than non-social products regardless of price levelon the other hand, the control group showed a tendency to hesitate to buy expensive products regardless of the product type. In source activation results, the control group activated more in the medial prefrontal cortex (mPFC) and then deactivated more in the dorsolateral prefrontal cortex (dlPFC). On the other hand, the observation group activated more in the precuneus. In other source activity results, frontal and temporal regions were activated more during the final purchase decision. In other words, the moral decision-making process is associated with the emotional process and cognitive process, and the observation of others modulated determining behavior and the decision-making process. Also, the purchase decision-making process is associated with the decision-making process, cognitive process, and concerns about risks. In the second study, the author estimated consumers??? purchase behavior using an EEG signal and machine learning method. EEG features frequency band powers were extracted from 1500-ms-length EEG signals (500 ms moving window, 100 ms lag). The Fisher score was used to prevent overfitting of a classifier constructed from training data. Classification accuracy was calculated using 10 by 10-fold cross-validation and a Linear Discriminant Analysis (LDA) classifier. In the results, the author estimated consumer purchase decisions using EEG signals with 74.47% classification accuracy. The features extracted from frontal and temporal regions and the alpha band were selected as the best features. In the third study, the author investigated the neuronal activity of the consumer???s brain in the process of valuation of products by using EEG. When consumers evaluate the price of products, they evaluate the product???s appearance. Twenty food items were prepared, and each participant selected high-value products and low-value products. In valuation source activity results, temporal cortex (superior temporal gyrus and middle temporal gyrus) and parietal cortex (superior parietal lobule, precentral gyrus, and precuneus) regions were activated more while evaluating products with a high price. These regions are associated with the complex evaluation process and are associated with memory, rewards, emotion, and visual valuation. In the last study, the author predicted the consumer???s valuation of products while they evaluated product images using EEG signals. Features frequency band powers were extracted from 1500-ms-length EEG signals (500 ms moving window, 100 ms lag). The Fisher score was used to prevent overfitting of a classifier constructed from training data. Classification accuracy was calculated using 10 by 10-fold cross-validation and a Linear Discriminant Analysis (LDA) classifier. In the results, the author estimated the consumer???s evaluation results using EEG signals with 68.41% classification accuracy. The features extracted from the frontal and occipital regions and theta band were selected as the best features. In the present study, the author investigated the cortical mechanisms involved in the consumer???s purchase decision-making process considering multiple components, product types, brand logos, and prices, anticipating more reliable marketing methods. It also predicted consumers??? final decision-making responses and value evaluation results using EEG signals. The author hopes that this will serve as a foundation for future studies in neuromarketing.Docto