Well-being is an essential concept in cosmetics, but its complexity makes it very difficult to measure. The goal of the present study was to use electroencephalography (EEG) to compare the emotions induced by the application of two cosmetic products, and to offer to the experimenter a real-time representation of the participants’ emotional state. Fifteen female subjects participated in a cross-over study. Two cosmetic products of similar consistency were compared and applied from the dominant hand to the non-dominant hand. During the application, the neural activity of each participant was recorded with EEG. We found that the most appreciated product was the one that induced emotions with the most positive valence and the higher arousal, as recorded by EEG. Moreover, the videos recorded of each participant allowed us to attest to the differences in emotion processing for each product in real-time. This exploratory study shows that EEG can be successfully used to assess the emotions induced by the application of a cosmetic product, and in real-time. This technique could be a useful adjunct to other methods of examining emotions, such as observational experiments, surveys, and questionnaires.
The study of interbrain coupling in a group of people attending a concert together is a favorable framework to estimate group emotions and more precisely emotional connection between people sharing situations in the same environment. It offers the advantage of studying interactions at the group level. By recording the cerebral activity of people from an audience during a concert using electroencephalography, we previously demonstrated that the higher the emotions and the physically closer the people were, the more the interbrain synchrony (IBS) was enhanced. To further investigate the parameters that shaped inter-brain synchronization in this context, we now focus on the emotional dynamics of the group as a whole by identifying specific moments in the concert that evoked strong or weak emotions, as well as strong or weak emotional cohesion between individuals. We demonstrated that audience interbrain synchrony is mainly associated with experiencing high musical pleasure and that the group emotional cohesion can enhance IBS, but alone is not the major parameter that shapes it in this context.
Risk-taking is part of the multidimensional nature of impulsivity, consisting of an active engagement in behaviors or choices with potentially undesirable results, with probability as the cost for an expected reward. In order to understand the neurophysiological activity during risky behavior and its relationship with other dimensions of impulsivity, we have acquired event-related-potential (ERP) data and self-reported impulsivity scores from 17 non-clinical volunteers. They underwent high-resolution electroencephalography (HR-EEG) combined with an adapted version of the Balloon Analogue Risk Task (BART), and completed the Barratt Impulsiveness Scale (BIS-10) and the Urgency, Premeditation, Perseverance, Sensation Seeking, Impulsive Behavior Scale (UPPS). The ERP components were sensitive to valence (FRN, P300) and risk/reward magnitude (SPN, RewP). Our main finding evidenced a positive correlation between the amplitude of the P300 component following positive feedback and both the global UPPS score and the (lack of) perseverance UPPS subscale, significant for several adjacent electrodes. This finding might suggest an adaptive form of impulsive behavior, which could be associated to the reduction on the difference of the P300 amplitude following negative and positive feedback. However, further investigation with both larger clinical and non-clinical samples is required.
Over the years, several publications have proposed that musical sound could be an ancestral emotional way of communication, thus positing an ancestral biological function for music. Understanding how musical emotions, and the pleasure derived from music regardless of the musical valence, can be shared between individuals is a fascinating question, and investigating it can shed light on the function of musical reward. Is the pleasure felt at the individual level transmitted on a collective level? And if so, how? We investigated these questions in a natural setting during an international competition for orchestra conductors. Participants (n=15) used a dedicated smartphone app to report their subjective emotional experiences in real time during a concert. We recorded participant’s electrodermal activity (EDA) and cerebral activity with electroencephalography (EEG). The overall behavioral real time ratings suggest a possible social influence on the reported and felt pleasure. The physically closer the participants, the more similar their reported pleasure. We estimated the inter-individual cerebral coherence, which indicates the degree of mutual cerebral information between pairs of participants in the frequency domain. The results show that when people simultaneously reported either high or low pleasure, their cerebral activities were closer than for simultaneous neutral pleasure reports. Participants’ skin conductance levels were also more coupled when reporting higher emotional degrees simultaneously. More importantly, the participants who were physically closer had higher cerebral coherence, but only when they simultaneously reported intense pleasure. We propose that mechanisms of emotional contagion and/or emotional resonance could explain why a form of ‘emotional connecting force’ could arise between people.