# Advancements in EEG Emotion Recognition: Leveraging Multi-Modal Database Integration
## 2 Database and Data Collection
### Experimental Setup  
Creating an appropriate experimental setup is crucial for obtaining reliable EEG data. The setup should provide a controlled and comfortable environment for participants to experience and express different emotional states. Proper instructions and stimuli presentation protocols should be implemented to elicit genuine emotional responses. The data acquisition methodology in this study centers on eliciting continuous emotional responses from participants, who are prompted to report and update their emotional states throughout the experiment [37]. Simultaneously, raw EEG signals are recorded using the EMOTIV EPOC+ headset, while facial expressions are captured via a webcam connected to the computer through a USB port. This multimodal approach aims to comprehensively capture emotional responses. Emotional elicitation is achieved through various stimuli, such as photographs, videos, short clips, or a combination of these mediums. High-quality EEG data acquisition is essential for accurate emotion recognition. It involves the proper placement of electrodes on the participant's scalp according to established standards (e.g., the 10-20 system [45]). Continuous monitoring of electrode signal quality is performed through the user interface which is reading the signal quality and battery level real-time values from the EMOTIV software. The objective here is to maintain the overall signal connectivity at 100 and the battery level above 70, as shown in the interface. Figure 3 shows the signal quality for all 14 electrodes on a scale of 1 to 4, where  
* 1 indicates no signal, suggesting that the electrode is most likely dead or disconnected;
* 2 indicates a very weak signal that is not usable;
* 3 indicates an acceptable signal reception;
* 4 indicates a good signal. The commencement of the recording process ensues upon activation of the \"Record\" button, leading to the visual presentation of the video on the display. Moreover, participants are mandated to provide informed consent through the execution of an agreement elucidating the nature of the data collection and the underlying rationale for the utilization \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **Clip 1** & **Clip 2** & **Clip 3** & **Clip 4** & **Clip 5** & **Clip 6** \\ \hline Happy & 47 & 50 & 49 & 61 & 54 & 56 \\ \hline Angry & 52 & 48 & 62 & 50 & 50 & 49 \\ \hline Sad & 83 & 55 & 42 & 47 & 58 & 58 \\ \hline Hungry & 50 & 66 & 63 & 55 & 33 & 45 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Experiment stimulus videos’ duration in seconds targeting different human emotions. of emotionally evocative videos. To streamline the experimental protocol, participants are furnished with an EPOC+ headset, featuring meticulously calibrated sensors with a moistening solution to ensure optimal connectivity. Placement of the headset on the participant's cranium is followed by the strategic positioning of a monitor at eye level, thereby enhancing attentiveness. A video camera is strategically positioned atop the display to capture the nuanced facial expressions of participants throughout the video sequences. The experimental paradigm unfolds through several distinct stages. Commencing with a 60 s relaxation video devoid of recording, participants subsequently engage with a sequence of videos categorized into emotional states including Happiness, Anger, Sadness, Hunger, and Pain. Each video within this array spans a temporal range of 33 to 83 s, with an average duration of 53.42 s. As participants progress through the experiment, they are systematically prompted to articulate the emotions or affective states elicited during the video exposure. This is achieved through the manipulation of designated keys on the keyboard, as illustrated in Figure 4. The baseline emotional state at the initiation of each video recording is predefined as \"Neutral\", affording participants the flexibility to modify their reported emotional state dynamically throughout the recording process.