## 4 Results and Discussion
### Tests with Four Female Subjects with Different Brain Activity Conditions  
Four female subjects between 18 and 30 years of age were randomly selected to expand the sample and define the mobility performance of the electrode in the Chameleon-1 helmet. Participants were interviewed to obtain relevant information, such as age, health status before starting data collection, as shown in Table 4, and their medical history about any disease or injury related to the brain. Similar to the previous subjects, the EEG signals from female participants were processed using a bandpass filter (0.5-50 Hz), an optional notch filter (50 Hz and 60 Hz), and DC bias removal via common mode rejection (CMR) and high-pass filtering (0.5 Hz) to ensure signal stability. * Subject 6  
As in the male tests, the same methodology was carried out. The patient was first explained how the test would be performed (see Figure 23(a)). The patient was told that the test would last 5 min, which was divided into two stages of 3 min of concentration and 2 of relaxation. The patient was briefed on the software to be used (see Figure 23(b)), and a dedicated session was provided to address any questions. Figure 24(a) shows the electrical activity of the brain. The voltage detected over time by electrodes F3 and F4 is presented. This is generated in a sample of 5 s. It should be noted that there were no data losses during the test, and the voltage recorded during the test is within a normal range. Figure 24(b) provides a sample of the data recorded from the patient, showing the amplitude as a function of frequency. The patient shows a greater amplitude in the alpha and theta bands than in the others. \begin{table}
\begin{tabular}{l l l} \hline \hline
**Patient** & **Gender** & **Health** \\ \hline Subject 6 & Female & Moderate stress \\ Subject 7 & Female & Moderate insomnia \\ Subject 8 & Female & Healthy \\ Subject 9 & Female & Healthy \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Data from female participants who used the Chameleon-1 helmet. Figure 23: **(a)** Power band, **(b)** focus widget of Subject 5. Figure 26a shows an instant of the test performed, where beta and gamma waves predominate, indicating a moderate level of stress, and a null presence of the delta band. During the concentration test, the patient was asked to solve mental mathematical exercises and to perform breathing exercises during the relaxation round. Figure 26b shows the record obtained using the focus widget, highlighting the state of concentration with a red line shown on the metric value graph as a function of time. Figure 24: (a) Helmet placement, (b) start-up of tests with Subject 6. Figure 25: (a) Time series, (b) FFT plot of Subject 6. Subject 7  
Figure 27a shows Subject 7, where the tests were conducted, and the data collection procedures were repeated. The same procedure was followed by collecting some relevant data from the patient, such as name, age, and a description of her health status at the time of starting the test. The helmet was then placed and adjusted, and its operation was explained (see Figure 27b). During the first round of testing, the widget is set to 50 microvolts as the range to properly observe the signal obtained in both channels F3 and F4 (see Figure 28a). Figure 27: (**a**) Helmet placement, (**b**) start-up of tests with Subject 7. Figure 26: (**a**) Power band, (**b**) focus widget of Subject 6. In Figure 28b, the signal is distributed as a function of frequency. Theta is observed to have a greater presence. In the concentration test, Figure 29a shows an increase in the delta and theta bands along with beta and gamma, suggesting a combination of insomnia and stress. Figure 29b shows that the patient has difficulty maintaining a constant state of concentration. During the relaxation round, the patient did not show any difficulty in performing the test. Figure 28: (a) Time series, (b) FFT plot of Subject 7. Figure 29: _Cont._  
* Subject 8  
Figure 30 shows the penultimate patient (test Subject 8).