## 3 Results
### Bioimpedance Measurement  
Since it was aimed to derive a map of the impedance variation using dielectric properties of the cochlea tissue layers at various frequency values, the average impedance variation was extracted using (4). The impedance variation based on the frequency spectrum for the odd-numbered EA contacts is shown in Figure 6. The results for the border-placed and center-placed EA models are shown in Figure 6A,B, respectively. It is clearly shown that there is a fluctuation in impedance variations for all EA contacts based on different frequency values for both EA models. In all cases, there is an inversely proportional relationship between impedance variation and simulation frequency for both EA models. When the simulation frequency increases, the impedance variation shows the opposite trend. For example, the impedance variation is significantly reduced when the dielectric properties of the cochlea tissue layers at 100 MHz are used. This is valid for both EA models. For example, the recorded impedance value is about 1.3 k\(\Omega\) for 10 Hz simulation frequency, whereas this is about 0.8 k\(\Omega\) for 100 MHz simulation frequency for the E1 contact, as shown in Figure 6A. However, the impedance results are relatively higher for the border-placed EA model compared to the center-placed one. Also, there is a direct relationship between insertion depth and recorded bio-impedance amplitude. The impedance variation is relatively higher at the deeper locations of the cochlea for both  
Figure 5: The capacitive effect of the tissue using various simulation frequency steps for odd-numbered electrode contacts. (**A**) shows the results for the EA model that is placed at the border of the ST. (**B**) shows the results for the EA model that is placed at the center of the ST.  
EA models. The results for the deepest electrode contact (E1) are about 1.1 k\(\Omega\) and this value is about 0.85 k\(\Omega\) for the E15 based on 1 MHz simulation frequency, as shown in Figure 6A. As shown in Figure 6B, the same trend is observed with slightly lower variation. The impedance variations are 0.65 k\(\Omega\) and 0.47 k\(\Omega\) for the 1 MHz simulation frequency. This correlation is valid for all simulation frequency samples. Overall, the impedance increased with insertion depth and proximity to the inner wall of the cochlea. However, the lower impedance variation is recorded when the dielectric properties are used at the higher simulation frequency values for both EA models. Since the most important anatomical layer is the ST for the electrode insertion, the second step of the study was to parametrize the conductivity of the ST to identify the impact of these dielectric parameters on the outcome by comparing impedance results for the QS and TS methods based on various dielectric properties of the cochlea layers. The impedance results based on various conductivity (\(\sigma\)) values of the ST are recorded using different simulation frequencies for TS and the obtained results are compared with QS, as shown in Figure 7, to examine the capacitive effect on the outcome. This variation is recorded based on the border-placed EA model. The trends between impedance measures and simulation types are similar. When the conductivity of the ST increased, the lower impedance was measured for both simulation scenarios. The highest impedance value is recorded at the lowest conductivity, and this is valid for all simulations. To highlight, the recorded impedance variation is about 2.1 k\(\Omega\) and 0.75 k\(\Omega\) for the lowest and highest conductivity values, respectively (based on 10 MHz simulation frequency). Although the amplitude of the impedance slightly shows different trends after a certain simulation frequency level (e.g., 500 kHz), the results for the QS and TS methods are slightly identical for the frequency levels from 10 Hz to 100 kHz, as shown in all subplots in Figure 7. The maximum impedance is measured based on the deepest electrode contact (E1) for all simulation scenarios.