## 4 Discussion
Based on the findings of this study, there is a difference in the results of the magnitude of the noise level within the type of noise, namely between the type of continuous noise and intermittent noise, which gives different results, thus proving that the type of noise and noise level can have an influence on the participants' attention. A study by [77] revealed that the Stroop effect and mental calculation performance in 50 dB of noise exposure increased compared to 70 dB of noise. Also, ref. [77] reported that noise exposure higher than 85 dB can cause vulnerability, fatigue, and stress. The results of this study are consistent with the finding that there is an association between low performance and high noise levels [16; 17]. Another study provides the results that the effects of noise at moderate levels are more harmful to accuracy, and that attention will be significantly affected by exposure to moderate levels of noise [15]. A study by [78] provides results indicating that sound intensity is significant to the average attentional beta signal. The analysis of cognitive aspects of stress in this study used the average results of alpha power spectrum density signals. An increase in the alpha band power spectrum along with a decrease in the beta band power spectrum leads to improved cognitive function [23]. An increase in alpha power indicates decreased brain activity (relaxing) [79]. In this study, the results of measuring the cognitive aspects of stress in Figure 7a,b showed that participants were in a relaxed condition (not experiencing stress) at a noise level of 65 dB at exposure to the type of continuous noise based on the largest power spectrum at the level of 65 dB, with the maximum point being at a log power of 41.31 \(\upmu\)V\({}^{2}\) at a frequency of 8.13 Hz. The power spectrum at 65 dB decreased to a minimum of 40.27 \(\upmu\)V\({}^{2}\) at 11.17 Hz. The higher the noise level, the more participants are in a state of not relaxing (stress). For the type of intermittent noise, participants at the 65 dB noise level are in a relaxed condition with the largest power spectrum at the 65 dB level, with the maximum point being at a log power of 39.44 \(\upmu\)V\({}^{2}\) at a frequency of 8.13 Hz. The power spectrum at 65 dB decreased to a minimum of 38.74 \(\upmu\)V\({}^{2}\) at 11.55 Hz. A noise level of 80 dB in the continuous noise type and 75 dB in the intermittent noise type has the lowest alpha signal power spectrum value, so participants are in a state of stress at those noise levels. The findings of this study revealed a significant relationship between noise type and noise level with cognitive performance in terms of participants' stress levels when exposed to noise. Studies by [24] showed that noise exposure is significant to job stress and negatively related to job satisfaction. Higher noise levels will cause stress, proving that noise conditions have a positive relationship with increased work stress, in line with the study by [27]. Other study findings also indicated that noise impacts cognitive performance and brain signaling as a stress-inducing factor [11]. In addition, noise level is an important factor that causes interference with cognitive performance, which means that low noise levels are less disruptive to performance than higher noise levels. It can be said that the findings of this study are consistent with the proposition that there is a relationship between poor performance and sound pressure levels [49]. Furthermore, due to increasing stress levels, noise also has a major impact on reaction ability and focus. The analysis of the cognitive aspects of mental workload in this study showed that at a noise level of 70 dB with a theta-to-alpha ratio value that increased from the noise level below, participants started mentioning how noise affected their mental workload. The results indicate a correlation between band ratios and mental workload stages, particularly between theta and alpha bands, aligning with the findings of [63; 80].