The Influence of Specific Sounds on Cognitive Function and the Mediating Role of Emotions

Prolonged exposure to noisy environments can exacerbate irritability and boredom, impacting individuals’ emotional well-being and cognitive functioning. Pulsed sounds posed an even greater threat by inducing heightened emotional stress and arousal, increasing the likelihood of human error and potentially leading to catastrophic consequences. On a neural level, pulsed sound stimulation affects brain activity by engaging regions such as the prefrontal cortex and hippocampus. Given these impacts, this study aims to investigate the neural mechanisms underlying the effects of pulsed sound on attention processing and working memory. Specifically, we seek to establish a causal model linking sound exposure, cognitive performance, and emotional responses. We aim to identify the specific parameters of pulsed sounds—such as frequency, loudness, and pulse width—that disrupt normal cognitive functioning and interfere with brain activity rhythms, ultimately elucidating how pulsed sounds affect attention and executive control processes. Participants were exposed to eight different types of pulsed sound stimuli, varying in repetition frequency (50 Hz and 100 Hz), relative loudness (−12 dB and −24 dB), and pulse width (10 μs and 50 μs). The results indicated that pulsed sound stimulation significantly impaired attention processing, particularly under low repetition frequency and high loudness conditions. Specifically, larger amplitudes in the N2pc and N400 components were observed in the prefrontal cortex. The N2pc component is critical for target selection and attention allocation, reflecting the shift of attention from non-target to target stimuli. Additionally, pulsed sound stimulation impaired working memory, most notably under low repetition frequency and high loudness. Under these conditions, the P300 and LPP components in the frontal cortex exhibited altered amplitudes. The P300 component, associated with allocating attentional resources and cognitive evaluation, reflects the individual’s ability to detect and process targets. The disruption of P300 activity suggests that pulsed sounds interfere with target retrieval processes. Meanwhile, the LPP component, linked to the maintenance and updating of working memory goals, showed an increase in amplitude, indicating that pulsed sounds increased the cognitive load, as the brain required more resources to evaluate complex stimuli. The findings offer critical insights into how pulsed sound affects both attention processing and working memory, highlighting the broader implications of environmental noise on cognitive performance and mental health. Moreover, the results have practical applications, offering a scientific basis for improving individuals’ adaptability to environmental noise. Through this research, we aim to provide both theoretical insights and technical support for enhancing human performance and safety in noisy environments.