International Journal of Preventive Medicine (Int J Prev Med)2008-78021411202312182230ENDepartment of Occupational Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran1- Department of Occupational Health and Safety Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran2- Department of Occupational Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran3- Department of Ergonomics, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran4- Department of Biomedical Engineering, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran6- Department of Occupational Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran20231218<p>Bachground: Noise is one of the most important harmful factors in the environment. There are limited studies on the effect of noise loudness on brain signals and attention. The main objective of this study was to investigate the relationship between exposure to different loudness levels with brain index, types of attention, and subjective evaluation. Methods: Four noises with different loudness levels were generated. Sixty‑four male students participated in this study. Each subject performed the integrated visual and auditory continuous performance test (IVA-2) test before and during exposure to noise loudness signals while their electroencephalography was recorded. Finally, the alpha‑to‑gamma ratio (AGR), five types of attention, and the subjective evaluation results were examined. Results: During exposure to loudness levels, the AGR and types of attention decreased while the NASA‑Tax Load Index (NASA‑TLX) scores increased. The noise exposure at lower loudness levels (65 and 75 phon) leads to greater attention dysfunction than at higher loudness. The AGR was significantly changed during exposure to 65 and 75 phon and audio stimuli. This significant change was observed in exposure at all loudness levels except 85 phon and visual stimuli. The divided and sustained attention changed significantly during exposure to all loudness levels and visual stimuli. The AGR had a significant inverse correlation with the total score of NASA‑TLX during noise exposure. Conclusions: These results can lead to the design of methods to control the psychological effects of noise at specific frequencies (250 and 4000 Hz) and can prevent non‑auditory damage to human cognitive performance in industrial and urban environments.</p><p><span class="ej-journal-name" style="box-sizing: inherit; font-style: italic; font-weight: 500; color: #3b3030; font-family: 'Fira Sans', sans-serif; font-size: 14px; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">International Journal of Preventive Medicine<span> </span></span><span id="ej-journal-date-volume-issue-pg" style="box-sizing: inherit; color: #3b3030; font-family: 'Fira Sans', sans-serif; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><a style="box-sizing: border-box; color: #005b92; text-decoration: none; background-color: transparent; cursor: pointer; outline: 0px;" href="https://journals.lww.com/ijom/pages/currenttoc.aspx">14():125, November 2023.</a></span><span style="box-sizing: inherit; color: #3b3030; font-family: 'Fira Sans', sans-serif; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><span> </span>|<span> </span></span><span class="ej-journal-doi" style="box-sizing: inherit; font-style: italic; font-weight: 500; color: #3b3030; font-family: 'Fira Sans', sans-serif; font-size: 14px; font-variant-ligatures: normal; font-variant-caps: normal; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">DOI:<span> </span></span><span style="color: #3b3030; font-family: 'Fira Sans', sans-serif; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: #ffffff; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;">10.4103/ijpvm.ijpvm_395_22</span></p><p> </p><p>Corresponding Author: Dr. Mohammad Javad Jafari,</p><p>E‑mail: mj.jafari1952@gmail. com</p><p>You can also search for this author in: <a title="PubMed" href="https://pubmed.ncbi.nlm.nih.gov/?term=%28%28Mohammad+Javad+Jafari%5BAuthor%5D%29+AND+%28Shahid+Beheshti+University+of+Medical+Sciences%5BAffiliation%5D%29%29">PubMed</a>  <a title="Google Scholar" href="https://scholar.google.com/citations?user=K5q-l48AAAAJ&amp;hl=en&amp;oi=ao">Google Scholar</a></p>http://ijpm.mui.ac.ir/index.php/ijpm/article/view/2881http://ijpm.mui.ac.ir/index.php/ijpm/article/download/2881/717718722