Tehran University of Medical Sciences Auditory and Vestibular Research 2423-480X 0 0 2025 10 11 1486 1486 Sanaz Solotanparast PhD student of Iran university of medical science Reyhane Toufan Rehabilitation Research Center, Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran Saeed Talebian Motor Control Laboratory, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran. Akram Pourbakht Rehabilitation Research Center, Department of Audiology, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran 2025 08 04 2025 10 08 Background and aim:: The concept that recognizing sound regularities plays a major role in the segregation of auditory streams has lately gained significant interest. Thus, this study was designed to investigate how temporal and spectral regularities incorporated into the background auditory stream affect auditory stream segregation. Methods: An indirect measure of auditory streaming task (i.e., detecting rare-level targets) was implemented in twenty-five healthy young adults. Participants were presented with two concurrent auditory streams involving foreground and background ones. Participants were instructed to detect rare-level targets in the foreground stream during three experimental conditions. These conditions vary based on the background auditory stream, which contained repeating temporal and spectral patterns alongside elements of randomness. Results: Temporal and spectral regularities of the background auditory stream significantly increased the hit rate compared to random structure. Notably, this effect of regular cues on target detection and, possibly in turn, stream segregation was significantly greater for temporal compared to spectral regularities. Conclusion: These findings showed that incorporating temporal or spectral regularities in the background auditory stream facilitated target detection and, possibly in turn, stream segregation. This perceptual regularity benefit was greater for temporal regularities than spectral regularities. These findings might present primary evidence for distinct facilitating effects of various theoretical frameworks of sound feature regularities on auditory streaming. https://avr.tums.ac.ir/index.php/avr/article/view/1486