Lina Reiss – reiss@ohsu.edu
Instagram: @reiss.lina
Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239, United States
Stephen David
Bluesky: @stephenvdavid.bsky.social
Oregon Health and Science University
Michela Mondesir
Oregon Health and Science University
Miles Carter
Instagram: @meelos22
Oregon Health and Science University and University of Pittsburgh.
Popular version of 1aAB2 – Neural correlates of binaural fusion
Presented at the 190th ASA Meeting
Read the abstract at https://eppro01.ativ.me/web/planner.php?id=ASASPRING2026
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
If you listen to two different sounds that are similar in pitch across the ears, something strange happens. The two sounds blend perceptually to create an illusion of a new sound, similar to what happens with different colors across the eyes.
For example, if you listen here with stereo headphones to the vowels “ah” as in hot and “ee” as in heed, spoken by two different talkers with different voice pitch – a male talker and a female talker – you will hear two vowels.
Figure 1. Perception when two different vowels are played to the two ears at different pitch. Play different pitch example. Note: Stereo headphones are necessary to experience the illusion
But if these same vowels are spoken by the same talker, you will experience something called binaural fusion (Reiss and Molis, 2021). Instead of hearing two different vowels, you will hear a single new vowel. This new vowel will be a blend of the two original vowels, something in between like “eh” as in head.
Figure 2. Perception when two different vowels are played to the two ears at the same pitch. Play same pitch example. Note: Stereo headphones are necessary to experience the illusion
This illusion is not confined to steady sounds, but also happens for sounds that are fluctuating, such as a tone that is fluctuating in one ear and steady in the other ear. This makes localization of the fluctuating tone difficult.
While we know that people experience binaural fusion, we don’t know what happens in the brain so that some sounds fuse while others are heard as distinct. It’s hard to measure detailed brain activity in humans, so we are now studying what happens in the brain of animals, in this case ferrets, when they experience the same illusion. The first thing we had to do was demonstrate that ferrets perceive these illusions the same way as humans. For vowels, ferrets were first trained to indicate when they heard the vowel “eh”, and to ignore the vowels “ah” and “ee”. When “ah” and “ee” were played to the two ears at the same pitch, the ferrets responded that they heard “eh”. Similarly, for fluctuating tones, ferrets were trained to indicate the side where they heard the fluctuating tone, and they experienced the same difficulties as human listeners.
As a next step, recordings from cells in the brain will reveal how brain activity leads to these illusory phenomena. Binaural fusion and the converse, binaural fission, are important to understand because together they underlie how the brain groups components of sound that belong to one source, such as a single talker, and separates those that belong to different sources, such as other talkers (Bregman, 1990; Bronkhorst, 2000).
It is shown that people with hearing loss, including those with cochlear implants, often experience excessive binaural fusion, and fuse voices of different pitch together (Reiss et al., 2014; 2017; 2018). Excessive binaural fusion explains a large portion of difficulties with understanding speech in noisy environments (Oh et al., 2022; 2023). Understanding how brain circuits encode binaural fusion and fission will show us how to train or rewire the brain to help people with hearing loss and other auditory processing disorders.
In the meantime, think about how you can come up with other new illusory sounds by combining two different sounds of the same pitch!
Works cited
Bregman, A. S. (1990). Auditory Scene Analysis (MIT Press, Cambridge, MA).
Bronkhorst, A. W. (2000). The cocktail party phenomenon: A review of research on speech intelligibility in multiple-talker conditions. Acta Acustica united with Acustica, 86(1), 117-128.
Oh, Y., Hartling, C. L., Srinivasan, N. K., Diedesch, A. C., Gallun, F. J., & Reiss, L. A. J. (2022). Factors underlying masking release by voice-gender differences and spatial separation cues in multi-talker listening environments in listeners with and without hearing loss. Frontiers in neuroscience, 16, 1059639.
Oh, Y., Srinivasan, N.K., Hartling, C.L., Gallun, F.J., and Reiss, L.A.J. (2023). Differential effects of binaural pitch fusion range on the benefits of voice gender differences in a ‘cocktail party’ environment for bimodal and bilateral cochlear implant users. Ear Hear. 44(2), 318–329.
Reiss, L. A., Fowler, J. R., Hartling, C. L., and Oh, Y. (2018) Binaural pitch fusion in bilateral cochlear implant users. Ear Hear. 39(2), 390-397.
Reiss, L.A., Ito, R.A., Eggleston, J.L., and Wozny, D.R. (2014). Abnormal binaural spectral integration in cochlear implant users. J. Assoc. Res. Otolaryngol., 15(2), 235–248.
Reiss, L.A.J., and Molis, M.R.. (2021) An Alternative Explanation for Difficulties with Speech in Background Talkers: Abnormal Fusion of Vowels across Fundamental Frequency and Ears. J. Assoc. Res. Otolaryngol., 22(4): 443-461.
Reiss, L.A., Shayman, C.S., Walker, E.P., Bennett, K.O., Fowler, J.R., Hartling, C.L., Glickman, B., Lasarev, M.R., and Oh, Y. (2017). Binaural pitch fusion: Comparison of normal-hearing and hearing-impaired listeners. J.Acoust. Soc. Am., 141(3), 1909–1920.
Pinar Erturk – perturk@bu.edu
Speech, Language and Hearing Sciences, Boston University, Boston, Massachusetts, 02215, United States
Virginia Best – ginbest@bu.edu
Speech, Language and Hearing Sciences
Boston University
Popular version of 3aPP6 – Spatial Perception with Over-the-Counter Hearing Aids
Presented at the 190th ASA Meeting
Read the abstract at https://eppro01.ativ.me/web/planner.php?id=ASASPRING2026
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Hearing aids help millions of people hear speech more clearly. But they may quietly reshape something else: your sense of where sounds are coming from. A new wave of affordable, over-the-counter (OTC) hearing aids is now available and they come in a wide variety of shapes and sizes and styles. Our study aims to understand what characteristics of hearing aids support (or disrupt) sound localization.
The ability to localize sound (knowing whether a car is approaching from the left or right, whether a voice is coming from in front of you or behind) is something most people take for granted. This spatial awareness relies on subtle acoustic cues available at the two ears. These cues can easily be disrupted by devices placed in or around the ear. Listeners with mild hearing loss, the very group that OTC devices are designed for, may be particularly vulnerable to these distortions, since they have relatively good sensitivity to sounds and their detailed characteristics.
To investigate, 14 adults with normal hearing were fitted with four different OTC devices representing a range of styles currently on the market: Lexie B2 Plus (a traditional behind-the-ear style), Eargo (an invisible in-the-canal style) and Apple Air pods Pro 2 (representing the growing category of consumer earbuds that can function as hearing aids).
Each participant completed a set of spatial listening tasks while wearing each device, and also without any device as a baseline. The tasks were designed to probe three distinct aspects of spatial perception: (1) Azimuth identification tests whether a listener can accurately judge the horizontal direction of a sound source; (2) Front-back discrimination asks whether listeners can tell whether a sound is coming from in front of them or behind; (3) Sound externalization refers to whether sounds are perceived as coming from the outside world, or from inside the head like when listening over headphones.
The results were clear: every OTC device tested disrupted spatial perception (Figure 1). However, the specific aspects of spatial perception that were affected, and the extent of the disruption, depended on the device and on the individual. By examining these patterns, we are able to make inferences about which features of OTC hearing aids support spatial perception and which features have a disrupting effect.
Figure 1. Mean absolute externalization ratings across hearing aid conditions, with individual participant data overlaid.
As the market for consumer hearing devices continues to grow, it is important to understand how they affect all aspects of hearing, not just speech clarity. This will be essential for helping people make informed choices about hearing aids and for designing more natural-sounding hearing aids in the future.
Sabine C. Langer – s.langer@tu-braunschweig.de
TU Braunschweig, Institute for Acoustics and Dynamics, Braunschweig, Lower Saxony, 38108, Germany
LinkedIn: http://www.linkedin.com/in/sabine-langer-6450a033a
Popular version of 4aEA2 – Toward acoustics-oriented aircraft design for highly integrated transport aircraft
Presented at the 190th ASA Meeting
Read the abstract at https://eppro01.ativ.me/web/index.php?page=Session&project=ASASPRING2026&id=4071512
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
“Noise must one day be fought as bitterly as cholera and the plague,” Robert Koch the German bacteriologist famously said at the turn of the 20th century. He was right—today we know that too much noise can harm our well-being and lead to real health problems.
Traditionally, we’ve tried to “combat” noise with after-the-fact abatement measures. But wouldn’t it make more sense to prevent noise before it ever starts? That’s why, decades ago, ISO standards laid out rules for low-noise design across the entire sound-generation chain—from the source, through all the transmission paths, to the listener. Yet in our modern, highly technical, urban world, these low-noise principles alone aren’t enough: noise challenges are still growing.
Take traffic, for example. In cities around the world, countless people are constantly disturbed by the noise of cars, trains and aircraft. We need to step up our efforts with a full paradigm shift toward acoustics-oriented design—a strategy that defines desired sound characteristics right at the start of product development and then uses methods and tools to predict, create, implement, and assess those acoustic properties throughout the entire process.
Figure 1: From noise abatement to acoustics-oriented design in all phases of product development (Image adapted from Rothe[1]) and Langer [2])
That sounds great in theory—but how do you predict what a complex system like an aircraft will sound like before you even build a prototype? The answer is advanced computer modelling, efficient simulation and perceptual-driven assessment. These tools let us forecast how a future aircraft will sound like and let us even listen to it.
Figure 2: Enabler for acoustics-oriented design: Modeling, Simulation, Assessment (Image adapted from Langer [3] )
Implementing acoustics-oriented design, we make sure that tomorrow’s aircraft not only burn less fuel and emit fewer pollutants but also sound pleasant—both inside the cabin and out on the ground.
[1] Rothe, S.: Design and placement of passive acoustic measures in early design phases. Schriften des Instituts für Akustik. 2022
[2] Langer, S.: Paving the path for acoustics-oriented design. ISCV31, 2025
[3] Thoma, J.; Delfs, J.: Proskurov, S.; Langer, S. C.: Cabin acoustics in preliminary aircraft design with propulsion pressure field excitation. DAS-DAGA2025/629, 2025.
Deanna Sharpe – deannas0730@gmail.com
Instagram: @deanna._.s
Emory University, Atlanta, Georgia, 30058, United States
Mishaela DiNino
dinino@buffalo.edu
University at Buffalo
Popular version of 1pPP13 – Auditory Emotional Attention in Anxiety Disorders
Presented at the 190th ASA Meeting
Read the abstract at https://eppro01.ativ.me/web/page.php?page=IntHtml&project=ASASPRING2026&id=4082942
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Imagine you’re eating with your friend, when you both suddenly get distracted by someone angrily arguing with their date. The conversation captured your attention due to its emotional content. This attention-grabbing experience of an angry conversation may intensify for those with anxiety disorders.
In hearing, auditory selective attention refers to the process of focusing on one sound while suppressing attention to other sounds. This is important for hearing speech in noise and focusing on conversations in social settings. Exploring how anxiety may affect auditory attention is critical to understanding how anxiety disorder symptoms affect everyday social situations.
Generalized anxiety disorders are characterized by excessive, clinically significant worry, whereas social anxiety disorders are marked by persistent fear or anxiety about social situations (American Psychiatric Association, 2022). People with anxiety disorders tend to have attention biases, especially in response to threat.
Figure 1. Visualization of Auditory Emotional Attention Process.
For example, research with visual stimuli, such as written words, demonstrates that individuals with anxiety exhibit an attention bias toward negative stimuli over neutral or positive stimuli (Fox, 1993; Yiend & Mathews, 2001). However, much less is known about a potential bias to sound in anxiety disorders. Negative emotion in speech can be conveyed through rhythm, stress, and intonation, otherwise known as prosody (Ladd, 2008). So, if individuals with anxiety disorders are biased toward negative sounds, like angry voices, that could interfere with auditory selective attention, making it difficult for them to follow conversations when others speak around them.
In this study, young adults listened to a target sentence while ignoring a second sentence played simultaneously. In the “Emotional Target” condition, the target sentence was spoken with emotional prosody (happy, sad, or angry-sounding), with a neutral (no prosody) distractor sentence. In the “Emotional Distractor” condition, the target was neutral, whereas the distractor was emotional. Additionally, participants completed the Generalized Anxiety Disorder Scale (GAD-7) (Spitzer et al., 2006) and the Social Interaction Anxiety Scale (SIAS) (Heimberg et al., 1992). We expected that individuals with greater symptom severity for generalized and social anxiety would have more difficulty attending to neutral speech while ignoring emotional speech.
Figure 2. Auditory Emotional Attention Task Instructions.
Instead, our findings demonstrated that people with greater generalized anxiety disorder symptoms performed significantly better on both conditions of the task. Individuals with higher levels of social anxiety symptoms also demonstrated significantly better performance on the Emotional Target condition. While these results don’t align with our hypothesis, they are consistent with increased vigilance in anxiety disorders (Bögels & Mansell, 2004; Vassilopoulos, 2005).
Our study findings suggest that individuals with generalized anxiety and social anxiety disorders experience greater auditory salience to emotionally prosodic stimuli. This means they’re better able to both attend to and ignore emotional stimuli than are individuals without these disorders. Thus, further research on auditory emotional attention will help understand attentional bias and provide insight into the treatment of anxiety disorders.
But until then, the next time you’re in a noisy room, consider which sounds capture your attention!
Works Cited
American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR). American Psychiatric Association Publishing. https://doi.org/10.1176/appi.books.9780890425787
Bögels, S. M., & Mansell, W. (2004). Attention processes in the maintenance and treatment of social phobia: Hypervigilance, avoidance and self-focused attention. Clinical Psychology Review, 24(7), 827–856. https://doi.org/10.1016/j.cpr.2004.06.005
Fox, E. (1993). Allocation of visual attention and anxiety. Cognition and Emotion, 7(2), 207–215.
Heimberg, R. G., Mueller, G. P., Holt, C. S., Hope, D. A., & Liebowitz, M. R. (1992). Assessment of anxiety in social interaction and being observed by others: The Social Interaction Anxiety Scale and the Social Phobia Scale. Behavior Therapy, 23(1), 53–73.
Ladd, D. R. (2008). Intonational phonology (2nd ed). Cambridge university press.
Spitzer, R. L., Kroenke, K., Williams, J. B., & Löwe, B. (2006). A brief measure for assessing generalized anxiety disorder: The GAD-7. Archives of Internal Medicine, 166(10), 1092–1097.
Vassilopoulos, S. P. (2005). Social anxiety and the vigilance-avoidance pattern of attentional processing. Behavioural and Cognitive Psychotherapy, 33(1), 13–24.
Yiend, J., & Mathews, A. (2001). Anxiety and attention to threatening pictures. The Quarterly Journal of Experimental Psychology Section A, 54(3), 665–681.
Andrew Brown – andrewdb@uw.edu
University of Washington, Department of Speech and Hearing Sciences, Seattle, WA, 98105, United States
Additional authors: DJ Audet Jr, Aoi A. Hunsaker, Mallory Butler, Carol Sammeth, Alexandria Podolski, Theodore F. Argo, David A. Anderson, Nathaniel T. Greene,
Popular version of 2pNSa4 – Two-dimensional sound localization during hearing protector use in a large sample of human listeners
Presented at the 189th ASA Meeting
Read the abstract at https://eppro02.ativ.me//web/index.php?page=Session&project=ASAASJ25&id=3982069
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
In noisy professions – from manufacturing to the military – hearing protection and perception are often at odds. The sense of hearing normally enables listeners to detect and locate sounds arriving from any direction – an especially valuable ability in settings with low visibility (darkness, fog, smoke), visual clutter, or in which important sound sources may be outside the field of vision altogether, whether off in the distance or “right behind you!” However, when noisy settings demand the use of hearing protectors (usually earplugs or earmuffs), the ability to determine sound direction is reduced. Hearing protectors lower the level of transmitted sound – their designed purpose – but they also change the quality of the transmitted sound, disrupting the subtle bits of acoustic information the brain relies on to determine sound direction. This means listeners may confuse forward and rearward sounds, or struggle to locate sounds overhead. The trade-off between protection and perception can contribute to disuse of hearing protectors in critical settings where situational awareness and personal safety may be acutely valued above long-term hearing health.
Methods to evaluate hearing protector impacts have varied widely across previous studies; hearing protectors come in many shapes and sizes, and directional hearing ability varies across people even before hearing protectors enter the picture. Here, in an effort to identify key factors that mediate hearing protector impacts, we measured directional hearing during hearing protector use in a large sample of listeners across two different sites (130 subjects enrolled study-wide). Listeners were asked to orient to sounds that varied in horizontal and vertical location while wearing a variety of commercially available hearing protector styles, with orientation accuracy measured using wireless sensors.
All hearing protectors reduced directional hearing ability, but variation across devices pointed to key variables that may impact performance – and may be captured using relatively simple acoustic measurements. This work is part of an effort to develop metrics beyond the industry-standard “Noise Reduction Rating” that consumers and hearing conservation professionals alike might use to select job-appropriate hearing protectors, and that hearing protection manufacturers might leverage to design and build better devices.
This work was funded by the US Department of Defense Joint Warfighter Medical Research Program.
Alaa Algargoosh – algargoosh@vt.edu
Virginia Polytechnic Institute and State University (Virginia Tech), Perry St, Blacksburg, VA, 24061, United States
Megan Wysocki
Virginia Polytechnic Institute and State University (Virginia Tech)
Amneh Hamida
RWTH Aachen University.
Popular version of 1pNSa4 – Cognitive Restoration in Virtual Interactions with Indoor Acoustic Environments
Presented at the 189th ASA Meeting
Read the abstract at https://eppro02.ativ.me//web/index.php?page=Session&project=ASAASJ25&id=3977035
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
People often associate restorative experiences with nature: the sound of birds, wind, or flowing water. But what if indoor spaces could offer their own kind of mental escape, not through what we see, but through how we interact with sound?
This idea began with a simple observation. When you walk into a space and notice how your footsteps and voice are reflected back to you, the echoes create a subtle sense of awe. According to Attention Restoration Theory, experiences that evoke fascination and effortless engagement can help replenish mental resources. We wanted to explore whether these moments of acoustic interaction between a person and a space could invite gentle attention and, in turn, support cognitive restoration. In Attention Restoration Theory, this is referred to as soft fascination, a type of stimulus that is engaging but not overwhelming.
Exploring Echoes as a Path to Mental Restoration:
During a live demonstration at the MIT Museum, we used auralization a technology that allows you to hear your voice as if you were in a different place using that place’s sound signature or impulse response. A volunteer hummed into the acoustic signature of Hagia Sophia. Later, the entire audience hummed together and reflected on their experiences. The conversation pointed to the potential of such acoustic interaction to support a meditative state by impacting sense of space, time, and self.
This inspired a controlled experiment to study the restorative potential of indoor acoustic environments. We asked people to experience different sound environments (Figure 1) and measure their cognitive activity before and after each interaction. Early results suggest that interactive acoustics may support attention restoration depending on the acoustic characteristics, opening a new way of thinking about how sound affects us indoors.
Figure 1: Virtual interaction with an acoustic environment during the experiment, where a person hears their own voice transformed through the acoustic signature of another space.
Why does this matter?
We spend most of our time indoors, yet discussions of restorative environments often focus on natural settings. This is especially relevant for workplaces and schools, where mental fatigue is common. It may also hold meaningful promise for neurodivergent individuals, including those with ADHD, who often benefit from environments that support attention without overstimulating it.
We imagine applications in immersive restorative spaces where people can interact with sound to reset and return to their activities with greater clarity. We also envision subtle integration into transitional spaces such as staircases, corridors, and building entrances that provide gentle cognitive relief as people move throughout their day.
Sound(e)scape reframes acoustics not as background, but as a tool for well-being. By understanding how interactive sound shapes attention and cognition, we can design buildings that do not simply avoid harmful noise. They can actively help the mind take a restorative break.
Figure 2: Visualization of interacting with different acoustic environments. Left: Max Addae vocalizing in an office environment (MIT Media Lab). Middle: “Hagia Sophia – Muhammad, Allah, Abu Bakr” by Rabe!, licensed under CC BY-SA 3.0 (https://commons.wikimedia.org/wiki/File:Hagia_Sophia_-_Muhammad,_Allah,_Abu_Bakr.jpg) Cropped and one person (Max Addae) added by Alaa Algargoosh. Right: Max Addae vocalizing in Boston Symphony Hall.
Sound recordings:
1. Vocalizing in an office environment (MIT Media Lab). (Voice: Max Addae)
2. Virtual vocalization in Hagia Sophia. (Voice: Max Addae)
3. Virtual vocalization in Boston Symphony Hall. (Voice: Max Addae)
The virtual vocalizations were generated using the impulse responses available at ODEON software library.
