The Color of Sound and the Harmony of Science: An Interview with Öğütnaz Çoban

First of all, hello — it's a real pleasure for me to be on this lovely platform. I was still in high school when I first heard of audiology. The idea of working on the physics of sound, acoustics, and the physiology and anatomy of hearing seemed very interesting to me even then. But before starting my undergraduate degree, I had it in mind to definitely add another field alongside it; because I thought that audiology — an already very broad discipline on its own — was a field in which one needs to specialize.

These thoughts became clearer thanks to my internships during my undergraduate studies. After both my clinical and device-industry internships, I decided not to jump straight into professional life; instead, to pursue a master's degree in this field and to advance academically. During and after my undergraduate studies at Başkent University, I worked for about 6 years as an assistant director at a music school. Because I was so immersed in music, I began researching schools and supervisors.

It was right during this process that I met my current supervisor, Mustafa Yüksel. Working in psychoacoustics, musical perception and cochlear implants, he was an exceptionally well-qualified prospective supervisor for me. About 2 years after graduating, I began my master's degree under his supervision at Ankara Medipol University. We are currently in the thesis phase.

Put simply, auditory gist is a tremendous ability that allows our brain to understand "what a sound is" within milliseconds, without needing to analyze it in detail. Is the sound we hear a violin or a human voice — we decide this within a tiny fraction of a second. This is critical for us to maintain communication in noisy environments, because it relies not only on the frequency of the sound, but on that distinctive color we call "timbre."

Our brain resolves timbre through three basic cues. The first is the Spectral Centroid, that is, the brightness of the sound: an 'S' sound is very bright and sharp, whereas an 'M' sound is more muffled. The second is Log-Attack Time, the sound's 'speed of entry onto the stage': a 'P' or 'T' comes out with a burst, while an 'A' rises much more softly. The third is Spectral Flux, the sound's variability: is it a steady whistle, or ever-changing speech?

In our thesis, we examine how the brain's rapid recognition ability is affected when we play with these brightness, speed and variability settings of the sound, or when we add speech noise in the background. Our aim is to work out which timbral feature is more dominant and how the brain re-evaluates these cues under noise.

Combining laboratory data with real life is the most exciting part of the work. What we focus on in this project is learning users' expectations directly from them, not through indirect means. Because it is not really possible for existing solutions to create the same effect in every user; that's why the goal is for future technologies to be shaped entirely by user feedback.

Among the anticipated innovations, vibrotactile methods stand out, such as wearable devices or special furniture that allow music to be felt through vibration. In addition, special mixing technologies that separate vocals or instruments, and real-time music arrangements, are being worked on. The work is not limited to technology alone; device-specific music programs and personalized rehabilitation training are also among the most important strategies of the future.

Music at home actually works like a natural rehabilitation tool that increases the efficiency and success of the implant.

The musical environment at home directly shapes not only children's taste in music but also their hearing and communication skills. Being exposed in childhood to music at home, to singing together and to social listening activities done as a family, significantly develops the brain's ability to distinguish sounds — that is, auditory discrimination. This in turn contributes to the ability to understand speech in noisy environments, the area they struggle with most as they grow up. In short, music at home works like a natural rehabilitation tool that increases the efficiency of the implant.

This is a project we carry out in collaboration with the dB SPL Speech Perception Lab, and we work with a large population of children/parents. The children we work with receive Western-music-based instrument training; their parents, on the other hand, have not received any music education. Although children in Türkiye receive Western music education, they are unwittingly exposed to many motifs containing makam, such as Turkish pop, the National Anthem and the call to prayer.

We assess pitch and rhythm perception of both Western and Turkish music through consonance/pleasantness and emotional response. Our expectation is that children who receive instrument training will assess consonance with higher accuracy than their parents. Emotional response is a matter of curiosity for all of us: how different will the children's response to Turkish music motifs be compared with their parents? We will find out before long.

The answer to this question is directly connected to the story of how I began my master's degree. I personally experienced and observed how important music education is for the brain from a young age. Music had a special place in every period of my life; I am someone who expresses my emotions through music. This is what pushed me to work in the field of music perception in individuals with hearing loss.

My basic motivation is this: for everyone to be able to enjoy music as much as we do, to make sense of it and to express themselves through it. In some pitch or timbre perception studies I may have a small perceptual advantage; but what truly nourishes my scientific work is the motivation to genuinely improve musical perception in cochlear implant and hearing-impaired individuals by contributing new techniques to the literature.

After my undergraduate studies, I did a clinical internship at the University Hospital of Ferrara (Italy) under the supervision of Prof. Stavros Hatzopoulos. The most obvious difference was the hospital environment: during my internships in Türkiye, there were times we saw an average of 90 patients a day, and 104 on one day. The advantage of this is seeing a great variety of patients and gaining well-rounded clinical experience. In Italy the frequency of seeing patients was low, but the time devoted to a single patient was very long; as an audiologist, detailed guidance could be provided.

I went to Groningen before my thesis period; I worked as an academic researcher at the dB SPL Speech Perception Lab within the UMCG, under the supervision of Dr. Ellie Harding and Prof. Dr. ir. Deniz Başkent. What struck me most was how thoroughly and at length they examine every step of a project. In weekly lab meetings, a team of 15–20 people gave feedback to the presenter even when it wasn't their own field; this increases publication productivity. Because they have to allocate a budget for participants, they place importance on collaboration — although this lengthens the study period, it raises the impact value.

What I'm about to say applies in every field. I decided what to continue with through my internships and the congresses/training I attended; that's why my first piece of advice is for them to take part in all kinds of internships and training. For those who want to advance in a research direction, I argue that choosing a supervisor is more important than choosing a school. First of all, there should be a supervisor from one's own field of interest; communication with the supervisor takes the whole process to a different level.

In the future I want to continue with doctoral and post-doctoral research; I aim to work on psychoacoustics/psycholinguistics, music and cochlear implants. Because technology develops rapidly, I will always be open to new adjacent fields as well.