When Bach meets brain scans

24 November 2015

Vincent Cheung (Croucher Scholarship 2015) is working on computational neuroscience at the Max Planck Institute for Human Cognitive and Brain Sciences.

We live surrounded by noise, yet the exact delineation between a cricket’s chirp and a Bach concerto escapes most of us. According to Vincent Cheung, our brains do know the difference, and he is determined to try to understand why music captures our imagination.

As a Croucher scholar at the Max Planck Institute for Human Cognitive and Brain Sciences, Cheung is on a mission to prove that the brain responds to musical patterns in ways similar to embedded structures in language. “Music as a concept—sounds that make sense— is a universal language, affecting our emotions in an abstract, deep way,” he explains.

Following this line of thought, Cheung’s graduate work explores the way the brain processes embedded structures in music, similar to the way language registers. In language, there can be infinitely long sentences and the audience would still recall the main subject and the way subsequent ideas affect it. Ask anyone and they would have a favourite song, a piece reminiscent of something, or a soothing selection for studying, giving rise to the question of whether people pick up on some patterns similar to language. The pattern in question is a typical feature in Western classical music, in which any piece starts and ends in the same key. Previous research has shown that regardless of musical understanding, electrical activity in the brain as measured by an electroencephalogram (EEG) shows a marked difference if the music deviates from this pattern, though it might not be consciously recognised. Musicians in the 20th century also experimented with the idea of whether symmetry could be heard, writing atonal music based on the principle that it should look good on paper as well as to the ear. “There are important questions in the music-language connection: music is very subjective and it’s difficult to condition or quantify, so the results should give a tangible idea on how the brain processes it,” Cheung explains.

Cheung’s approach will contrast brain scans to determine if there is a registered difference between responses to musical pieces that follow a certain symmetrical pattern and pieces that do not. Functional magnetic resonance imaging (fMRIs) measures brain activity by mapping changes of blood flow in different brain regions, and will enable Cheung to see which areas of the brain are engaged in responding to the music. “This experiment is based on the artificial grammar learning paradigm, which is like trying to learn an alien language without anyone telling you how it works,” he explains. “In theory, your brain will decide if it’s correct or not.” Studies regarding language have shown that Broca’s area in the frontal lobe, a hub of syntactical structures, is key to recognising embedded structures and linguistic patterns, and Cheung hypothesises that this area will also be a key player in his study. The task at hand is groundbreaking, as scientists have previously only mapped responses to language and not music, for which the duration of exposure could be longer. “I scanned myself a few weeks ago, and it was incredible to see my brain responding to my own experiment and be part of the scientific record,” Cheung rhapsodises—academically, of course.

While music has been a constant since childhood, including playing in orchestras, Cheung describes his academic leanings from wanting to be an engineer to studying math until his third year at university, when he took a course on theoretical neuroscience. Finding a unique way of applying his mathematical skills to something new, the addition of music followed swiftly. “To me, an engineer is essentially someone who builds on existing materials to tackle new problems and applications,” he explains. “We don’t think much about how important music is to our lives, but it’s all around us, and it’s a power we should harness, not unlike solar energy. We need to take more risks and collaborate across fields to make worthwhile progress.”

Understanding the emotions evoked by music can and should be understood, beyond questions of what makes it sound so good or how it makes people feel certain ways. We’re told to play classical music to babies, while we study, and to relax. Music therapy has shown promise in communicating with patients with severe disabilities or trauma. Cheung notes that while there has been considerable psychological research on how people process sound and music, imaging researching that shows what goes on in the brain is needed to better utilise and understand the medium. This would the next step of his research. Beethoven naturally enters the conversation; his ability to express poignant emotion into stirring composition despite severe hearing limitations, whose music is deeply intertwined with events such as the demolition of the Berlin Wall. “The mechanics of it is beautiful,” Cheung enthuses, “It’s an incredible chance to utilise scientific imaging to approach music from an aesthetic point of view, to study appreciation, identify perfect composition, why different musicians play the same piece differently. It’s like splitting the atom, in a way, trying to define that creative spark.”

Vincent Cheung was awarded a Croucher honorary scholarship in 2015 in support of his graduate studies at the Max Planck Institute for Human Cognitive and Brain Sciences. He received his undergraduate degree in Mathematics from the University of Warwick, and is currently finishing his MSc in Computational Neuroscience at the Bernstein Centre for Computational Neuroscience in Berlin, Germany.

To view Vincent Cheung's personal Croucher profile, please click here