Postdoc fellow tuning in to rhythmic patterns in brain, music

March 09, 2017

Western postdoctoral fellow Molly Henry

Story and photo by Paul Mayne, Western News

When you’re speaking with Molly Henry, she’s taking note of the rhythms in the conversation you are having.

Henry, a postdoctoral fellow at Western’s Brain and Mind Institute (BMI), is interested in how synchronization between brain rhythms and environmental rhythms – for example, musical rhythm ­– shapes auditory perception.

“I look at how your brain waves synchronize to rhythms. I like to think about the rhythms in everything,” she said. “My speaking voice, for example, has rhythms and there are some fluctuations with loudness and pitch, and your brain synchronizes to those patterns. And, in conversation, we’re taking turns and somehow able to do this without thinking too much. So, what is this? What is it doing for us?”

Henry’s work was recently recognized by the Association for Psychological Science with a Rising Star designation, which identifies outstanding psychological scientists in the earliest stages of their research career post-PhD whose innovative work has already advanced the field and signals great potential for their continued contributions.

She is particularly interested in whether, and how, synchronization of brain rhythms with musical rhythms gives rise to the perception of a ‘beat.’ In the long run, Henry, who works in Western Psychology professor Jessica Grahn’s Music and Neuroscience Lab at the BMI, wants to know how individual differences in brain/environment synchronization might lead to impairments that accompany aging or disordered states.

“When you listen to music you want to move your body – that’s a natural thing,” said Henry, who spent a few years at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany before coming to Western in 2015.

When music is played for someone in a scanner, for example, their brain becomes active to the sounds while actually not moving to the music. It’s actually preparing you to move, she added.

“The important link is the movement. Someone with Parkinson’s disease will lose some of their abilities to do things related to rhythm and beat, so simple laboratory rhythms become harder to discriminate. But flip on music, in some cases, and they can move,” said Henry. “If this music-brain-movement link depends on parts of the brain that sometimes change in association with a particular disorder, can we capitalize on this relationship in a non-medicine or non-chemical way?”

“She has been a real force both in the Grahn lab and in the BMI in general,” said BMI Director Mel Goodale of Henry’s success. “Her work on rhythmic activity in the brain is not only revealing how incoming information, particularly music, is encoded in the brain, but is providing new directions for understanding and diagnosing a range of brain disorders.”

Henry has also taken a more active role within the BMI community, added Goodale, both as an architect of a new funding program for collaborative work between postdocs working in different labs in the institute and, on a lighter note, as a singer in the BMI house band, the Untidy Naked Dilemma.

One thing in common between music and speech, or any kind of rhythm, Henry noted, is brain waves become synchronized to rhythms, which helps you perceive and understand them. These brain rhythms are parts of the brain going back and forth between being ready, and not ready, to receive information.

“It’s easier not to have your neurons at the ready all the time. The natural state is going back and forth – ready to fire, not ready to fire,” said Henry. “If you can line up those fluctuations with a rhythm, when the important stuff is happening, and you can line up your ready time and line up the resting time, when times it is silent, it’s a way for you to process information. There are lots of disorder situations where our brain rhythms get interrupted and affect the way we perceive the world.”

The ability to synchronize our brain waves also helps us separate the important things from the background noise, added Henry. Older adults have difficulty doing this. Is it related to our brain not synchronizing, Henry wondered.

Coming to Western has given Henry a unique opportunity to bring together her expertise in analysis of brain signals with her interests in rhythm and music perception.

“Brains are complex. You can’t just do one experiment, say, ‘Here is my result and now I understand how the brain works,’” she said. “We’ll never run out of questions. I like adventures, generally, so I think not knowing is fun, actually.”