Dr. Kerry Walker
University Research Lecturer Department of Physiology, Anatomy and Genetics, University of Oxford
Postdoctoral Research Scientist Department of Physiology, Anatomy and Genetics, University of Oxford
PhD in Physiology University of Oxford
Dr. Kerry Walker had never met a real scientist when she was a young child, and she thought they might be make-believe, like leprechauns. Finding herself in foster care at the age of 4, and being raised in a low-income family, there seemed little chance of even going to university. But hard work throughout school led to a full university scholarship, opening up possibilities she had hardly dared to dream of before. After her first year as an undergraduate student, she worked as a summer research assistant in the lab of Prof. Gerard Martin and Dr Darlene Skinner, a neuroscience lab focused on spatial learning in rodents. This eye-opening experience made her realize that science was a real job – moreover, her dream job. She enjoyed the discovery of experimental work so much that she abandoned her original plan of becoming a medical doctor and began her career as a neuroscientist.
After her B.Sc. in Behavioral Neuroscience at the Memorial University of Newfoundland (Canada), Kerry continued her training in a Neuroscience M.Sc. program at Dalhousie University (Canada), where she worked in Prof. Dennis Phillips’ lab, studying perceptual correlates of language and reading development. During that time, Kerry became interested in understanding auditory processing at a more cellular level. This led her to join the lab of Prof. Andy King and Dr Jan Schnupp (Department of Physiology, Anatomy and Genetics, University of Oxford) to pursue a PhD in Physiology. Her doctoral research combined ferret behavior and electrophysiological techniques, investigating how neuronal activity in the auditory cortex relates to the processing of natural sounds.
By the end of her PhD, Kerry had helped develop recordings of neuronal activity in awake, behaving ferrets in the lab; an innovative step that would allow her to further her research into auditory processing. To fully exploit her achievement, she took an unconventional route for her postdoc by deciding to stay in the King lab. She used her newly established technique to investigate pitch perception. Pitch is a key feature in auditory processing that allows us to recognize the same melody if someone plays the same song on a violin or on a piano. Her postdoc work helped reveal the neural correlates underlying this perceptual constancy in the auditory cortex.
Kerry’s first step toward establishing her independence was receiving an Early Career Research Fellowship at the University of Oxford. Achieving independence is a challenge in normal circumstances, but Kerry strived to do this in the same department in which she did her PhD and postdoc. She describes the step to independence as daunting; “You don’t have your PI to fall back on, it’s really on you […] The hardest part is coming up with your own ideas and believing in them”. To differentiate her research from that of her mentor, Kerry pursued an assortment of strategies. She established collaborations with different universities and departments, endeavoring to think outside the box of her previous work. Leveraging her proven resourcefulness, she again developed a new technique: her lab was the first to adapt two-photon calcium imaging to study ferret auditory cortex. With their gyrencephalic (i.e. convoluted) cortex and their hearing range that is highly overlapping with human hearing, ferrets are well established models in auditory neuroscience and are often preferred to rodents.
Today, Kerry’s research combines cutting-edge techniques to study how neurons encode different sounds in the ferret auditory cortex. She relies on two-photon calcium imaging and Neuropixels probes, next-generation electrodes that enable the recording of hundreds of neurons across the depth of the cortex. Employing two different techniques allows Kerry to combine their complementary strengths—cell- type specificity, afforded by expressing calcium indicators in the neuronal subtypes of interest, together with high temporal resolution and access to different cortical layers, provided by Neuropixels probes. Kerry is using this arsenal of tools to better understand auditory processing, including phenomena such as frequency tuning, pitch perception, and reverberation compensation.
Having given birth to her daughter while establishing her lab, and at the same time that her first PhD student was writing up her dissertation, Kerry is open about the struggles of being torn between family and lab life. Like many scientists, she experiences a constant dissonance of thoughts—the pull of being with family while she works in the lab, or the push to be in the lab while she spends time with family. “It’s something you have to learn to deal with, because you’ll never be a perfect mother and you’ll never be a perfect scientist, so you just try your best”, reflects Kerry. Beyond family life, accepting that perfection is impossible has been a precious pearl of advice in Kerry’s career, reminding her not to hold back, but to keep moving forward, constantly pushing the boundaries of her techniques and ideas.
When she is not in the lab, Kerry spends most of her free time with her husband and daughter. As the first member of her family to attend university, Kerry now wants to be a role model for her daughter and other people from disadvantaged backgrounds, hoping to inspire them to pursue their goals and break social barriers. Science is a real job after all, and Kerry is living proof.
Find out more about Kerry’s exciting research and about her lab here…
…and check out Cristiana’s full interview with Kerry on January 10th, 2020 below!
