Dr. Vanessa Stempel
Research Group Leader Max Planck Institute for Brain Reseach, Frankfurt
Postdoctoral Researcher Sainsbury Wellcome Centre UCL, London
PhD Charité-Universitätsmedizin, Berlin
Vanessa Stempel grew up in a household steeped in scientific thought and a fascination with the natural world. Her father holds a PhD in ornithology and her mother studied biology for a few years, but both decided to leave academia. Perhaps unsurprisingly, Vanessa also discovered a passion for biology, particularly zoology and neuroscience, in school. However, she was discouraged from pursuing this burgeoning interest by her parents and teachers on the grounds that she’d never get a job as a biologist. Taking this to heart, Vanessa turned her attention to more creative pursuits. She considered, at various times, becoming a costume designer, then a goldsmith, before eventually deciding to study with the aim of becoming a journalist. These aspirations quickly began to unravel, however, as she realized that to write without having in depth knowledge of any field felt wrong. “To be a science journalist or a political journalist, you need to understand those fields!”, she recalls thinking. It was this sense of disconnect, and a desire to develop a deeper understanding of the world around her, that compelled her to quit her studies and, despite her mentors’ trepidation, revisit her early interest in biology. Though she may not have realized it at the time, this decision would profoundly alter the course of her life and career. Now a principal investigator at the Max Planck Institute in Frankfurt, Vanessa’s research seeks to uncover the neural circuits and cellular mechanisms that govern instinctive behaviors like hunting, mating, and escaping in rodents. In a way, Vanessa’s journey has come full circle, returning her to the wonders of biology that captivated her in her youth.
Vanessa decided to undertake a bachelor’s degree in applied biology with a particular focus on micro- and molecular biology – in what she thought was a rational compromise and heeding early ‘warnings’ against studying zoology or neuroscience. However, she soon realized this field wasn’t for her. Eager to explore basic science research, she enrolled in a research-based biomedical degree at UCL. Choosing the topic of her master’s thesis turned out to be a critical turning point in her academic journey as she found herself torn between neuroscience and infectious diseases. Having arranged a project studying malaria at the London School of Hygiene and Tropical Medicine, Vanessa remembers waking up in the middle of the night thinking “This is a terrible mistake, I need to do neuroscience!”. She canceled this project at the very last minute and instead joined the group of Professors Mark Farrant and Stuart Cull-Candy at the UCL Department of Neuroscience, Physiology and Pharmacology. Here, she embarked on a project studying neuronal ion channels like AMPA and GABA A receptors using patch-clamp recordings and quickly fell head-over-heels in love with electrophysiology. “Watching neurons chattering away in real time blew my mind and made me so happy”, she recalls thinking. Despite this new-found passion, it wasn’t until Mark offered her a place in the lab that she even started to consider applying for a PhD. Although she ultimately decided to go elsewhere for graduate school, Vanessa credits Mark as being one of the first people that believed, and helped her believe, that she was cut out for a career in science.
Keen to pursue her burgeoning interest in synaptic transmission and plasticity, Vanessa moved to Prof. Dietmar Schmitz’ lab in Berlin for her PhD. While she enjoyed the lab environment and got on well with her supervisor, the early years of her PhD were marked by feelings of frustration and countless failed experiments. Vanessa admits grappling with a sense of futility when it seemed that none of her projects were yielding interesting results. Then, serendipity struck. Using patch-clamp recordings to examine afterhyperpolarization (AHP) in hippocampal CA2 neurons – the period after a neuron fires when its membrane potential temporarily dips below its resting potential – Vanessa noticed an odd group of hippocampal neurons that never returned to their resting potential. This chance observation, which Vanessa initially assumed was an artifact, led to a plethora of follow-up experiments investigating what mechanisms could be responsible. Vanessa ultimately found that this sustained AHP in a subset of hippocampal neurons was mediated by cannabinoid 2 receptors (CB2Rs), a receptor commonly found in the peripheral immune system but thought to be absent in neurons of the central nervous system. Vanessa’s work demonstrated that this CB2R-driven hyperpolarization represented a novel and cell-type specific plasticity mechanism that had not previously been identified. Vanessa considers this experience – a chance observation leading to an important result – an excellent example of the huge role luck plays in science. “You can be as competent as you want but science doesn’t always play ball,” she notes.
As she came to the end of her PhD, Vanessa was more convinced than ever that she wanted to stay in science. Reflecting on the questions that interested and excited her, she decided she wanted to pursue a postdoc that would allow her to bridge the gap between in vitro and in vivo work and use circuit-driven approaches to study natural behaviors. She was excited to join the then newly established lab of Prof. Tiago Branco, whom she had met while working as a teaching assistant at the Cold Spring Harbor Laboratory summer school on Ion Channel Physiology. The Branco lab employs behavioral paradigms that use naturalistic auditory and visual stimuli, such as a looming shadow mimicking the appearance of an airborne predator, to study instinctive escape behavior in mice. Bringing a wealth of knowledge and expertise in electrophysiology to the lab, Vanessa set about studying the neural circuits that underlie instinctive escape. Using a combination of behavioral, electrophysiological, and anatomical experiments, Vanessa and her colleagues uncovered key neural circuit and synaptic mechanisms in the mouse midbrain that are critical for making escape decisions. One of the most important things she learned from her time in the Branco lab, other than that it cemented her interest in studying ecologically-relevant natural behaviors, was the power of working as a team and the importance of being aware of your own strengths and weaknesses. As the size and complexity of modern neuroscience projects continues to grow, knowing when to ask for help and tap into the knowledge and skills of the people around you - or with collaborators further afield - is more critical than ever, and much more fun than working alone.
Vanessa admits that, even during most of her postdoc, she never truly believed that she would one day run her own lab. She attributes this feeling to a combination of imposter syndrome, an absence of female professors in her own academic life, and the fact that many of her academic contemporaries were leaving academia altogether. Nonetheless, having just published a big paper and with both she and her partner (also a neuroscientist) starting to think about the next steps in their careers, she realized that now was the time to try. To her astonishment, she was offered the first job she applied to. Now a PI at the Max Planck Institute for Brain Research in Frankfurt, Vanessa’s lab continues to study the neural circuits underlying instinctive behaviors. In particular, her group is interested in two questions. First, to understand how these circuits help the brain resolve sudden motivational conflict: such as when a parenting dam is approached by a predator and has to choose between protecting her pups or fleeing. Second, while behavioral flexibility and the ability to adapt to changing environments is often considered a ‘top-down’, cortically-driven phenomenon, the Stempel lab is hoping to challenge this orthodoxy by exploring how brainstem circuits that underlie instinctive behaviors can promote flexibility in ecologically relevant situations through local plasticity mechanisms.
Looking back on the early days of setting up her lab, Vanessa notes that the transition she found hardest was knowing that other people were now relying on her to succeed. It is now her responsibility to ensure her lab members get the resources, support, and mentorship they need to thrive. Although this took a while to adjust to, she’s come to realize that the impact she can have by enabling others to do good science is much larger than the impact she could have had working by herself. Despite not enjoying the admin part of her job (like probably all PIs), she feels incredibly privileged to have been given the chance to run her own research group and wouldn’t want it any other way. Although Vanessa’s route to neuroscience may have been somewhat circuitous and at times immensely challenging, her journey is nonetheless a powerful reminder that there is no one path to success. Stay curious, find what you love, and don’t be afraid to try something new – you’ll find your place in the end.
Find out more about Vanessa and her lab’s research here.
Listen to Margarida’s full interview with Vanessa on October 6, 2023 below!
