My Journey in Neuroscience
For two decades, I’ve been exploring the human mind and brain, through observation, study, hands-on research, and guidance from leading experts. What began as curiosity has grown into a lifelong, evolving journey of learning and discovery.
The early years
Understanding grandma’s memory loss
My fascination of the human brain started during high school (2005-2006). I’ve always been curious about people and why they do what they do. So when I learned about the brain in biology class, I was hooked. As a result, I decided to write my final assignment on what happens in the brain when people develop Alzheimer’s Disease, which is what my grandmother was suffering from at the time. I reached out to the Donders Institute in Nijmegen in the Netherlands in search for an expert to interview. A reputable geriatrician, Prof. Olde Rikkert, generously took time to talk to me. Little did I know that I would end up doing actual science with him many years later (Olde Rikkert et al. 2011).
Studying neuroscienCe
From Psychobiology to Cognitive Neuroscience
Only one bachelor programme in the Netherlands truly satisfied my intellectual interests: to understand how our brain gives rise to behaviour. My decision to study Psychobiology at University of Amsterdam (2006-2009) was easily made. Three years later, I graduated cum laude with a thesis on motor imagery (i.e. mental rotation of hands), written at the Donders Centre for Cognition in Nijmegen (in part published in ter Horst et al. 2012).
My work was a stepping stone to the research master in Cognitive Neuroscience at Radboud University (2009-2011). To explore the field of systems neuroscience, I investigated how the rat’s brain processes sensory input under different states (anesthesia vs. awake) as part of my thesis and graduated again cum laude (Janssen 2012, Proceedings of the Masters Programme CNS, p. 18).
Becoming a scholar
Bad habits and how to break them
In 2012, I seamlessly transitioned from my project as a research assistant into my doctoral studies at the Donders Centre for Cognitive Neuroimaging (2012-2017). My work focused on behavioural control in health and disease (Janssen 2017).
I first investigated the role of dopamine in behavioural (in)flexibility in gambling addiction (Janssen*, Sescousse* et al. 2015, Sescousse et al. 2016, van Holst*, Sescousse* et al. 2018, Sescousse et al. 2018, Ojala et al. 2018). Subsequently, my focus moved to the fascinating domain of eating behaviour, with which many people struggle to very different degrees. I investigated the neurocognitive mechanisms that may explain why some people are better at resisting delicious temptations than others, for example related to attention, reward processing, reinforcement learning, and decision making (Janssen et al. 2017). The same people were invited to take part in a tailored 8-week intervention programme, either mindful eating or an active control, to test their effect on our neurocognitive measures (Janssen et al. 2018, Janssen*, Duif* et al. 2023). Mindfulness practice is thought to help regaining control over our autopilot and reducing reactivity.
Refining my research ideas
Habits: brain, body, and environment
To continue my work on dopamine and people’s eating behaviour, I started a new chapter in Leipzig, Germany. At the MPI for Human Cognitive and Brain Sciences and in collaboration with Leipzig University Medical Centre, I investigated the role of dopamine in obesity (Janssen et al. 2019, Morys et al. 2020, Janssen et al. 2020, Janssen & Horstmann 2022, Herzog et al. 2024a, 2024b) and in relation to a diet high in fat and sugar (2017-2021) (Hartmann*, Pauli* et al. 2020, Hartmann et al. 2023, OSF project). Here, the interaction of the brain with the body and its environment became increasingly important.
My desire to understand people’s (in)ability to adjust to changes in or around them then brought me to the Neuropsychology department of Prof. Markus Ullsperger at Otto-von-Guericke University Magdeburg (2021-2024). Back to the basics, with the ultimate aim to understand real-world habits and (in)adaptive behaviour in all their diversity.
I continued my work on reinforcement learning, working memory, and decision making in changing environments in people with no excessive (eating) behaviour (Herzog et al. 2025, OSF project and preregistrations). At the same time, I’ve been refining my research ideas, diving deep into the mechanisms underlying habits (PuG symposium 2024) in collaboration with experts in the fields of habit learning and computational neuroscience.
I’m currently working as a postdoc at Otto-von-Guericke University Magdeburg, Leipzig University Medical Centre and the MPI for Human Cognitive and Brain Sciences in Leipzig.
to be continued…
My work on