Since 2018, you hold a FNRS Research Associate (Chercheuse Qualifiée) position, and lead the Physiology of Cognition Lab, at the GIGA of the University of Liège. Your research in cognitive and clinical neuroscience yields unique insights into the normal and altered states of the human mind. Can you tell us more about your research questions, and your methodological approach?
As a psychologist by primary training, I carry a deep intertest in how people think and experience life. I find it fascinating listening to people unravelling their train of thought and observe how they behave.
Early on in my training, this interest came together under the umbrella of consciousness studies, which I initially approached via the lens of philosophy.
Later on, during my Master’s degree, I had the chance to see how fragile human consciousness can get in certain neurological conditions. For example, I had been in contact with stroke patients who had lost their ability to coordinate simple daily tasks, without them realizing that they were making mistakes (aka anosagnosia). This lack of awareness was so enigmatic to me in so many levels.
This is when I decided to dive deeper into the clinical, mechanistic, and theoretical understanding of conscious and unconscious thought by pursuing doctoral studies, brining me to ULiège in 2007. It was during this period that I got trained on biomedical imaging, which essentially gave me the chance to investigate thinking from within, directly from brain activity.
Also, during my postdoc time at the Paris Brain Institute, the studies we conducted with patients who found themselves in post-comatose states, totally unable to communicate, taught me that human consciousness certainly holds its mysteries. Yet, it is not inaccessible.
Since my appointment as a FNRS Research Associate in 2018 with my team we investigate how the human mind can be measured in an objective way by means of functional brain imaging, electroencephalography, and peripheral physiology. My question is not so much to answer why we are consious at all. As a curious and pragmatic person, I am rather intrigued to rather showcase how we are conscious and what happens when this ability seems to elapse. Essentially, my research questions circle around what consciousness and unconsciousness does.
Although we experience it daily, little is known about mind blanking. Your team is a pioneer on this research topic. So, what happens in the brain during mind blanking? Does mind blanking serve any function?
By and large, mind blanking refers to moments when we estimate that we think of nothing in particular, that nothing is crossing our minds, that thoughts are missing.
This mental state is so counter-intuitive, yet so real for some, simply because we have the impression that our waking life is constantly thought-full. Surely, our train of thought seems to be occupied by mental content that is eidetic, semantic, with narration, inner speech, singing, to name some. So vibrant.
How can it be that there are blanks to this stream? It’s indeed fascinating to see that, when people have the chance to report mental blanks, they do so. In other words, it can be possible that moments of unconsciousness can take place when we are awake. This is exactly what we see with brain imaging.
Using fMRI, for example, we were able to show that our brain activity during reports of mind blanking is organized in a way that all brain regions communicate with each other and in the same manner. That is, neural activity is at its lowest and this concerns most regions of the brain. As if our brains momentarily go into sleep mode.
Yet, I feel that when it comes to mind blanking, we are still in uncharted waters.
Based on when people report having blanks, it may even be that different forms of mind blanking exist. For instance, when we experience racing thoughts, we can hardly differentiate the exact thought content.
But why we get to report mind blanking in the first place? This is a very important question to me as I estimate it has to do with brain health. We have just started to experimentally investigate the possibility that, during mind blanks, our brain’s “cleansing system” is taking action to remove neuronal by-products. This activity driven by the so-called glymphatic system, is primarily active during sleep, and has been linked to Alzheimer’s Disease when not functioning properly.
My objective is to provide evidence that such neurotoxic clearance also happens, discretely, during wakefulness, which, when captured by our attention, it is explained away as mind blanking.
I feel that such a mechanistic perspective opens new paths to the understating of the clinical and social implications of spontaneous thinking, and can be of interest to policy makers that promote brain health altogether.
Can your research on human consciousness inform about the level of consciousness in other animal species?
For the moment I can talk about the inverse. When it comes to studying brain function via the functional connectivity paradigm, we can get important insights from to how brain activity configures in different species.
For example, past work of ours on dynamic functional connectivity was inspired by what was conducted on non-human primates, awake and anesthetized. Studies from rodents also helped us gain a general understanding in how brain activity configures under anesthesia.
Certainly, there are major differences in the way we humans function, but the commonalities in brain modes, to me, underlie that we are part of nature’s bigger picture, than a biological exception of it.
Now, whether consciousness follows similar principles across species remains to be better clarified. Although we seem to communicate our minds in a different way, yet we don’t have good reasons to believe that consciousness is a matter of humans only.
Your research examined the consciousness state of behaviorally unresponsive patients (e.g., comatose, locked-in syndrome patients). Might your research shape the development of new practices in the clinical setting?
Although I have moved on from the study of disorders of consciousness, I remain intrigued by how we still need to find ways which would indicate that people retain some sort of consciousness, even if they cannot communicate.
To that point, my current research has adopted an embodied perspective, where we argue that bodily signals carry complementary information about consciousness and cognition. Next to brain activity, we now consistently measure peripheral physiological signals, like cardiac activity, respiration, muscle tension, and electrooculography to see how brain and body are aligned, or not, in different mental and consious states.
We have shown, for instance, that during sleep, cardiac activity slows down when people are exposed to relaxing words, but not to the reversed version of the same words. This implies that we are still anchored to our environment, even if we cannot consciously perceive it or interact with it.
Such information about brain-body interactions I feel can be valuable to infer how the mind works when behavior is at its minimal.
You are trained as a Gestalt psychotherapist. Has this clinical expertise contributed to the development of your research?
My training as a psychotherapist was rather a forced choice at the time-- although I now perceive it as a parallel destiny. In fact, after a failed first attempt to secure tenure, I realized that my options were not many. Indeed, getting a PhD can make you an expert in such a small niche of a field that you may only wonder what you are capable of out in the “real world”. The following year not only found me with tenure and psychotherapy training, but also with a new baby. Hands were literally full. Yet, I decided to complete the training, as I was seeing that my understanding of human experience was getting more global.
By listening to people unravelling their experiences and by investigating what happens at the moment, mentally and physically, inspired me to get new questions asked. How can we use our experiences themselves to shape up our brains and bodies? How crystallized belief systems can lead to mental blanks and hinter brain dynamics? How, when being fully present in the moment can lead to lower stress responses? These are some of the ongoing questions that discretely pertain my research.
At a broader sense of doing research, psychotherapy training has definitely helped my communication skills and presence with colleagues and trainees. It’s my conviction that science, as a social construct, only benefits from inclusivity and the so-called soft skills seem to be the hardest of all. In that sense, I am convinced that principal investigators ought to get their communication dexterities sharpened in, for the sake of not only professional prosperity, but work-life balance, as well. We only learn with others.
Where is your field heading to in the future? Are there initiatives that you are particularly excited about?
I feel that I am getting close and closer to the notion of brain health. I am intrigued to study the intersection between human behavior, brain function, and general health status. Essentially, by getting new insights how all these levels are inter-connected, I am curious to see whether there can be universal patterns or idiosyncratic fingerprints to how we respond to mental, environmental, and biological probing.
Could you tell us more about your trajectory? What attracted you to the University of Liège, all the way from Thessaloniki, Greece?
As many great things in life happen unexpectedly, I’d rather say that my arrival in Liège was more incidental than intentional. I had just finished my Research Master’s in Neuropsychology, Psychopathology and Cognitive Neuroscience at University of Maastricht, and I was looking for a PhD position around the region.
In that sense, it was rather The Netherlands that brought me across the border from Greece, where I had just finished my basic degree in Psychology at the Aristotle University of Thessaloniki. While in Maastricht, then, and during my online search for a doctoral program, I came across an open call as Marie Curie fellow at ULiège, which was dedicated to the study of post-comatose disorders of consciousness led by Prof. Laureys. I got fascinated by this topic and I applied immediately. That brought me to the Cyclotron Research Center and the CHU Neurology Department and the rest is history.
My academic interest in consciousness science met the clinical perspective and gave me a new view about how this field of research pertains to so many aspects of human life that we typically take for granted.
Your scientific excellence and success are impressive: your work has been published in high-impact journals and is highly cited. It has been featured in the National Georgraphic's Special Issue "The Brain" (2022). Your team has received prestigious grants and awards. What assets supported you in this odyssey? In your opinion, what should early-career researchers pay particular attention to fuel their scientific development?
Thank you! Without much thinking, I can attest that this type of recognition is a mixture between being intrinsically driven to find answers to flaming questions, having equally motivated colleagues that push things forward with you, and a bit of luck to have interested stakeholders that recognize that, indeed, what we do is of value.
I feel that the most important ingredient of all is to be burning to discover that piece of the puzzle that is currently missing from the bigger picture. Which leads to the next, and the next. And new knowledge is created every time.
Such a creative process. And as such, it comes with impasses, but also perks when recognition comes. One thing I would advise to early-career researchers, then, is to keep fostering their “why”. Once curiosity stays on the table, all what follows will be naturally ignited: funding will be obtained, data will be collected, data will be analysed (again and again), and new knowledge will emerge.
And I could not advise more the need of open science practices. Pre-register the hypotheses. In other words, bet against yourself and let the data inform your initial intuition.
Be prepared having made an inapt prediction, this by itself means something. Stay challenged and don’t take things personally, because, it’s not about you. It’s about the process of creating something new. And, like in many cases in history of science, many pioneers had to be proven wrong to get things right.
