About me

I am a computational neuroscientist working on building a model of the brain. My aim is to understand the brain by building it. I use biophysical circuit models to simulate neuroimaging data, investigate the simulated brain signals using dynamical systems theory, and compare the model parameters to biological features to see how well the model captures the biology.

My working hypothesis is that the brain is a hierarchically organized complex system. The idea is described vividly in Herbert Simon's seminal essay, “The Architecture of Complexity” (1962). Simon wrote that “in the face of complexity, an in-principle reductionist may be at the same time a pragmatic holist.” Neurons and synapses are real, and yet the brain is best understood at the level of the whole. He went on to name the form that this organization most often takes:“Hierarchy, I shall argue, is one of the central structural schemes that the architect of complexity uses.” That is why I study hierarchy over its alternatives, whether a heterarchy with no fixed ranking among regions or a parallel distributed system with no ranking at all, and why I build my circuit models at the scale of the whole brain.

There are many forms of hierarchy (see Hilgetag and Goulas, 2020, a very nice review of the types of hierarchies in the brain). For a complex system that needs regulation and information processing, the most important aspect of hierarchy in the brain is how information flows between brain regions. This form of hierarchy has traditionally been studied in animals with invasive tools, such as injecting a virus into a living brain and letting it spread throughout the brain. Thus, in humans, the hierarchical organization has long been conjectured but never formally shown. In my PhD I showed that a cortical hierarchy can be recovered non-invasively from fMRI. This hierarchy is the ordering of brain regions by the net influence between them, hence the term “signal-flow hierarchy.”

My current work focuses on how this hierarchy enables flexible computation in the brain. One may investigate this at the synapse level, since synapses can be modulated at the speed of thought. However, the overall scaffold of the brain that connects the regions, allowing global communication and coordination (which is what I hypothesize to underlie cognition), cannot change that fast. It changes over days and months, and stays quite stable once a human becomes an adult. My hypothesis is that the signal-flow hierarchy provides different routes for signals to travel along (owing to the different types of projections across the hierarchy), and that neuromodulation of brain regions along the hierarchy sets which routes are on and off.

To learn more about my research, the Research page tells the longer story.

Current position and background

• Postdoctoral researcher, Combine Lab (PI Seok-Jun Hong), Center for Neuroscience Imaging Research, Institute for Basic Science, and Sungkyunkwan University, Suwon, South Korea
• I completed my PhD in biomedical engineering at Sungkyunkwan University in 2026, supervised by Seok-Jun Hong. Before that I trained in neuroscience at the University of Bonn and in biology at Chungnam National University.

Research interests

• Hierarchical organization of the brain
• Neuromodulation for adaptive processing
• Biophysical whole-brain modeling
• Neuroanatomy across species
• Artificial intelligence and cybernetics

News

• September 2026My paper on the state-dependent signal flow hierarchy of the human cortex is out in Nature Neuroscience. Read
• August 2026My paper on life-inspired interoceptive AI is out in Nature Machine Intelligence. Read
• August 2026PhD awarded. I represented the doctoral graduates of science and engineering at the commencement, and continue in the Combine Lab as a postdoctoral researcher from September.
• May 2025My abstract “Intrinsic effective connectivity as the basis of functional specialization” received a Merit Abstract Award from the Organization for Human Brain Mapping. I presented it as a talk at OHBM 2025 in Brisbane in June. Watch

Selected publications

All publications