23. May 2023

Johann G. Danzl: Untangling brain tissue architecture with light microscopy

Exner Lectures 2023 – Johann Georg Danzl (Institute of Science and Technology Austria)

The incredibly complex arrangement of nerve cells in brain tissue and the transmission of information between them at synapses form the basis of the brain’s information processing network, made up of ~86 billion neurons in human brain, each with thousands of synaptic connections.

Light microscopy holds tremendous promise for unraveling how the brain’s function interrelates with its cellular architecture, as it can visualize the molecular machineries at work and even allows observation of living biological specimens and their activity. However, its resolution is limited by diffraction of light waves to a few hundred nanometers, which is far too coarse grained to tell the densely spaced cellular structures in brain tissue apart. Even with super-resolution optical imaging, which offers resolution much better and reaches into the nanometer regime, reconstructing the cellular architecture of brain tissue has been out of reach.

I will discuss the novel technologies we develop to overcome current limitations in resolution, contrast, and labelling to visualize the cellular make up of brain tissue down to the level of individual synapses, and how we do so in the living system and across the different scales of organization. For this, we pursue a genuinely interdisciplinary approach, integrating optical developments, advanced sample preparation, and deep-learning based image analysis to ultimately enable new discoveries about how the brain works and how its structure evolves over time.