New super imaging tool unveils unprecedented brain tissue resolution

The human brain, with 86 billion neurons, is a remarkable computational marvel. Enter LIONESS, a new tool that reveals its architecture like never before.
Sade Agard
LIONESS can image and reconstruct the sample in a way that clarifies many dynamic structures and functions in live brain tissue
LIONESS can image and reconstruct the sample in a way that clarifies many dynamic structures and functions in live brain tissue

Julia Lyudchik ISTA 

Scientists have developed a new 4D imaging tool that enables analysis of live brain tissue with unprecedented comprehensiveness and spatial resolution, as reported in a study published in Nature Methods on July 10.

The technology holds immense potential to unveil the functional architecture of brain tissue— and possibly other organs— shedding new light on the enigmatic nature of subcellular structures and how they change over time.


Brain tissue is an incredibly intricate subject for scientists to study, given its vast complexity and the wealth of information it contains. With around 86 billion neurons, the human brain is an unparalleled computational marvel. 

However, comprehending this complexity poses a significant challenge, necessitating advanced technologies to unravel the microscopic interactions within the brain. This is where imaging becomes indispensable in the field of neuroscience.

Developed by Johann Danzl's group at ISTA (Institute of Science and Technology, Austria), LIONESS, which stands for Live Information Optimized Nanoscopy Enabling Saturated Segmentation, represents a significant leap in imaging brain activity.

"With LIONESS, for the first time, it is possible to get a comprehensive, dense reconstruction of living brain tissue. By imaging the tissue multiple times, LIONESS allows us to observe and measure the dynamic cellular biology in the brain take its course," said first author Philipp Velicky in a press release

"The output is a reconstructed image of the cellular arrangements in three dimensions, with time making up the fourth dimension, as the sample can be imaged over minutes, hours, or days."

New super imaging tool unveils unprecedented brain tissue resolution
A pipeline to reconstruct live brain tissue. Acquisition of Microscopy with optimized laser focus.

One of LIONESS's strengths lies in its refined optics and two levels of deep learning— an artificial intelligence (AI) technique. 

Using minimal sample information, the first deep learning step fills in additional information on the brain tissue's structure in a process called Image Restoration. This approach achieves a gentle real-time imaging resolution of around 130 nanometers. 

The second deep learning step analyzes the complex imaging data and automates neuronal structure identification.

The tool successfully integrates functional measurements with structural observations by imaging calcium ion fluxes and measuring cellular electrical activity. It also benefited from the information provided by human cerebral organoids— miniature brain models that mimic human brain development. 

As the brain's structure and activity are highly dynamic, with constant changes occurring as it performs and learns new tasks, understanding this 'plasticity' is crucial to unraveling its mysteries.

Brain imaging techniques

Conventional techniques to get reconstructions of brain tissue include electron microscopy. This captures brain tissue at a few nanometers—a millionth of a millimeter—resolution by interacting with electrons. However, a sample must be fixed in one biological state, sectioning. Hence, no dynamic information can be obtained.

Another known technique is light microscopy, which can observe intact tissue without sectioning but lacks resolution for cellular details. 

That said, Super-Resolution Light Microscopy with SUSHI (Super-resolution Shadow Imaging) and STED Stimulated Emission Depletion) microscopy improved resolution but faces challenges due to potential tissue damage from intense light.

This is where LIONESS excels, as it has been designed to operate under "fast and mild" imaging conditions, according to its creators, while preserving the sample's life.