High-resolution Confocal Imaging

Innovative design has enabled the creation of microscopes small enough to be head-mounted on freely moving animals. These GRIN-lens ‘miniscopes’ monitor calcium signaling of individual neurons in deep regions of the brain. However, miniscopes sacrifice image quality, optical sectioning and multiple fluorescent colors.
Fortunately, data from advanced imaging techniques does not need to be recorded during behavior. By adding a laser scanning confocal microscope, we can supplement the previously recorded data with high-resolution volumetric images of the entire observed brain region. With fluorescent labels and optical sectioning capabilities, specific subsets of neurons can be correlated to the cells active during behavior. In combination with ZEISS Airyscan 2 detection, morphological details of active neurons are resolved, from cell bodies down to individual neuronal processes such as dendritic spines and axonal boutons. Post-collection co-registration of miniscope-acquired data and confocal images results in a richer dataset with wider applications.

Key Learnings:

• Explore the basics of this hybrid imaging approach
• Explain the workflows involved in recording head-fixed data using a ZEISS LSM 980 confocal microscope
• Show multispectral volumetric and functional data recorded using this method