In this presentation I will demonstrate the benefit of modern optical techniques especially for neuroscience: After an introduction to STED microscopy the first part will present how Fast STED microscopy deciphers neurotransmitter-vesicle motion. Furthermore, it will be shown how integrating phase contrast into a STED microscope provides a second, label-free contrast channel. This allows for easy correlation of morphological structures with high-resolution fluorescence images. It is demonstrated that Spiral Phase Contrast in scanning confocal configuration yields improved optical contrast and allows quantitative phase measurements.

The last part will present microscopy in an unusual model system, turtles. Reptilian cerebral cortex contains 3 layers, similar to hippocampal and piriform cortices of mammals. Turtle cortex offers experimental advantages: it is resistant to anoxia and operates at room temperature. Cortical slabs can be cut in orientations that minimize lesions and keep inter-neuronal connections intact. The entire brain can even be extracted and kept in vitro for several days. Dendritic spines and calcium signaling can be advantageously studied in these preparations.