Gallery

This page highlights some work from labs in Switzerland, initially focussing on work in the area of neural reconstruction.  If you would like your lab's work to feature here, please email me mailto:longair@ini.phys.ethz.ch

Kevan A. C. Martin's Lab

This example of combined light microscopy and electron microscopy is the work of Nuno Miguel Maçarico Amorim da Costa, Rita Bopp and Kevan Martin:

This image shows a reconstruction of the dendritic tree of a layer 6 corticothalamic neuron in the cat, created from light microscopy (LM) data.  The red labelling on the tree indicates points where axonal boutons from the dLGN appeared under LM to contact the dendritic tree, while the white dots in the background show all such boutons in the local region.  The enlarged region shows electron microscope (EM) imaging of the location of one of these points of contact, showing that there is indeed a synapse at that point, with the dendritic spine outlined in yellow, the bouton outlined in red, and the blue line indicating the synaptic cleft.  (About 30% of the boutons marked in red actually represent a synapse onto the dendritic tree, as in this example.)  By using this combined EM/LM examination of the tree, the physical dissector method can be used to estimate the number of synapses between axons from the dLGN and layer 6 corticothalamic neurons.

 Hahnloser Lab

A set of distinct brain areas participates in learning and generation of songs in zebra finches. It is known that complex spatio-temporal neural activity patterns underlie vocal production, though the generation of these patterns remains poorly understood. For example, the roles of premotor brain areas RA (robust nucleus of the arcopallium) and HCV (high vocal centre) have been well characterized. However, almost nothing is known about their synaptic organization and the way in which afferent inputs form other brain areas are processed in HVC. The aim of our research is to reconstruct these neural networks using light and electron microscopy. We explore correlative imaging techniques in which we differentially label distinct populations of projection neurons using fluorescent tracers (fig. 1), prepare the brain tissue for electron microscopy and image ultrathin sections with both light and electron microscopes (fig. 2), so that neural structures observed in the electron microscope can be classified using light microscopy data.

Fig 1. Confocal stack projection of HVC region. Neurons are stained using different fluorescent tracers, revealing distinct neuron types.

Fig 2. Overlay of light (red) and electron microscopy images allows for classification of neural processes and synapses.