2-Photon calcium imaging
We are using 2-photon fluorescence microscopy in vivo to record neuronal network activity following sensory stimulation. During the experiment, the cell-specific expression of fluorescent proteins allows to identify different cell types, e.g. inhibitory and excitatory neurons (see figure). Individual cells often respond specifically to certain stimulus properties, e.g. the orientation of the gratings presented.
![](/bioimaging_media/Bilder/2_photon+setup-font-7-height-332-width-480-p-78.jpg)
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Figure: Left: Schematic drawing of experimental setup. During sensory stimulation with moving gratings neuronal network activity is recorded using 2-photon microscopy and fluorescent indicator dyes. Right: Response pattern of an excitatory neuron (red 1) and of an inhibitory neuron (blue 2) is displayed (A). The excitatory neuron responded specifically to the orientation of the grating, whereas the inhibitory neuron responded unspecifically (B).
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