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Optical Imaging of Neural Activity


Calcium Reporters Reveal Neuronal Activity

We use calcium imaging to explore the spatial dimension of neural processing in auditory and antennal interneurons, in afferents and in motor neurons. These cannot be revealed with single cell intracellular recordings. Local changes in calcium signals in dendrites and axons demonstrate the site of neural activation in single neurons and also the site of processing in neuronal networks and populations. We inject calcium reporters into neurons with microelectrodes and recently developed a method that allows electrophoretic delivery of calcium reporters into neurons through the sheath surrounding the nervous system. We are now in the process to develop and apply this method to different systems.

Cricket ON1 neuron (left) and its optical calcium signal during acoustic stimulation (right)

Watch and listen to the cricket Omega Neuron ON1 responding to sound stimuli, while changes in its cytosolic calcium signals are imaged: hear the neuron’s spike pattern and observe the changes in the optical calcium signal in dendrites and the axon.


Insect neurons are not only activated by the communication signals, but they will also respond to acoustic signals like music. Here the cricket has been exposed to the "Carmina Burana" and "Bolero", see how it responds.

Besides this the Omega Neuron also responds to funky pop:


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