Neurescence’s flagship product – The Chromatone^TM system – provides a powerful integrated approach to observe, manipulate, and dissect a spectrum of neuronal subtypes in multiple brain/spinal cord regions, with single cell resolution. This three-pronged strategy to observe and stimulate activity in defined neuronal subpopulations, while examining behavioral paradigms will reveal accurate underlying mechanisms of physiology and behaviour in awake, freely behaving animals. 

The Chromatone^TM system is the only complete solution for in vivo calcium imaging and optogenetics, that enables simultaneous multicolor imaging and multi-opsin stimulation in up to four brain or spinal cord areas in freely behaving animals.

Services included:

• Hands-on-surgical training
• Neuronal trace extraction support
• Device synchronization with other behavior equipment

The components include the main microscope body, four illumination cubes, control electronics, multimode fibres and imaging fibre bundles. The microscope body is small and light weight, to ensure ease of use during a wide array of behavior paradigms and it integrates cell-type specific calcium imaging and optogenetics.

The illumination cubes contain excitation light sources and optical filters to ensure the correct illumination color arrives at the brain tissue. Active temperature control in the illumination cubes ensures highly stable illumination levels at the brain tissue, throughout a behavior session.

Each illumination cube connects to the microscope body through a multimode fiber and emits three illumination colors:  

• 470nm +/- 12nm for Green Fluorescent Protein Imaging /ChannelRhodopsin optogenetics 
• 550nm +/-7.5nm for Red Fluorescent Protein imaging 
• 632nm +/- 14nm for ChrimsonR Optogenetics

Light from each illumination cube is coupled into an imaging fiber bundle, which carries the light to implanted GRIN lens connectors and then to the brain tissue.

Video 1: GFP imaging ChrismsonR stimulation;
Video 2:  GFP & RFP imaging ChrismsonR stimulation;
Video 3: RFP imaging ChannelRhodopsin stimulation;
Video 4: RFP imaging ChrimsonR stimulation

There are four such imaging fiber bundles, enabling simultaneous multicolor calcium imaging and multi opsin stimulation in up to four brain or spinal cord areas. 

Pictured above is a depicted behavior session using the Chromatone^TM system. 

During an imaging -behavior session, the imaging fibre bundles of the Chromatone^TM are connected to the implanted lens-connectors. Three different illumination colors are available in each implanted region, to enable multicolor imaging (GFP and/or RFP) and multi-opsin optogenetics (ChannelRhodopsin / ChrimsonR). The three illumination colors red, blue and green in each implanted region can be independently controlled using the software.

Pictured below is a lens-connector next to an American dime for size comparison.

Chromatone^TM uses FOUR highly flexible optical imaging fiber bundles. Each bundle includes 18000 single fibers, 7.5micron diameter each. The imaging fiber bundle enables the implanted lens-connectors to transmit fluorescence signal from neurons to the microscope. Pictured below is a GCaMP tagged brain slice, imaged using the Neurescence Multiscopes^TM.

For each imaging session, imaging fibre bundles are connected to the implanted lenses, which transfer images from the tissue to the microscope. The user is required to set the best focus, for the initial imaging session. A patented focus-lock mechanism ensures that the subsequent imaging sessions do not require re-focusing of the lens by default, unless required by the user. The focus is maintained for the duration of multiple behavior sessions thus enabling an accurate longitudinal assessment of neuronal subpopulations.

The Chromatone^TM software provides a flexible and customizable platform that enables optogenetics protocols, live data extraction, visualization and advanced analysis. The software enables the following capabilities:

• The various color channels (RGB images) can be separated from each other. 
• Power levels emitted for each illumination color can be set independently in each imaging fiber bundle. 
• The light delivery of each illumination color can either be set to continuous wave for imaging or pulsed for optogenetics. 
• Triggered optogenetic stimulation conditioned on specific behavioral tasks.
• Three level programing enables the most sophisticated optogenetics protocols.