This technology is a microscope platform that combines holographic beam multiplexing with the power of two-photon optogenetics and uncaging of photosensitive compounds for high-resolution imaging and mapping of neural circuits and functional assaying of the effect of pharmacological compounds on individual neurons.
Detecting activity of individual neurons and the spatiotemporal pattern in which they fire is an important step to understanding brain function. The modern laser scanning microscope (LSM) is a powerful tool that can be used to effectively image and optically manipulate neurons. A prominent disadvantage for such a system, however, is the generally poor temporal resolution which is limited by serial scanning rate. There are several ways to improve temporal resolution in LSM systems. One possible approach is to split the excitation light into multiple beamlets and scan different locations simultaneously. Alternatively, spinning-disk confocal microscopy or semitransparent mirror beam-splitters and galvanometer scanners can be used. However, these strategies limit the energy that is effectively available in the laser and result in a lower signal to noise ratio for the acquired image.
This technology describes an imaging technique for increasing temporal resolution in microscope systems using two-photon holographic imaging and stimulation. Specifically, the microscope is adapted with a diffractive spatial light modulator (SLM), a holographic device capable of modifying the phase profile of a laser wavefront to build a 3D light pattern, placed in the beam path of a two-photon microscope to generate multiple beamlets that can be independently and dynamically controlled. As a result, the temporal resolution is only limited by the detection rate instead of the scanning rate, which greatly improves the function of the microscope system. This technology enables simultaneous 3D imaging of neurons, eliminates wasteful wall time (repeat scans of areas that are not actively changing), and saves on total illumination power, all while delivering images at greater speeds. Furthermore, this device can stimulate individual neurons in brain slices in any spatio-temporal pattern in 3D, using two-photon optogenetics or uncaging of photo-sensitive compounds, for real time manipulation and mapping of neuronal circuits.
This technology has been demonstrated in vivo on several layers of the primary visual cortex of a living mouse and can provide a selective assay to test the effect of neuroactive compounds in neural circuits of living animals.
Patent Issued Patent Status
IR M08-107
Licensing Contact: Beth Kauderer