Calcium imaging enables neuroscientists to visualize the activity of large neuronal populations using fluorescent activity indicators (Grienberger & Konnerth, 2012). The invention of imaging technologies, such as the optical fiberscope or miniscope, allows for calcium imaging to be performed in freely-behaving animals with single-cell resolution (
All-Optical Electrophysiology: Integrating Voltage Imaging and Optogenetics
The invention of optogenetics has enabled scientists to use light to turn cell-type specific neural activity on or off with millisecond-precision to probe neural circuit function (Yizhar et al. 2011). Complementing optogenetics, voltage imaging enables scientists to observe cell-type specific neural circuit activity with cellular-resolution...
What Equipment Do You Need for Voltage Imaging?
If someone were to describe voltage imaging to you, it might sound quite simple. When you dig deeper, you start to appreciate the complexity associated with the biology and equipment to perform voltage imaging. You’re probably asking, what are the necessary components to perform voltage...
Electrophysiology is the golden standard for recording individual neuron activity. By recording electrical changes across the cell membrane, electrophysiology is able to detect action potentials in real-time (Petersen, 2017). Due to the complex nature of the technique, however, electrophysiology cannot be used to measure the activity of...
Integrating Complementary Optical Techniques with Intrinsic Optical Imaging
Intrinsic optical imaging has its strengths and weaknesses, like many techniques. Many researchers employ this technique because it is non-invasive, requiring very little surgical intervention and minimal equipment (Juavientt et al., 2018). Intrinsic optical imaging provides a large field-of-view with relatively good spatial and temporal precision...
What Components are Required for Intrinsic Optical Imaging?
Intrinsic optical imaging (or intrinsic signal imaging) is a simplistic imaging method that enables scientists to indirectly record neural activity in large cortical regions non-invasively by measuring hemodynamic changes in the brain (Morone et al., 2017). You’re probably asking, what are the necessary components to...
What is Intrinsic Optical Imaging?
Current advanced imaging techniques, such as calcium imaging, can record cortical activity with high spatial precision and cell-type specificity using the expression of fluorescent sensors and implantation of a cortical window; however, this technique can be quite invasive and complex. For head-fixed experiments measuring general changes in...
Selecting An Optogenetic Light Source: LED vs. Laser
When selecting an optogenetic light source, you will consider two key factors: the required light wavelength and intensity. First, the opsin you select has a specific activation spectrum, such that an opsin will only be activated by certain wavelengths of light. An opsin usually has a peak...
How Can Patterned Illumination be Used in Optogenetics Experiments? (Part 3)
How Can Patterned Illumination be Used in Optogenetics Experiments? (Part 2)
What Systems are Available for Cellular-Resolution Optogenetics?
The ability to illuminate select neurons within a population of optogenetic-expressing neurons is called cellular-resolution optogenetics (Shemesh et al. 2017). Using this technique, researchers require more sophisticated spatial specificity to selectively stimulate individual neurons within an optogenetic-expressing population. The development of spatially targeted light...
How Can Patterned Illumination be Used in Optogenetics Experiments? (Part 1)
Patterned illumination technologies enable researchers to selectively illuminate parts of their sample for optogenetic stimulation. One application of this is cellular-resolution optogenetics: the ability to selectively illuminate individual neurons within an optogenetic-expressing population (to further understand the difference between widefield and cellular-resolution optogenetics, see this blog...