University of Oregon scientists, using transgenic mice and advanced imaging technologies, capture brain-wide view of neural activity
University of Oregon scientists have looked into the brains of living mice to see in real time the processing of sensory information and generation of behavioral responses.
Using a specially customized wide-field microscope with dual lenses, University of Oregon researchers were able to put together a phase map showing regions of the mouse cortex that are active while encoding sensory stimuli. Colors indicate spatial positions (in azimuth) that elicit the largest responses.
Credit: Courtesy of Joseph Wekselblatt
To do so, researchers developed a line of transgenic mice whose brains expressed a green fluorescent protein that lights up active neurons. They then used a customized wide-field microscope with dual lenses to capture images of the brain similar to what fMRI does in humans. Combined, the technique allows them to visualize the activity across cortex, the outer surface of the brain.
"This is like fMRI but with far greater temporal and spatial resolution, " said Cristopher M. Niell, a professor in the Department of Biology and member of the UO's Institute of Neuroscience. "We can visualize sensory inputs as they come into the brain, and the subsequent activity corresponding to a decision and behavioral response. We see the whole flow."
The wide-field imaging approach developed for the research provides a new tool that can serve as a bridge connecting human fMRI to live imaging of mice to explore the underlying mechanisms and genetics of brain function and development, said Niell and UO doctoral student Joseph B. Wekselblatt.
They are two of the four UO co-authors on a paper, which is now in press with the Journal of Neurophysiology.
Large-scale brain imaging is currently possible in smaller species, such as zebrafish and nematodes, but they lack cortex -- the top layer of mammalian brains where cognition, memory, language learning and motor behaviors occur.
The visualization is possible because of the fluorescent protein, GCaMP6, which was developed by researchers at the Howard Hughes Medical Institute. The protein contains a calcium sensor and lights up when neurons are activated. The mouse line with GCaMP6 generated at the UO is being distributed to scientists around the world through a repository at Jackson Laboratory in Maine.
The transgenic mice can be followed throughout their lives, enabling the study of changes in brain function over extended periods of time, such as throughout the learning of a task. It also opens the possibility, Niell said, to explore brain issues associated with early development, adolescent behavior, schizophrenia and age-related deterioration of the brain.
Human brain studies done with fMRI, a specially developed use of magnetic resonance imaging, allows researchers to pinpoint specific regions of the brain that are active under certain conditions by measuring changes in the level of blood oxygen. It does not allow researchers to probe deeper to see specific neuronal circuitry occurring as tasks are performed.
The final step of the new mouse-imaging system involves two-photon imaging, which allows researchers to zoom in and see individual neurons that are active. Using the combination of wide-field and two-photon imaging, the researchers can study activity from the brain-wide global scale down to the local scale of groups of individual neurons.
"We deliver sensory inputs -- moving images -- that trigger decision-making by the mouse," Niell said. "As the inputs are registered and behavior begins, we can watch the flow of activity across the brain. You see it all in real time, and very quickly, nearly at the speed of thought."
"Our approach is faster than fMRI, where monitoring response is often measured in seconds," Wekselblatt said. "We see responses in a hundred milliseconds, and we can see the information flowing through cortex. You can't get that with fMRI. And then you can zoom in to see the circuitry behind the activation.
"In previous research, you'd have to use different animals at different times of their lives to get to information that you want," he said. "Here we can study the same mice over time to observe how patterns change when they are exposed to different variables, such as stress or medications."
By publishing their approach in the innovative methodology section of the Journal of Neurophysiology, the authors expect it will allow other researchers to use the approach in a wide range of studies of brain function, from sensory processing to cognition.
Co-authors with Niell and Wekselblatt are Erik D. Flister, a doctoral student, and Denise M. Piscopo, a staff scientist, both of Niell's lab.
The National Institutes of Health (grants T32 HD007348, F31 EY025459, DP2 EY023190 and RO1 EY023337) and the Searle Foundation supported the research.
Note: The UO is equipped with an on-campus television studio with a point-of-origin Vyvx connection, which provides broadcast-quality video to networks worldwide via fiber optic network. There also is video access to satellite uplink and audio access to an ISDN codec for broadcast-quality radio interviews.
Paper, early view abstract: http://jn.
Niell faculty page: http://ion.
Department of Biology: http://biology.
Institute of Neuroscience: http://ion.
UO Transgenic mouse facility: http://hgem.
Jackson Lab: https:/
Jim Barlow | EurekAlert!
Artificial intelligence may help diagnose tuberculosis in remote areas
25.04.2017 | Radiological Society of North America
Pharmacoscpy: Next-Generation Microscopy
25.04.2017 | CeMM Forschungszentrum für Molekulare Medizin der Österreichischen Akademie der Wissenschaften
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Life Sciences
28.04.2017 | Life Sciences
28.04.2017 | Life Sciences