Findings, in mice, fuel the idea that processes of active movement and sensory processing are connected
A new study by researchers at the University of Oregon published today in the journal Neuron describes a brainstem circuit in mice that may help explain how active movement impacts the way the brain processes sensory information.
Christopher Niell, a biologist and member of the University of Oregon's Institute of Neuroscience, directed a team that provided new details in the journal Neuron about a brainstem circuit in mice that may help explain how active movement impacts the way the brain processes sensory information.
Credit: University of Oregon
"Previous studies have examined changes in the visual cortex of mice during running. What was unknown was how do running and vision get linked together in the first place?" said Cristopher Niell, a biology professor in the Institute of Neuroscience and the senior author on the paper "Identification of a Brainstem Circuit Regulating Visual Cortical State in Parallel with Locomotion."
The "aha moment" that inspired the study came five years ago when Niell, as a postdoctoral fellow in Michael Stryker's lab at the University of California, San Francisco, was examining visual perception in mice. He observed that running appeared to be changing how neurons in the brain were firing.
"We found that running turned up the magnitude in the mouse's visual cortex by about two-fold — the signals were basically twice as strong when the mouse was running," Niell said.
This initial finding, demonstrating a mind-body connection in the mouse visual system, was published in Neuron in 2010. Following up on this finding, Niell's team sought to identify neural circuits that could link movement and vision together.
The researchers focused on the brain's mesencephalic locomotor region (MLR), which has been shown to mediate running and other forms of activity in many species. They hypothesized that neural pathways originating in the MLR could serve a dual role – sending a signal down to the spinal cord to initiate locomotion, and another up to the cortex to turn up the visual response.
Using optogenetic methods, the team created genetically sensitized neurons in the MLR region of the mouse brain that could be activated by light. The team then recorded the resulting increased visual responses in the cortex. Their results demonstrated that the MLR can indeed lead to both running and increased responsiveness in the cortex, and that these two effects could be dissociated, showing that they are conveyed via separate pathways.
Next, researchers activated the terminals of the neurons' axons in the basal forebrain, a region that sends neuromodulatory projections to the visual cortex. Stimulation here also induced changes in the cortex, but without the intermediary step of running. Interestingly, the basal forebrain is known to use the neuromodulator acetycholine, which is often associated with alertness and attention.
It is unclear whether humans experience heightened visual perception while running, but the study adds to growing evidence that the processes governing active movement and sensory processing in the brain are tightly connected. Similar regions have been targeted in humans for therapeutic deep-brain stimulation to treat motor dysfunction in patients with Parkinson's disease. Activating this circuit might also provide a means to enhance neuroplasticity, the brain's capacity to rewire itself.
Niell's team included Moses Lee, a visiting scholar at the UO and student in the M.D.-Ph.D. program at UC-San Francisco, who served as the lead author on the paper. "While it seems that moving and sensing are two independent processes, a lot of new research suggests that they are deeply coupled," Lee said. "My hope is that our study can help solidify our understanding of how the brain functions differently in 'alert' states."
Other authors were Jennifer Hoy of the UO, Antonello Bonci of the National Institute of Drug Abuse and Johns Hopkins School of Medicine, Linda Wilbrecht of the UC-Berkeley, and Stryker. Research in the Niell lab at the UO was conducted over the past three years with funding from the National Institutes of Health. NIH grants supporting the research were 1R01EY023337 to Niell, 1R01EY02874 to Stryker and 1RC2NS069350 and 1R01MH087542 to Wilbrecht.
About the University of Oregon The University of Oregon is among the 108 institutions chosen from 4,633 U.S. universities for top-tier designation of "Very High Research Activity" in the 2010 Carnegie Classification of Institutions of Higher Education. The UO also is one of two Pacific Northwest members of the Association of American Universities.
Source: Cristopher Niell, assistant professor, Department of Biology, 541-346-8598, firstname.lastname@example.org
Niell faculty page: http://uoneuro.uoregon.edu/ionmain/htdocs/faculty/niell.html
Institute of Neuroscience: http://uoneuro.uoregon.edu/ionmain/htdocs/index.html
Department of Biology: http://biology.uoregon.edu/
University of Oregon: http://uoregon.edu/
Like UO Science on Facebook: http://www.facebook.com/UniversityOfOregonScience
Follow UO Science on Twitter: https://twitter.com/UO_Research Note: The University of Oregon 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. In addition, there is video access to satellite uplink, and audio access to an ISDN codec for broadcast-quality radio interviews.
Lewis Taylor | Eurek Alert!
Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie
Study overturns seminal research about the developing nervous system
21.04.2017 | University of California - Los Angeles Health Sciences
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...
Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...
Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.
A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
21.04.2017 | Physics and Astronomy
21.04.2017 | Health and Medicine
21.04.2017 | Physics and Astronomy