COLLEGE PARK, Md. -- Three University of Maryland engineers have been awarded new National Science Foundation (NSF) grants through an NSF program that fosters research on how human neural and cognitive systems interact and intersect with advances in engineering, computer science and education. 

These grants are among 19 NSF awards issued to U.S. cross-disciplinary teams to conduct work that is  “bold, risky, and transcends the perspectives and approaches typical of single-discipline research efforts.” According to the agency, the awards will contribute to NSF’s investments in fundamental brain research, in particular support of Understanding the Brain and the BRAIN Initiative, a coordinated research effort that seeks to accelerate the development of new neurotechnologies.

Professor Jonathan Simon, who holds joint appointments in electrical and computer engineering (ECE), biology and UMD’s Institute for Systems Research (ISR), and Assistant Professor Behtash Babadi, who holds joint appointments in ECE and ISR, have received a $900,000 grant for research that will take advantage of recent advances in noninvasive neuroimaging to learn more about how the brain’s neural mechanisms work in adaptive auditory processing. Simon and Babadi are two of more than 140 UMD faculty in the university’s Brain and Behavior Initiative, which seeks to revolutionize the interface between engineers and neuroscientists by generating novel tools and approaches to understand complex behaviors produced by the human brain.

UMD Associate Professor Sarah Bergbreiter, who holds a joint appointment in mechanical engineering and ISR,  and two colleagues from Northwestern University, L. Catherine Brinson and Mitra Hartmann, were awarded a $1,000,000 grant to better understand how animals use the sense of touch to gather information and then use this information to perform complex behaviors. The University of Maryland’s portion of the grant is $320,000.

Using brain imaging to study how our brains adapt  to varying sound environments 

Recent, growing evidence suggests that sophisticated brain functions happen when more than one region of the brain is activated at the same time, and the brain forms networks between these regions that can dynamically reconfigure. These networks allow humans to rapidly adapt to changes in their sound environment, such as when walking from a quiet street into a noisy party. Currently, little is known about the workings of these brain networks, which bind, organize, and give meaning to higher cognitive functions.

Adaptive auditory processing is one such higher function. It is the brain’s ability to attend to, segregate, and track one of many sound sources, to learn its identity, commit it to memory, robustly recognize it, and use it to make decisions. And it is in this area that the new NSF funding will support new research by Simon and Babadi. 

“Deciphering the neural mechanisms underlying the brain’s network dynamics is critical to understanding how the brain carries out universal cognitive processes such as attention, decision-making and learning,” notes Simon. “However, the sheer high-dimensionality of dynamic neuroimaging data, together with the complexity of these [brain] networks, has created serious challenges, in practice, in its data analysis, signal processing, and neural modeling.”

The researchers will use modern signal processing techniques to combine high temporal resolution, non-invasive recordings with high spatial resolutions.

“Our work will bring new insight to the dynamic organization of cortical networks at unprecedented spatiotemporal resolutions, and can thereby impact technology in the areas of brain-computer interfacing and neuromorphic engineering,” says Babadi. “It will also allow for the creation of engineering solutions for early detection and monitoring of cognitive disorders involving auditory perception and attention.”

Neuromorphic engineering is the use of a very large-scale system of integrated circuits to mimic neuro-biological architectures present in the nervous system.

Using robotic whiskers to help understand how animal brains’ use real ones

The research by Bergbreiter and her two Northwestern colleagues will advance understanding of how animals first gather information through the sense of touch and then how the use this information to perform complex behaviors.  At Maryland, Bergbreiter will be developing artificial, modular, reconfigurable whiskers that imitate the functions of animal whiskers.  

The whiskers will be mounted on robotic platforms that can mimic the head movements of animals, contributing to the development of novel robots and sensors that use touch to sense an object’s location, shape, and texture, to track fluid wakes in water, and to sense the direction of airflow.

“Engineering arrays of sensors to serve as physical models of a rat's whiskers will allow us to better understand the connections between what a rat senses and its actions,” Bergbreiter says. “Using this understanding, we can design robots with the ability to explore dark areas or work in other challenging environments that require a sense of touch or flow.”

The NSF Neural and Cognitive Science Program

The complexities of brain and behavior pose fundamental questions in many areas of science and engineering, drawing intense interest across a broad spectrum of disciplinary perspectives while eluding explanation by any one of them. Rapid advances within and across disciplines are leading to an increasingly interconnected fabric of theories, models, empirical methods and findings, and educational approaches, opening new opportunities to understand complex aspects of neural and cognitive systems through integrative multidisciplinary approaches. According to NSF this program seeks to support innovative, integrative, boundary-crossing proposals that can best capture those opportunities

"It takes insight and courage to tackle these problems," said Ken Whang, NSF program director in the Computer and Information Science and Engineering Directorate (CISE). "These teams are combining their expertise to try to forge new paths forward on some of the most complex and important challenges of understanding the brain. They are posing problems in new ways, taking intellectual and technical risks that have huge potential payoff."

COLLEGE PARK, Md. -- An international team of researchers from UMD, University of Exeter,  NASA and other institutions has found compelling evidence for a stratosphere on an enormous planet outside of the solar system. Previous research spanning the past decade has indicated possible evidence for stratospheres on planets in other solar systems, but this finding on planet, WASP-121b, is the first time that glowing water molecules have been detected—the clearest signal yet to indicate an exoplanet stratosphere.

“When it comes to distant exoplanets, which we can’t see in the same detail as other planets here in our own solar system, we have to rely on proxy techniques to reveal their structure,” said Drake Deming, a professor of astronomy at UMD and a co-author of the study. “The stratosphere of WASP-121b so hot it can make water vapor glow, which is the basis for our analysis.”

The planet, located approximately 900 light years from Earth, is a gas giant exoplanet commonly referred to as a “hot Jupiter.”  The scientists made the new discovery using NASA’s Hubble Space Telescope. The research is published in the August 3, 2017 issue of the journal Nature.

In our solar system all the planets have some kind of atmosphere, but the composition, density and number of layers vary greatly. Earth’s atmosphere has five layers, of which the troposphere is closest to the planet surface and in which temperature falls as the altitude increases. The stratosphere is the next layer and here temperatures increase with higher altitudes, a phenomena also found in the stratosphere of WASP-121b. The last three layers of Earth’s atmosphere are the mesosphere, the thermosphere, and the last layer, the exosphere, which merges with the emptiness of outer space .

To study the stratosphere of WASP-121b, scientists used spectroscopy to analyze how the planet’s brightness changed at different wavelengths of light. Water vapor in the planet's atmosphere, for example, behaves in predictable ways in response to certain wavelengths of light, depending on the temperature of the water. At cooler temperatures, water vapor blocks light from beneath it. But at higher temperatures, the water molecules glow.

The phenomenon is similar to what happens with fireworks, which get their colors when metallic substances are heated and vaporized, moving their electrons into higher energy states. Depending on the material, these electrons will emit light at specific wavelengths as they lose energy. For example, sodium produces orange-yellow light and strontium produces red light.

The water molecules in the atmosphere of WASP-121b similarly give off radiation as they lose energy, but it is in the form of infrared light, which the human eye is unable to detect.

“Theoretical models have suggested that stratospheres may define a special class of ultra-hot exoplanets, with important implications for the atmospheric physics and chemistry,” said Tom Evans, research fellow at the University of Exeter and lead author of the study. “When we pointed Hubble at WASP-121b, we saw glowing water molecules, implying that the planet has a strong stratosphere.”

WASP-121b has a greater mass and radius than Jupiter, making it much puffier. The exoplanet orbits its host star every 1.3 days, and the two bodies are about as close as they can be to each other without the star's gravity ripping the planet apart. This close proximity also means that the top of the atmosphere is heated to a blazing hot 2,500 degrees Celsius – the temperature at which iron exists in gas rather than solid form.

In Earth's stratosphere, ozone traps ultraviolet radiation from the sun, which raises the temperature of this layer of atmosphere. Other solar system bodies have stratospheres, too—methane is responsible for heating in the stratospheres of Jupiter and Saturn's moon Titan, for example. In solar system planets, the change in temperature within a stratosphere is typically less than 100 degrees Celsius. However, on WASP-121b, the temperature in the stratosphere rises by 1,000 degrees Celsius.

Though researchers have not been able to positively identify the cause of the heating they hope upcoming observations at other wavelengths to address this mystery.  

Vanadium oxide and titanium oxide gases are candidate heat sources, as they strongly absorb starlight at visible wavelengths, much like ozone absorbs UV radiation. These compounds are expected to be present in only the hottest of hot Jupiters, such as WASP-121b, as high temperatures are required to keep them in the gaseous state. Indeed, vanadium oxide and titanium oxide are commonly seen in brown dwarfs, ‘failed stars’ that have some commonalities with exoplanets.

NASA's forthcoming James Webb Space Telescope will be able to follow up on the atmospheres of planets like WASP-121b with higher sensitivity than any telescope currently in space.

"This super-hot exoplanet is going to be a benchmark for our atmospheric models, and will be a great observational target moving into the Webb era," said Hannah Wakeford, a research fellow at the University of Exeter and a co-author of the research paper.