Category: 7. Science

Pebble accretion provides new insights into Earth’s building blocks and early protoplanetary disk conditions.

Here, we show that mixtures of chondritic components: metal grains, chondrules, calcium-aluminum-rich inclusions (CAIs), and amoeboid olivine aggregates (AOAs) match Earth’s major element composition (Fe, Ni, Si, Mg, Ca, Al, O) within uncertainties, whereas no combination of chondrites and iron meteorites does.

Our best fits also match the ϵ54Cr and ϵ50Ti values of Earth precisely, whereas the best fits for chondrites, or components with a high proportion of E chondrules, fail to match Earth. In contrast to some previous studies, our best-fitting component mixture is predominantly carbonaceous, rather than enstatite chondrules.

It also includes 15 wt% of early-formed refractory inclusions (CAIs + AOAs), which is similar to that found in some C chondrites (CO, CV, CK), but notably higher than NC chondrites. High abundances of refractory materials are lacking in NC chondrites, because they formed after the majority of refractory grains were either drawn into the Sun or incorporated into terrestrial protoplanets via pebble accretion.

We show that combinations of Stokes numbers of chondritic components build 0.35-0.7 Earth masses in 2 My in the Hill regime accretion, for a typical pebble column density of 1.2 kg/m² at 1 au. However, a larger or smaller column density leads to super-Earth or moon-mass bodies, respectively. Our calculations also demonstrate that a few My of pebble accretion with these components yields a total protoplanet mass inside 1 au exceeding the combined masses of Earth, Moon, Venus, and Mercury.

Accordingly, we conclude that pebble accretion is a viable mechanism to build Earth and its major element composition from primitive chondritic components within the solar nebula lifetime.

Schematic of the secular variation of the early solar system materials. (a) 0-0.7 My: The refractory grains condense close to the Sun. Some refractory grains scattered to the outer solar system by turbulent diffusion are ultimately incorporated in later-formed bodies. Metal grains and the early generation of chondrules form further away from the Sun. Planetesimal formation takes place at this stage by gravitational or streaming instabilities (Johansen and Lambrechts, 2017). (b) ~1-2 My: Chondrule production continues. Protoplanets form by pebble accretion. Chondrite accretion begins. (c) ~2-4 My: Chondrule production and pebble accretion continue with some addition of C chondrules to the inner solar system bodies due to incomplete capture by Jupiter (Johansen et al., 2021). Inner planets are not shown here. astro-ph.EP

Susmita Garai, Peter L. Olson, Zachary D. Sharp

Comments: 9 figures, 57 pages (pre-print), accepted for publication at the Geochimica et Cosmochimica Acta (GCA)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2507.16057 [astro-ph.EP] (or arXiv:2507.16057v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2507.16057
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Related DOI:
https://doi.org/10.1016/j.gca.2024.11.021
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Submission history
From: Susmita Garai
[v1] Mon, 21 Jul 2025 20:47:54 UTC (2,626 KB)
https://arxiv.org/abs/2507.16057

Astrobiology,

Sub-Neptunes are small planets between the size of the Earth and Neptune. The orbital and bulk properties of transiting sub-Neptunes can provide clues for their formation and evolution of small planets.

In this paper, we report on follow-up observations of a planetary system around the mid-M dwarf TOI-654, whose transiting sub-Neptune TOI-654 b (P=1.53 day) is validated as a suitable target for the atmospheric observation.

We measure the planetary mass and stellar properties with the InfraRed Doppler instrument (IRD) mounted on the Subaru telescope and obtain the stellar and planetary properties from additional transit observations by the Transit Exoplanetary Survey Satellite (TESS) and a series of the Multicolor Simultaneous Camera for studying Atmospheres of Transiting exoplanets (MuSCAT). As a result, the planetary mass of TOI-654 b is determined to be M_p=8.71±1.25M_⊕, and the radius is updated to be R_p=2.378±0.089R_⊕.

The bulk density suggests that the planet is composed of a rocky and volatile-rich core or a rocky core surrounded by a small amount of H/He this http URL-654 b is one of unique planets located around the radius valley and and also on the outer edge of the Neptune desert.

The precise mass determination enables us to constrain the atmospheric properties with future spectroscopic observations especially for the emission by the James Webb Space Telescope and Ariel.

Kai Ikuta, Norio Narita, Takuya Takarada, Teruyuki Hirano, Akihiko Fukui, Hiroyuki Tako Ishikawa, Yasunori Hori, Tadahiro Kimura, Takanori Kodama, Masahiro Ikoma, Jerome P. de Leon, Kiyoe Kawauchi, Masayuki Kuzuhara, Gaia Lacedelli, John H. Livingston, Mayuko Mori, Felipe Murgas, Enric Palle, Hannu Parviainen, Noriharu Watanabe, Izuru Fukuda, Hiroki Harakawa, Yuya Hayashi, Klaus Hodapp, Keisuke Isogai, Taiki Kagetani, Yugo Kawai, Vigneshwaran Krishnamurthy, Tomoyuki Kudo, Takashi Kurokawa, Nobuhiko Kusakabe, Jun Nishikawa, Stevanus K. Nugroho, Masashi Omiya, Takuma Serizawa, Aoi Takahashi, Huan-Yu Teng, Yuka Terada, Akitoshi Ueda, Sébastien Vievard, Yujie Zou, Takayuki Kotani, Motohide Tamura

Comments: 15 pages, 11 figures, accepted for publication in PASJ
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:2507.16222 [astro-ph.EP] (or arXiv:2507.16222v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2507.16222
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Submission history
From: Kai Ikuta
[v1] Tue, 22 Jul 2025 04:35:27 UTC (4,413 KB)
https://arxiv.org/abs/2507.16222
Astrobiology,

In a new study, Northwestern University neurobiologists found the brain’s internal GPS changes each time we navigate a familiar, static environment.

This means that if someone walks the same path every day – and the path and surrounding conditions remain identical – each walk still activates different “map-making” brain cells, or neurons.

Not only does this discovery shed light on the fundamental mystery of how the brain processes and stores spatial memories, but it also could have profound implications for scientists’ understanding of memory, learning and even aging.

The study will publish on Wednesday (July 23) in the journal Nature.

Our study confirms that spatial memories in the brain aren’t stable and fixed. You can’t point to one group of neurons in the brain and say: ‘That memory is stored right there.’ Instead, we’re finding that memories are passed among neurons. The exact same experience will involve different neurons every time. It’s not a sudden change, but it slowly evolves.”

Daniel Dombeck, study’s senior author, Northwestern University

Dombeck is a professor of neurobiology and the Wender-Lewis Teaching and Research Professor at Northwestern’s Weinberg College of Arts and Sciences. The study was a collaboration among Dombeck and three members of his laboratory: Jason Climer, Heydar Davoudi and Jun Young Oh. Climer, who is one of the study’s co-first authors, is now an assistant professor of molecular and integrated physiology at the University of Illinois, Urbana-Champaign.

A memory mystery

Located deep within the brain’s temporal lobe, the hippocampus stores memories related to spatial navigation. For decades, neurobiologists thought the same hippocampal neurons encoded memories of the same places. In other words, the path someone might take from their bedroom to their kitchen should activate the exact same sequence of neurons during each midnight walk for a glass of water.

About 10 years ago, however, scientists imaged mice’s brains as they ran through a maze. Even as the mice ran through the same maze day after day, different neurons fired during each run. Scientists wondered if the results were a fluke.

“People in the field started to wonder if the mice were truly having the same experience during each run through the maze,” Dombeck said. “Maybe they run faster on some days. Maybe the smells change from day to day. Maybe there are subtle, unavoidable environmental or behavioral differences that change the overall experience.”

‘We controlled for everything we possibly could’

To probe these questions, Dombeck and his team designed an experiment that gave them unprecedented control over the mice’s sensory input. First, the team employed a cutting-edge multisensory virtual reality system – previously developed in Dombeck’s laboratory – to guarantee the animals’ experienced identical visual cues. Then, the mice ran through the virtual maze on treadmills, ensuring precise measurement of speed. Finally, the scientists put cones on the mice’s noses to provide identical smells for every session.

After running the experiment several times, the results were clear. Even in a highly reproducible virtual world, the encoded neurons still drifted. The finding confirmed that the brain’s spatial maps are inherently dynamic, constantly updating regardless of how static a space might be.

“We controlled for everything we possibly could,” Dombeck said. “I was convinced we were going to get the opposite result and show that memories really are identical for the same space. But it turns out, they are not. A slightly different group of neurons activated each time.”

Implications for aging

Although few patterns arose throughout the course of the experiment, Dombeck and his team did notice one consistent factor. The most excitable neurons, which were more easily activated, maintained more stable spatial memories throughout multiple runs through the virtual maze. Because neuron excitability decreases with age, the finding could help scientists understand the role of aging as it relates to the brain’s ability to encode new memories.

“Some neurons do seem to be better at holding onto the original memory than others,” Dombeck said. “Really excitable neurons seem to store memories the best. The ones that fire more weakly are the ones that end up changing. So there does seem to be some small component of the original memory that’s still there in this small fraction of neurons.”

Dombeck and his team are still pondering why the activated neurons change even though the space remains exactly the same. Although he’s still unsure, Dombeck said the reason might be related to time.

“Even if you have the exact same experience, it has to be occurring at a different time,” Dombeck said. “If I hike the same path twice, and it’s identical both times, I probably still want to remember that I did the same hike twice. It’s possible that the brain forces us to take very similar experiences that occur at different times and remember them in slightly different ways. That gives us access to memories of those individual experiences.”

The study, “Hippocampal representations drift in stable multisensory environments,” was supported by the National Institutes of Health (grant number R01MH101297, T32AG020506 and 1F32NS116023).

Radioastronomical observations have recently discovered PAHs of moderate size (up to 24 carbon atoms) in cold dark clouds, although it is currently unknown whether they are formed in situ through a bottom-up mechanism or from larger PAHs (20-100 carbon atoms) inherited from a previous diffuse stage in a top-down scenario.

Infrared observations have recently shown that large PAHs present in UV-illuminated regions are strongly enriched in deuterium. In order to shed light on the origin of PAHs in cold clouds, we have searched for deuterated benzonitrile in the cold dark cloud TMC-1.

To that purpose we have synthesized the three isomers (ortho, meta, and para) of monodeuterated benzonitrile, measured their rotational spectra across the 2-18 GHz and 75-110 GHz frequency ranges in the laboratory, and searched for them in TMC-1 using data from the QUIJOTE line survey.

We did not detect any of the three species and have derived a 3sigma upper limit on the column density of each of them of 3.0e10 cm^-2, meaning a fractional abundance relative to H₂ of <3e^-12. We derived a D/H ratio (which we define as the total number of D atoms with respect to the total number of H atoms present in benzonitrile) of <1.2 %.

This value is in line with the range of D/H ratios observed for other molecules in TMC-1 (0.06-3.3 %), where deuterium enrichment is explained in terms of isotopic fractionation at low temperature. It is however below the range of D/H ratios derived for large unspecific PAHs from JWST observations of the galactic PDRs Orion Bar and M17 and the galaxies M51 and NGC3256-S (between 1% and <17%).

Although it is not straightforward to compare the deuteration of PAHs in dark and UV-irradiated clouds, our results suggest that the population of PAHs detected in cold dark clouds does not result from the fragmentation of larger PAHs inherited from the previous diffuse stage in a top-down scenario.

A. L. Steber, J. Janeiro, C. Cabezas, M. Agundez, M. Pereira-Santaella, C. Perez, D. Perez, D. Heras, A. Lesarri, I. Garcia-Bernete, J. R. Goicoechea, J. Cernicharo

Comments: Accepted for publication in A&A
Subjects: Astrophysics of Galaxies (astro-ph.GA)
Cite as: arXiv:2507.16552 [astro-ph.GA] (or arXiv:2507.16552v1 [astro-ph.GA] for this version)
https://doi.org/10.48550/arXiv.2507.16552
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Submission history
From: Marcelino Agundez
[v1] Tue, 22 Jul 2025 13:04:05 UTC (4,134 KB)
https://arxiv.org/abs/2507.16552
Astrobiology, Astrochemistry,

Description

We are pleased to announce the inaugural open community event for NASA’s Habitable Worlds Observatory, to be held at the Johns Hopkins Bloomberg Center in Washington, DC, from July 28‐31, 2025. This milestone event will bring together scientists, engineers, industry and community stakeholders to propel the development of HWO, a mission expected to usher in a new era of astrophysics discovery and address one of humanity’s oldest questions “Are we alone?”

Location
Johns Hopkins Bloomberg Center (DC)
555 Pennsylvania Avenue NW
Washington, DC 20001

Welcome packet

Registration is now closed. A non-interactive livestream of the plenary sessions will be available for public viewing at the STScI Research YouTube Channel. Recordings of both plenary and parallel session talks will be made available after the close of the event.

The Habitable Worlds Observatory is NASA Astrophysics’ next flagship mission, and builds on the heritage of the Hubble, Webb, and Roman Space Telescopes. It will deploy advanced ultraviolet, optical, and infrared technologies to identify potentially habitable worlds and analyze their atmospheres for signs of life. This same technology will empower astronomers to address fundamental, persistent questions in cosmology, galaxy evolution, the origins of elements, and our Solar System’s place in the universe.

HWO has made significant progress in the past year, with NASA establishing a dedicated Technology Maturation Project Office at Goddard Space Flight Center, working in close collaboration with the Jet Propulsion Laboratory, Ames Research Center, and Marshall Space Flight Center. This initiative advances critical technologies and science cases, and fosters collaboration across government, academia, and industry. Results of HWO working groups will be showcased together with contributions from the global astronomy and engineering communities.

Topics of interest include, but are not limited to:

Science

• Galaxy Growth: Cosmic Web (Intergalactic & Circumgalactic Medium), Active Galactic Nuclei & Black Holes, Galaxy Evolution
• Evolution of the Elements: Stars & Stellar Populations, Star Formation & Interstellar Medium, Cosmic Explosions
• Cosmology: Nature of Dark Matter & Dark Energy, Distance Scale, Hubble Tension
• Planetary Systems: Formation, Evolution, Architectures, Our Solar System, Exoplanet Demographics
• Search for Life: Target Stars & Systems, Biosignatures, Habitability

Technology

• Starlight Suppression: Contrast Technology & Methods
• Ultrastable Telescope and Observatory Technology
• Ultraviolet, Optical, & Near-Infrared Instrument Technologies: mirror coatings, gratings, detectors, spectroscopic multiplexing technologies
• L2 Servicing technology and commercial synergies
• Emerging Technologies: photonics, quantum sensing
• Artificial Intelligence and Machine Learning for mission development, engineering, science research

Accepted presenters will be invited to contribute to the HWO25 proceedings, which will serve as the foundation for the first HWO Community Science Book.

Astrobiology,

After careful consideration and thorough evaluation of our current work priorities, resources, and budget constraints, we have decided to transition the Genesis collection from an active collection into preservation-mode. While the Genesis collection is in preservation-mode, we will still safeguard the long-term integrity of the collection, maintain loan agreements for samples that are currently allocated, and accept returned samples.

However, we will no longer allocate new samples or undertake additional characterization work in the collection.

This decision was not made lightly. The Genesis Collection has been a valuable resource for the scientific community, contributing to groundbreaking science and advancing our understanding of our Sun and the Solar System.

However, in recent years, the number of sample requests for Genesis samples have declined significantly. In light of evolving priorities and the need to allocate resources more effectively, this step is necessary to ensure the sustainability and continued excellence of our broader scientific endeavors, including paving the way for future sample return missions.

I understand that this news may be disappointing, particularly to those of you who have worked on the Genesis Collection for your research. Please be assured that we are committed to safeguarding the long-term integrity of this collection and will consider reopening for requests at some point in the future.

We will accept scientific requests for Genesis samples until Friday 5th September, 2025.
I deeply appreciate your understanding and continued support as we navigate these changes. Our commitment to advancing scientific knowledge remains unwavering, and I am confident that this decision will ultimately strengthen the collective efforts of NASA’s Astromaterials Acquisition and Curation Office.

The Astromaterials Newsletter is our exclusive mechanism for announcing new samples and sample targets of opportunity that are available for request. It is also our venue for providing any updates or announcements about each of the collections.

Thank you for your interest in the NASA Astromaterials Collections. Should you have any questions relating to this matter, please don’t hesitate to reach out.

Jemma Davidson, Astromaterials Curator

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Earlier post

NASA Astromaterials Newsletter
Judith Allton, Genesis Curator
Volume 7 No. 1 • April 2025

Genesis Sample Return 20th Anniversary: Looking Backward and Forward

There was a special session at the annual Lunar and Planetary Science conference (LPSC) in Houston last month that celebrated the 20th anniversary of the Genesis sample return. It comprised of 11 oral and six poster presentations, offering an example of the power of sample return missions to overcome challenges to achieve science goals – plus a lot more. Synergies with heliophysics and space weathering have come from Genesis samples.
“Serendipity” (Westphal) and “unexpected” (Jurewicz) described discoveries. Genesis PI Don Burnett paid tribute to Kuni Nishiizumi’s efforts as “heroic”. Younger scientists (e.g., Figure 1) were able to connect to learn and to share their ideas. There is still much science to be achieved from Genesis samples – including the novel use of secondary ion mass spectrometry (SIMS) data for statistical resolution of differences in solar wind velocity, useful for solar modeling. See more details in the LPSC 2025 program.

Laboratory Update

A Leica optical microscope with the capability for 3-D stacking of images was recently installed (Figure 3), which will be useful for characterizing damage dings or small particles on collectors. A small silicon collector, imaged with the new microscope, is shown below (Figure 4).

Implant Standard Project Update

To date, 63 implant standard reference pieces have been incorporated into the Genesis database by the handling and documentation procedure described in Calva et al. (2025) LPSC 2025, abstract #1175. Five separate implant sessions are associated with a variety of collector materials (silicon, silicon on sapphire, sapphire, diamond-like-carbon on silicon). Implanted ions include 34-S, 35-Cl, 13-C, 36-Ar. The next step in the process of making these available is to develop the criteria for sample control and distribution.

Sample Requests

You can find our Genesis sample catalog and the form for requesting samples online:
Catalog – Solar Wind Samples Catalog (nasa.gov)
Online Sample Request Form – Genesis Sample Request Documents and Forms (nasa.gov)
Contact Judy Allton or Carla Gonzalez via email to set up a TEAMS meeting.

Astrobiology, Astrochemistry, Astrogeology, Space Weather,

What can planets orbiting red dwarf stars teach scientists about planetary formation and evolution? This is what a recently submitted study hopes to address as an international team of researchers investigated new data obtained about a four-planet system, along with the discovery of a fifth planet. This study has the potential to help researchers better understand the formation and evolution of planets orbiting red dwarf stars, the latter of which are smaller and cooler than our Sun.

For the study, the researchers used a combination of ground-based and space-based telescopes, to estimate the sizes and masses of four exoplanets that comprise the L 98-59 system, which is located approximately 35 light-years from Earth. While three of the planets were discovered in 2019 and the fourth planet was discovered in 2021, this is the first time researchers have been able to measure their sizes and masses.

For the planets discovered in 2019, identified as L 98-59 b, c, and d, the researchers estimated their radii to be approximately 0.837, 1.329, and 1.627 Earths, respectively. The radius of the planet discovered in 2021, planet e, was estimated using computer models at approximately 1.42 Earths. The masses of the four planets were estimated to be approximately 0.46, 2.00, 1.64, and 2.82 Earths, respectively.

To complement the new estimates, the researchers also discovered a fifth planet within the system, identified as planet f, with an estimated radius and mass of 1.43 and 2.80, respectively, with the radius being estimated using computer models similar to planet e. All five planets have estimated orbital periods of 2.253, 3.691, 7.451, 12.83, and 23.06 days, respectively, for which planet f is the only planet that orbits within the star’s habitable zone.

While all the planets are hypothesized to be rocky worlds, the researchers hypothesize that planets b and c experience volcanism from tidal heating while planet d is hypothesized to be a “water world” due to its low density.

“With its diversity of rocky worlds and range of planetary compositions, L 98-59 offers a unique laboratory to address some of the field’s most pressing questions: What are super-Earths and sub-Neptunes made of? Do planets form differently around small stars? Can rocky planets around red dwarfs retain atmospheres over time?” said Dr. René Doyon, who is a Professor in the Department of Physics at Université de Montréal, Director of the Trottier Institute for Research on Exoplanets, and a co-author on the study.

What new insights will the L 98-59 system provide astronomers into planetary formation and evolution in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

Sources: arXiv, EurekAlert!

Featured Illustration Credit: Benoit Gougeon, Université de Montréal

Beyond plans to return astronauts to the Moon for the first time since the Apollo Era, NASA and other space agencies have their sights trained on Mars, Venus, and other deep-space destinations. To accomplish this, robust power systems are needed to provide ample power for spacecraft instruments and propulsion systems, thus reducing overall transit times. To this end, NASA is considering Radioisotope Power Systems (RPS), which have been used by the agency for over 60 years, most recently with the Curiosity and Perseverance rovers on Mars and the upcoming Dragonfly mission destined for Titan.

Historically, RSPs have relied on plutonium-238 as a heat source, which generates heat through slow radioactive decay. However, NASA is facing a potential shortage of this isotope, given that the U.S. Department of Energy (DoE) ceased production after the Cold War and stockpiles are dwindling. To address this, the Thermal Energy Conversion Branch at NASA’s Glenn Research Center and the University of Leicester have partnered to investigate Americium-241 as an alternative. This element could be an additional RPS heat source, powering future long-duration missions to destinations far beyond the Earth-Moon system.

For more than 15 years, researchers at the University of Leicester have been leaders in the development of Americium-RPS and heater units. Since the agreement was reached back in January, these researchers have been working with NASA scientists to evaluate the capabilities of a Stirling generator testbed powered by two electrically heated Americium-241 simulators. The University of Leicester provided the heat simulators and generator housing, while the Stirling Research Lab at NASA Glenn provided the test station, the Sterling hardware, and support equipment.

Said Hannah Sargeant, a research fellow at the University of Leicester:

A particular highlight of this (testbed) design is that it is capable of withstanding a failed Stirling convertor without a loss of electrical power. This feature was demonstrated successfully in the test campaign and highlights the robustness and reliability of an Americium-Radioisotope Stirling Generator for potential future spaceflight missions, including long-duration missions that could operate for many decades.

These tests achieved their performance and efficiency target, thereby demonstrating that an Americium-fueled RPS could be a viable power source for future missions. China also plans to send crewed missions to the Moon by 2030 and Mars sometime in the next decade. To this end, they are also pursuing Stirling engines for nuclear power systems to meet the energy needs of long-duration missions. Recently, a team of Chinese scientists created an analytical model to evaluate the design and performance of a Space Nuclear Reactor Power System (SNRPS) powered by a Stirling engine. In 2023, the crew of Shenzhou-15 completed the country’s first in-orbit test of a Sterling thermoelectric converter aboard the Tangong space station.

For their next step, the NASA Glenn team is working on the next version of the testbed, which will be lighter and higher-fidelity, and subject it to environmental testing. Said Salvatore Oriti, a mechanical engineer at NASA Glenn:

The concept started as just a design, and we took it all the way to the prototype level: something close to a flight version of the generator. The more impressive part is how quickly and inexpensively we got it done, only made possible by a great synergy between the NASA and University of Leicester teams.

We were on the same wavelength and shared the same mindset. I was very pleased with how smoothly everything went. Usually in my experience, you don’t accomplish everything you set out to, but we did that and more. We plan to continue that level of success in the future.

A review published in Advanced Science highlights the evolution of research related to implantable brain-computer interfaces (iBCIs), which decode brain signals that are then translated into commands for external devices to potentially benefit individuals with impairments such as loss of limb function or speech.

A comprehensive systematic review identified 112 studies, nearly half of which have been published since 2020. Eighty iBCI participants were identified, mostly participating in studies concentrated in the United States, but with growing numbers of studies from Europe, China, and Australia.

The analysis revealed that iBCI technologies are being used to control devices such as robotic prosthetic limbs and consumer digital technologies. Although most studies reported outcome measures prospectively, these mostly related to device performance, with only 17.9% assessing patients’ clinical outcomes. When clinical outcomes were assessed, these were highly mixed because of varied approaches in different patient populations.

Implantable BCIs hold enormous promise, but the key challenge is proving their effectiveness. In this analysis, we provide the most up-to-date estimate of global iBCI trial participants and examine which outcome measures are being used. These insights are used to offer concrete guidance for designing future iBCI trials.”

Esmee Dohle, MB BChir, first author, Oxford University Hospitals, UK

Corresponding author Jamie Brannigan, MB BChir, of University College London in the UK and Mount Sinai Hospital in the US noted that the team has created the first global registry of iBCI trial participants, mapping which participants have been implanted, where, and with what type of device.

“There is now an opportunity for the community to provide feedback on this registry and for us to build upon this first effort,” he said. “We believe this will enable the field to more easily track progress, avoid duplication, and align future trials with unmet clinical needs.”