Trends and Characteristics of Manufactured Cannabis Product and Cannabis Plant Product Exposures Reported to US Poison Control Centers, 2017-2019

Julia A. Dilley, PhD¹; Janessa M. Graves, PhD²; Ashley Brooks-Russell, PhD³; et alJennifer M. Whitehill, PhD⁴; Erica L. Liebelt, MD^5,6

Author Affiliations Article Information

JAMA Netw Open. 2021;4(5):e2110925. doi:10.1001/jamanetworkopen.2021.10925

 May 24, 2021

Introduction

Legalization of adult use cannabis products has led to a consumer-driven marketplace. A growing share of retail cannabis sales are manufactured cannabis products,¹ which may contain higher levels of tetrahydrocannabinol (THC) than unprocessed cannabis plant materials,² resulting in greater short-term effects (eg, cognitive and psychomotor impairment).³ Public health concerns are emerging about these risks.⁴ Our study objective was to assess recent patterns in reports of cannabis-related exposures by product type.

Methods

For this cross-sectional study, we accessed National Poison Data System data on cannabis exposures reported to US poison centers for January 2017 through December 2019. Cannabis product type codes were added to the system in 2016. We compared trends and characteristics of exposures for manufactured products that require processing of plant materials (eg, concentrates, edibles, vaporized liquids) and unprocessed plant materials (eg, flower) (eMethods in the Supplement). Two-sided P values <.05 were considered statistically significant. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline for cross-sectional studies. The institutional review board at Washington State University determined this study was exempt from review because it used deidentified data.

Results

Among the total 28 630 exposures, plant materials were the most commonly involved (18 763 exposures [65.5%]), followed by edibles (5537 [19.3%]), concentrates (2734 [9.6%]), vaporized liquids (1075 [3.8%]), and other manufactured products (521 [1.8%]) (Table).

Manufactured product exposure cases more often involved children: 2505 cases (27.0%) involved patients under 10 years old, compared with 1490 plant-based exposures (8.4%). Exposures to edibles had the greatest proportion of children (1905 exposures [36.6%]). More than half of all calls were made from a health care facility; manufactured product calls came from a residence nearly twice as often as plant-based exposure calls (3927 [39.8%] vs 3817 [20.3%]; P < .001).

Most manufactured cannabis product exposures were for those products alone (8040 exposures [81.5%]). In contrast, most plant exposures (11 556 [61.6%]) also involved other agents (eg, alcohol, other drugs). Among exposures where only cannabis was involved, a slightly smaller percentage of manufactured product exposures overall (2918 [36.3%]) were associated with serious medical outcomes compared with plant-based exposures (2803 [38.9%]). Vaporized liquid exposures were most likely to have serious medical outcomes (268 [42.3%]).

During 2019, population-based rates for manufactured cannabis product exposures overall and for most specific products were greater where adult cannabis use was legal. One exception was vaping: exposure calls per 100 000 population were 0.29 in nonlegal states (692 total exposures) and 0.21 in legal states (195 total exposures).

Total cannabis exposures increased between 2017 and 2019. However, quarterly plant-related exposure reports declined over time, while manufactured product exposure reports increased overall and for each specific product (Figure).

Discussion

Our findings document that US poison centers are increasingly receiving calls about adverse events associated with exposures to manufactured cannabis products. Higher rates in legal states suggest that continued increases may be expected with adult cannabis use legalization in more states.

Children may be at particular risk for exposure to edible products, such as cookies or candy. Although we did not see more serious health outcomes for manufactured product exposures compared with plant products overall, most cannabis plant exposures involved polysubstance use, whereas most cases for manufactured products were for those products alone, suggesting that exposure to manufactured products alone may be relatively more likely to generate adverse events. This is consistent with studies of acute health effects.³

Manufactured products may present risks both because of THC levels and other processing ingredients. For example, vaporized liquid additive ingredients were implicated in a 2019 national lung injury (e-cigarette or vaping use–associated lung injury [EVALI]) outbreak.⁵

Market factors may drive the industry to continue developing novel products, which could present additional health risks. Applying regulatory controls to market-driven innovations in potency and additives is key. Novice cannabis users are often advised to “start low, go slow”; this guidance may be equally applicable to regulating new retail cannabis markets and products.

This study was limited by its data source. Poison centers provide useful information about specific product exposures and medical outcomes; however, data are self-reported and may underestimate the burden of cases. Ongoing monitoring of manufactured product–specific adverse events is recommended to understand public health concerns and effectiveness of regulations or harm reduction messaging.

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Article Information

Accepted for Publication: March 30, 2021.

Published: May 24, 2021. doi:10.1001/jamanetworkopen.2021.10925

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2021 Dilley JA et al. JAMA Network Open.

Corresponding Author: Julia A. Dilley, PhD, Program Design and Evaluation Services, Public Health Division, Oregon Health Authority, 800 NE Oregon St, Ste 260, Portland, OR 97232 (julia.dilley@multco.us).

Author Contributions: Dr Dilley had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Dilley, Graves, Brooks-Russell, Whitehill.

Acquisition, analysis, or interpretation of data: Dilley, Graves, Whitehill, Liebelt.

Drafting of the manuscript: Dilley.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Dilley.

Obtained funding: Graves.

Administrative, technical, or material support: Dilley, Graves, Liebelt.

Supervision: Graves, Liebelt.

Conflict of Interest Disclosures: Dr Graves reported receiving grants from the Alcohol and Drug Abuse Research Program at Washington State University; she reported serving on the board of directors for the Washington Poison Center outside the submitted work. Dr Whitehill reported receiving consulting fees from Washington State University during the conduct of the study. Dr Liebelt reported receiving consulting fees from Washington State University during the conduct of the study and a grant given her organization (Washington Poison Center) from Verdant Health Commission to develop curriculum and education on harmful effects of cannabis. No other disclosures were reported.

Funding/Support: This investigation was supported in part by funds provided for medical and biological research by the State of Washington (initiative measure No 171). Support for Dr Dilley was provided in part by the National Institute on Drug Abuse of the National Institutes of Health (award No 1R01DA039293).

Role of the Funder/Sponsor: The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

References

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Firth  CL, Davenport  S, Smart  R, Dilley  JA.  How high: differences in the developments of cannabis markets in two legalized states.   Int J Drug Policy. 2020;75:102611. doi:10.1016/j.drugpo.2019.102611PubMedGoogle Scholar

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Smart  R, Caulkins  JP, Kilmer  B, Davenport  S, Midgette  G.  Variation in cannabis potency and prices in a newly legal market: evidence from 30 million cannabis sales in Washington state.   Addiction. 2017;112(12):2167-2177. doi:10.1111/add.13886PubMedGoogle ScholarCrossref

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Spindle  TR, Cone  EJ, Schlienz  NJ,  et al.  Acute effects of smoked and vaporized cannabis in healthy adults who infrequently use cannabis: a crossover trial.   JAMA Netw Open. 2018;1(7):e184841. doi:10.1001/jamanetworkopen.2018.4841
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Matheson  J,, Le Foll  B.  Cannabis legalization and acute harm from high potency cannabis products: a narrative review and recommendations for public health.   Front Psychiatry. 2020;11:591979. doi:10.3389/fpsyt.2020.591979Google Scholar

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Krishnasamy  VP, Hallowell  BD, Ko  JY,  et al; Lung Injury Response Epidemiology/Surveillance Task Force.  Update: characteristics of a nationwide outbreak of e-cigarette, or vaping, product use-associated lung injury—United States, August 2019-January 2020.   MMWR Morb Mortal Wkly Rep. 2020;69(3):90-94. doi:10.15585/mmwr.mm6903e2PubMedGoogle ScholarCrossref

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US Census. 2019 national and state population estimates—population for non-legal states. Updated December 30, 2019. Accessed April 9, 2021. https://www.census.gov/newsroom/press-kits/2019/national-state-estimates.html

BROADCAST AROUND WIND TURBINES

Experimental broadcast of whitewater river noise drives bats and birds away

Intense noise reduces bird foraging activity and causes bats to switch hunting strategies

CALIFORNIA POLYTECHNIC STATE UNIVERSITY

Research News

 

IMAGE: DR. DYLAN GOMES LED THE TEAM THAT DEPLOYED SPEAKER ARRAYS EARLY IN THE SPRING TO BEGIN PLAYBACK OF WHITEWATER RIVER NOISE BEFORE MOST BIRDS AND BATS WERE USING THIS HIGH... view more 

CREDIT: DR. CORY TOTH

While many might consider a walk in the woods to be a quiet, peaceful escape from their noisy urban life, we often don't consider just how incredibly noisy some natural environments can be. Although we use soothing natural sounds in our daily lives - to relax or for meditation - the thunder of a mountain river or the crash of pounding surf have likely been changing how animals communicate and where they live for eons. A new experimental study published in the journal Nature Communications finds that birds and bats often avoid habitat swamped with loud whitewater river noise.

Dr. Dylan Gomes, a recent PhD graduate of Boise State University and first author on the paper, summarizes the aims of the work this way, "naturally-loud environments have been largely neglected in ecological research. We aimed to test the hypothesis that intense natural noise can shape animal distributions and behavior by experimentally broadcasting whitewater river noise at a massive scale." In fact, the scientists had to transport literal tons of gear across roadless terrain to place solar-powered speaker arrays in half of their 60 locations in the Pioneer Mountains of Idaho where they monitored bird and bat populations for two summers.

The speaker arrays were arranged along riparian areas, filling each bubbling brook with the auditory experience of a rushing whitewater river. The team took advantage of their experimental approach to broadcast both realistic reproductions of river noise, as well as river noise that had been shifted upwards in frequency to understand how the noise caused changes in animal numbers. "The prevailing hypothesis for why many animals avoid noise is called masking. Masking occurs when noise overlaps in frequency (what we perceive as pitch) with a biological signal or cue. By broadcasting noise of different frequencies, we hoped to assess the role that masking of important sounds, such as birdsong, plays in the avoidance of noisy places", said the senior author of the study, Dr. Jesse Barber of Boise State University. The scientists found that overlap between background noise and song frequency predicted bird declines until acoustic environments became about as loud as a highway, at which point other forces, such as an inability to hear predators and prey, likely become more important.

Understanding how noise drives animals out of otherwise good habitat is clearly important, but what about the animals that stay behind? To study foraging in birds that remained in naturally-loud places the authors set out hundreds of caterpillar decoys made of clay across their study sites. By carefully examining the types of marks predators left in the clay, the scientists found that more noise meant less foraging by birds. This means that, even after controlling for the fact that fewer birds were found in loud places, birds were less efficient at visually hunting for these silent, decoy caterpillars in the presence of noise. This is not unlike the difficulty people can experience when trying to listen to a friend talk while a muted television is on, dividing our attention.

To understand how bats that remained in noise-exposed areas fared, the team deployed two foraging puzzles to solve. The first was a "robo-moth" that lured in bats with its insect-like wing beats. The second was a speaker playing a "mix tape" of cricket and katydid calls and insect walking sounds. After almost 150 nights of data collection the scientists found that, as the world gets louder, some bats switch from listening for prey sounds to using echolocation. Dr. Gomes explains, "this behavioral switch is likely driven by prey calls and footsteps being masked by river noise and this type of problem-solving likely explains why some bats can remain near the ruckus of a raging whitewater river".

When putting all these pieces together, the authors argue that by studying how animals respond to noise sources that they have faced throughout their evolutionary history, we can get a better handle on how animals will deal with human-caused noise. Dr. Clinton Francis from California Polytechnic State University and Co-Principal Investigator of the study says, "our work showing that natural noise can structure where animals live and how they behave only increases the call to manage human-caused noise. The spatial and temporal footprint of anthropogenic noise is far greater than loud natural environments."

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Other co-authors on this paper include Dr. Cory Toth, a former postdoctoral researcher and Hunter Cole, a current Master's student, both members of the Barber Lab at Boise State University. This work was funded by the National Science Foundation and was conducted on land owned and managed by Lava Lake Ranch.

 

How do clownfish earn their stripes?

The distinctive white stripes in clownfish form at different rates depending on their sea anemone hosts, a PNAS study finds

OKINAWA INSTITUTE OF SCIENCE AND TECHNOLOGY (OIST) GRADUATE UNIVERSITY

Research News

 

IMAGE: AMPHIPRION PERCULA, A SPECIES OF CLOWNFISH PHOTOGRAPHED IN KIMBE BAY, PAPUA NEW GUINEA. view more 

CREDIT: TANE SINCLAIR-TAYLORClownfish species develop their characteristic white stripes, or bars, during the process of metamorphosis

• Researchers have now discovered that the white bars form at different speeds depending on the sea anemone the clownfish live in
• Thyroid hormones, which are important for metamorphosis, control the speed the white bars form
• Levels of thyroid hormones are higher in clownfish that live in the giant carpet anemone compared to clownfish living in the magnificent sea anemone
• Clownfish living in the giant carpet anemone also show increased activity of duox, a gene involved in forming thyroid hormones

Charismatic clownfish, the coral reef fish made famous by the film Finding Nemo, are instantly recognizable by their white stripes. These stripes, which scientists call bars, appear as clownfish mature from larvae into adults in a process called metamorphosis, but how these distinctive patterns form has long remained a mystery.

Now, a new study has found that the speed at which these white bars form depends on the species of sea anemone in which the clownfish live. The scientists also discovered that thyroid hormones, which play a key role in metamorphosis, drive how quickly their stripes appear, through changes in the activity of a gene called duox.

"Metamorphosis is an important process for clownfish - it changes their appearance and also the environment they live in, as clownfish larvae leave life in the open ocean and settle in the reef," said senior author Professor Vincent Laudet, who leads the Marine Eco-Evo-Devo Unit at the Okinawa Institute of Science and Technology Graduate university (OIST). "Understanding how metamorphosis changes depending on the sea anemone host can help us answer questions not only about how they adapt to these different environments, but also how they might be affected by other environmental pressures, like climate change."

In the study, published 24th May, 2021 in PNAS, a team of researchers from the Centre for Island Research and Environmental Observatory (CRIOBE) in France first surveyed the clownfish species, Amphiprion percula, in Kimbe bay, Papua New Guinea.

The clownfish there can live either in the magnificent sea anemone, Heteractis magnifica, or the more toxic giant carpet anemone, Stichodactyla gigantea.

During the survey, the team noticed that juvenile clownfish that lived in the giant carpet anemone gained their adult white bars faster than clownfish living in the magnificent sea anemone.

"We were really interested in understanding not only why bar formation occurs faster or slower depending on the sea anemone, but also what drives these differences," said first author Dr. Pauline Salis, a postdoctoral researcher at the Observatoire Océanologique de Banyuls-sur-Mer, Sorbonne Université Paris, who studies color patterning in coral reef fish.

In the lab, the team worked with the clownfish, Amphiprion ocellaris, a close relative of Amphiprion percula. They focused on thyroid hormones, which are known to trigger metamorphosis in frogs.

The researchers treated larval clownfish with different doses of thyroid hormones. The higher the dose of thyroid hormones, the faster the clownfish developed the white bars, the team reported. Conversely, when the researchers treated the clownfish with a drug that stopped thyroid hormones from being produced, bar formation was delayed.

The white bars form due to pigment cells, called iridophores, which express a specific subset of genes. Thyroid hormones accelerated white bar formation by activating these iridophore genes, the research team found.

Next, the scientists tested whether these observations held true the field. When the CRIOBE lab returned to Kimbe Bay, they transported juvenile clownfish from both species of sea anemone back to Dr. Salis in France.

Levels of thyroid hormones were much higher in the clownfish from the giant carpet anemone than in the clownfish from the magnificent sea anemone, Dr. Salis confirmed.

To gain insight into what caused these higher levels of thyroid hormones, the team measured the activity of most genes in the clownfish genome.

"The big surprise was that out of all these genes, only 36 genes differed between the clownfish from the two sea anemone species," said Prof. Laudet. "And one of these 36 genes, called duox, gave us a real eureka moment."

Duox, which makes the protein dual oxidase, plays an important role in the formation of thyroid hormones, previous research has shown. The duox gene showed higher levels of activity in clownfish from the giant carpet anemone, compared to clownfish from the magnificent sea anemone.

Further experiments in collaboration with Professor David Parichy from the University of Virginia, U.S., confirmed that duox is important for developing iridophore pigment cells. When the duox gene is inactivated in mutant zebrafish, development of the iridophore pigment cells is delayed, the study found.

Taken together, the data suggests that increased activity of duox in clownfish living in the giant carpet anemone result in higher levels of thyroid hormones, and thus the faster rate of white bar formation as iridophore pigment cells develop quicker.

However, the research raises still more questions for the scientists to answer, including the ecological reason for this variation in the rate of white bar formation.

It may be because the giant carpet anemone is more toxic, with thyroid hormone levels increasing as a response to stress, the researchers speculated.

"Here at OIST, we're starting to delve into some possible explanations," said Prof. Laudet. "We suspect that these changes in white bar formation are just the tip of the iceberg, and that many other differences are present that help the clownfish adapt to the two different sea anemone hosts."

CAPTION

During metamorphosis, the clownfish, Amphiprion percula, turns a vibrant orange and develops three white bars in succession, from head to tail. The rate at which the bars form depends on the sea anemone that the clownfish live in. Clownfish living in the long-tentacled anemone, Heteractis magnifica, (left) have fewer stripes than clownfish of the same age and size living in the shorter, carpet-style anemone, Stichodactyla gigantea (right). The image shows the typical appearance of clownfish aged 150-200 days.

CREDIT

Fiona Lee, Academia Sinica, Taiwan

CAPTION

Clownfish larvae treated with thyroid hormones formed a higher number of bands at an earlier stage of development, compared to control larvae that weren't treated with thyroid hormones. The image shows a control clownfish larvae (top) and a larvae five days after it was given a dose of thyroid hormones (bottom).

CREDIT

Pauline Salis, first author

USAGE RESTRICTIONS

Milky Way not unusual, astronomers find

Detailed cross-section of another galaxy reveals surprising similarities to our home

ARC CENTRE OF EXCELLENCE FOR ALL SKY ASTROPHYSICS IN 3D (ASTRO 3D)

Research News

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IMAGE: GALAXY UGC 10738, SEEN EDGE-ON THROUGH THE EUROPEAN SOUTHERN OBSERVATORY'S VERY LARGE TELESCOPE IN CHILE, REVEALING DISTINCT THICK AND THIN DISCS. view more 

CREDIT: JESSE VAN DE SANDE/EUROPEAN SOUTHERN OBSERVATORY

The first detailed cross-section of a galaxy broadly similar to the Milky Way, published today, reveals that our galaxy evolved gradually, instead of being the result of a violent mash-up. The finding throws the origin story of our home into doubt.

The galaxy, dubbed UGC 10738, turns out to have distinct 'thick' and 'thin' discs similar to those of the Milky Way. This suggests, contrary to previous theories, that such structures are not the result of a rare long-ago collision with a smaller galaxy. They appear to be the product of more peaceful change.

And that is a game-changer. It means that our spiral galaxy home isn't the product of a freak accident. Instead, it is typical.

The finding was made by a team led by Nicholas Scott and Jesse van de Sande, from Australia's ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) and the University of Sydney.

"Our observations indicate that the Milky Way's thin and thick discs didn't come about because of a gigantic mash-up, but a sort-of 'default' path of galaxy formation and evolution," said Dr Scott.

"From these results we think galaxies with the Milky Way's particular structures and properties could be described as the 'normal' ones."

This conclusion - published in The Astrophysical Journal Letters- has two profound implications.

"It was thought that the Milky Way's thin and thick discs formed after a rare violent merger, and so probably wouldn't be found in other spiral galaxies," said Dr Scott.

"Our research shows that's probably wrong, and it evolved 'naturally' without catastrophic interventions. This means Milky Way-type galaxies are probably very common.

"It also means we can use existing very detailed observations of the Milky Way as tools to better analyse much more distant galaxies which, for obvious reasons, we can't see as well."

The research shows that UGC 10738, like the Milky Way, has a thick disc consisting mainly of ancient stars - identified by their low ratio of iron to hydrogen and helium. Its thin disc stars are more recent and contain more metal.

(The Sun is a thin disc star and comprises about 1.5% elements heavier than helium. Thick disc stars have three to 10 times less.)

Although such discs have been previously observed in other galaxies, it was impossible to tell whether they hosted the same type of star distribution - and therefore similar origins. Scott, van de Sande and colleagues solved this problem by using the European Southern Observatory's Very Large Telescope in Chile to observe UGC 10738, situated 320 million light years away.

The galaxy is angled "edge on", so looking at it offered effectively a cross-section of its structure.

"Using an instrument called the multi-unit spectroscopic explorer, or MUSE, we were able to assess the metal ratios of the stars in its thick and thin discs," explained Dr van de Sande.

"They were pretty much the same as those in the Milky Way - ancient stars in the thick disc, younger stars in the thin one. We're looking at some other galaxies to make sure, but that's pretty strong evidence that the two galaxies evolved in the same way."

Dr Scott said UGC 10738's edge-on orientation meant it was simple to see which type of stars were in each disc.

"It's a bit like telling apart short people from tall people," he said. "It you try to do it from overhead it's impossible, but it if you look from the side it's relatively easy."

Co-author Professor Ken Freeman from the Australian National University said, "This is an important step forward in understanding how disk galaxies assembled long ago. We know a lot about how the Milky Way formed, but there was always the worry that the Milky Way is not a typical spiral galaxy. Now we can see that the Milky Way's formation is fairly typical of how other disk galaxies were assembled".

ASTRO 3D director, Professor Lisa Kewley, added: "This work shows how the Milky Way fits into the much bigger puzzle of how spiral galaxies formed across 13 billion years of cosmic time."

Other co-authors are based at Macquarie University in Australia and Germany's Max-Planck-Institut fur Extraterrestrische Physik.

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36 dwarf galaxies had simultaneous 'baby boom' of new stars

Surprising finding challenges current theories on how galaxies grow

RUTGERS UNIVERSITY

Research News

 

IMAGE: THREE DOZEN DWARF GALAXIES FAR FROM EACH OTHER HAD A SIMULTANEOUS "BABY BOOM " OF NEW STARS. view more 

CREDIT: RUTGERS UNIVERSITY-NEW BRUNSWICK

Three dozen dwarf galaxies far from each other had a simultaneous "baby boom" of new stars, an unexpected discovery that challenges current theories on how galaxies grow and may enhance our understanding of the universe.

Galaxies more than 1 million light-years apart should have completely independent lives in terms of when they give birth to new stars. But galaxies separated by up to 13 million light-years slowed down and then simultaneously accelerated their birth rate of stars, according to a Rutgers-led study published in the Astrophysical Journal.

"It appears that these galaxies are responding to a large-scale change in their environment in the same way a good economy can spur a baby boom," said lead author Charlotte Olsen, a doctoral student in the Department of Physics and Astronomy in the School of Arts and Sciences at Rutgers University-New Brunswick.

"We found that regardless of whether these galaxies were next-door neighbors or not, they stopped and then started forming new stars at the same time, as if they'd all influenced each other through some extra-galactic social network," said co-author Eric Gawiser, a professor in the Department of Physics and Astronomy.

The simultaneous decrease in the stellar birth rate in the 36 dwarf galaxies began 6 billion years ago, and the increase began 3 billion years ago. Understanding how galaxies evolve requires untangling the many processes that affect them over their lifetimes (billions of years). Star formation is one of the most fundamental processes. The stellar birth rate can increase when galaxies collide or interact, and galaxies can stop making new stars if the gas (mostly hydrogen) that makes stars is lost.

Star formation histories can paint a rich record of environmental conditions as a galaxy "grew up." Dwarf galaxies are the most common but least massive type of galaxies in the universe, and they are especially sensitive to the effects of their surrounding environment.

The 36 dwarf galaxies included a diverse array of environments at distances as far as 13 million light-years from the Milky Way. The environmental change the galaxies apparently responded to must be something that distributes fuel for galaxies very far apart. That could mean encountering a huge cloud of gas, for example, or a phenomenon in the universe we don't yet know about, according to Olsen.

The scientists used two methods to compare star formation histories. One uses light from individual stars within galaxies; the other uses the light of a whole galaxy, including a broad range of colors.

"The full impact of the discovery is not yet known as it remains to be seen how much our current models of galaxy growth need to be modified to understand this surprise," Gawiser said. "If the result cannot be explained within our current understanding of cosmology, that would be a huge implication, but we have to give the theorists a chance to read our paper and respond with their own research advances."

"The James Webb Space Telescope, scheduled to be launched by NASA this October, will be the ideal way to add that new data to find out just how far outwards from the Milky Way this 'baby boom' extended," Olsen added.

Rutgers co-authors include Professor Kristen B. W. McQuinn; Grace Telford, a postdoctoral associate; and Adam Broussard, a doctoral student. Scientists at the University of Toronto, the Harvard-Smithsonian Center for Astrophysics, Johns Hopkins University and NASA's Goddard Space Flight Center contributed to the study.

CAPTION

Rutgers' unexpected discovery challenges current theories on how galaxies grow and may enhance our understanding of the universe.

CREDIT

Rutgers University-New Brunswick

WHY YOU NEVER FORGET A FACE

The brain learns faces fastest in person

The brain signal linked to face familiarity is strongest after getting to know someone in-person

SOCIETY FOR NEUROSCIENCE

Research News

 

IMAGE: EXPERIMENTAL PARADIGM AND EEG ANALYSIS METHODS. view more 

CREDIT: AMBRUS ET AL., JNEUROSCI 2021

The neural representation of a familiar face strengthens faster when you see someone in person, according to a new study published in JNeurosci.

The brain loves faces -- there's even an interconnected network of brain areas dedicated to face-processing. Despite all the research on how the brain sees faces, little is known about how the neural representation of a face changes as it becomes familiar.

To track how familiarity brain signals change, Ambrus et al. measured participants' brain activity with EEG before and after getting to know different faces. Participants were exposed to faces in one of three ways: perceptual exposure (a sorting game), media exposure (watching a TV show), and in-person (chatting with lab members). A jolt of brain activity appeared on the EEG around 400 milliseconds after viewing a face; the strength of the signal was tied to the familiarity of the face. The type of exposure affected how much the signal changed: in-person exposure strengthened it the most, followed by media exposure. Perceptual exposure had very little impact on the familiarity signal. These results emphasize the importance of in-person interactions when getting to know new people.

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Paper title: Getting to Know You: Emerging Neural Representations During Face Familiarization

About JNeurosci

JNeurosci, the Society for Neuroscience's first journal, was launched in 1981 as a means to communicate the findings of the highest quality neuroscience research to the growing field. Today, the journal remains committed to publishing cutting-edge neuroscience that will have an immediate and lasting scientific impact, while responding to authors' changing publishing needs, representing breadth of the field and diversity in authorship.

About The Society for Neuroscience

The Society for Neuroscience is the world's largest organization of scientists and physicians devoted to understanding the brain and nervous system. The nonprofit organization, founded in 1969, now has nearly 37,000 members in more than 90 countries and over 130 chapters worldwide.