#PNASNexus
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jayvanbavel.bsky.social
Expressions of blatantly immoral actions about outgroup members are growing on social media

This leads people to radically overestimate the degree to which political outgroup members support immoral actions

Democrats and Republicans are both off in their estimates. academic.oup.com/pnasnexus/ar...
November 10, 2025 at 10:11 PM
matthewfacciani.bsky.social
New analysis of neuroimaging data finds that messages that activate the brain’s reward and social-relevance systems are more persuasive, influencing both individuals and large groups beyond what people say they like via self-reports.
academic.oup.com/pnasnexus/ar...
Brain activity explains message effectiveness: A mega-analysis of 16 neuroimaging studies
Abstract. Persuasive communication in marketing, political, and health domains influences sales, elections, and public health. We present a mega-analysis (
academic.oup.com
November 10, 2025 at 3:31 PM
jayvanbavel.bsky.social
For each additional moral–emotional word in a social media post, the number of shares increases 13%

Our new meta-analysis finds robust evidence of moral contagion (N=4,821,006)

The moral contagion effect is even stronger in larger, pre-registered studies (17%).
academic.oup.com/pnasnexus/ar...
November 5, 2025 at 4:58 PM
jayvanbavel.bsky.social
This meta-analysis on moral contagion was led by @williambrady.bsky.social @steverathje.bsky.social and Laura Globig academic.oup.com/pnasnexus/ar...
Estimating the effect size of moral contagion in online networks: A pre-registered replication and meta-analysis
Abstract. Over 5 billion people now use social media platforms. As our social lives become increasingly entangled with online social networks, it is import
academic.oup.com
November 5, 2025 at 5:14 PM
cgsunit.bsky.social
I keep coming back to @nsousanis.bsky.social's way of talking through the value of learning. I love this thread where we get to see some of the student response!

Also, it reminds me of a recent paper that talks through that lack of friction leading to less learning: academic.oup.com/pnasnexus/ar...
nsousanis.bsky.social Nick Sousanis @nsousanis.bsky.social · Aug 24
My statement on Ai from the mini-comic as syllabus i made for new class I'm teaching that starts tomorrow! It robs you of your decisions & struggles - and the joy of being surprised. We won’t to be robbed of our learning - this is essential. This & the full mini at post:
bsky.app/profile/nsou...
October 31, 2025 at 12:39 AM
drjoehanson.bsky.social
When people learn with ChatGPT instead of following their own searches, they end up knowing less, caring less, and producing worse advice, even when the facts are the same.

Friction is an essential ingredient for learning! Convenience makes us shallow.

academic.oup.com/pnasnexus/ar...
Experimental evidence of the effects of large language models versus web search on depth of learning
Abstract. The effects of using large language models (LLMs) versus traditional web search on depth of learning are explored. A theory is proposed that when
academic.oup.com
October 28, 2025 at 3:14 PM
mugrimm.bsky.social
academic.oup.com/pnasnexus/ar...
Implications, limitations, and future research Recent years have witnessed a growing philosophical debate over the risks of AI use, such as the possibility that increased reliance on AI will diminish humans' ability to complete tasks themselves (41-43). While this has always been a possible byproduct of technological advancement (44), some argue that the deskilling that could arise from Al use will be especially pernicious by degrading basic thinking and reasoning skills over time (43, 45). Consistent with this, recent findings have shown, for example, that the use of Al as an aid can constrain the range of creative solutions to specific problems (46). Nevertheless, whether Al use can have such far-reaching effects remains an open empirical question. Our work contributes to this debate by offering experimental evidence of the effects of Al in the context of learning and advice formation. We find that unlike learning from web search, which requires one to comprehend, interpret, and integrate information for oneself, learning from presynthesized LLM results can lead to the development of shallower knowledge on a subject. Hence, it is possible that increased reliance on LLM syntheses for learning in lieu of standard web search, especially among younger people, threatens to "deskill" the ability to engage in active learning-a critical ingredient in knowledge development (9, 33). That said, our findings naturally come with important caveats. For one, although participants in most of our experiments interacted with actual LLMs (e.g. GPT-40) and web search tools (Google), the results arose in the context of a specific experimental task: that of learning about a topic with the intention to share advice on it with others. While we argue that this is a common use case for LLMs, different applications of LLMS may naturally yield different results. For example, there would presumably be no obvious advantage to using traditional web search (vs. LLMs) if one's goal is simply t
October 28, 2025 at 10:04 PM
veraaldeias.bsky.social
📄 New paper 📣 of @matrixerc.bsky.social & @welkergroup.bsky.social! We show that microstratigraphic-scale #paleoproteomics works in intact sediments - opening new ways to explore ancient ecosystems & hominin behaviour 🌍🦴
@erc.europa.eu @icarehb.bsky.social 🔗 academic.oup.com/pnasnexus/ar...
New methods on the block: Taxonomic identification of archaeological bones in resin-embedded sediments through paleoproteomics
Abstract. The integration of biomolecular studies of past organisms with geoarchaeological studies can significantly improve our understanding of the relat
academic.oup.com
October 14, 2025 at 10:28 AM
matthewfacciani.bsky.social
For years, we've seen platforms devolve more into echo chambers themselves, and Musk's Twitter acquisition only accelerated this trend.
academic.oup.com/pnasnexus/ar...
Ideological fragmentation of the social media ecosystem: From echo chambers to echo platforms
Abstract. The entertainment-driven nature of social media encourages users to engage with like-minded individuals and consume content aligned with their be
academic.oup.com
October 13, 2025 at 4:45 PM
jayvanbavel.bsky.social
We have gone from "echo chambers" to "echo platforms"
Users migrate between platforms in search of environments aligned with their preferences

A new paper analyzes 117 million posts from the 2020 US elections from 9 social media platforms and finds big differences
academic.oup.com/pnasnexus/ar...
October 13, 2025 at 3:58 PM
katymilkman.bsky.social
🚨NEW PAPER ALERT🚨
Can reminder emails compel Americans to save? We ran a 2 million person megastudy with a large US bank to find out. Our results published today in @pnasnexus.org suggest that the answer is: yes, probably, a little. 🧵
👀 the paper: academic.oup.com/pnasnexus/ar...
September 30, 2025 at 10:29 PM
dpcarrington.bsky.social
New research: #airpollution linked to worse eyesight in children

academic.oup.com/pnasnexus/ar...
Benefits of clean air for school children's vision health
Abstract. Myopia has become a significant public health concern among school-aged children in East Asia. A growing body of evidence acknowledges the multif
academic.oup.com
September 24, 2025 at 1:21 PM
al-ka.bsky.social
Restorative justice appeals trump retributive vigilance on social media url: academic.oup.com/pnasnexus/ar...
Restorative justice appeals trump retributive vigilance on social media
Abstract. Human beings have a powerful urge to confront wrongdoing and reestablish justice. In online spaces, this typically takes the form of vigilante-li
academic.oup.com
September 17, 2025 at 9:46 PM
drsarahmyers.bsky.social
New research with Mhairi Gibson, Eshetu Gurmu, @alexalvergne.bsky.social @danielredhead.bsky.social & Arsi Oromo participants! @bristolantharch.bsky.social @mpi-eva-leipzig.bsky.social academic.oup.com/pnasnexus/ad...
Gender-biased clustering of attitudes towards physical intimate partner violence: A social network analysis in south-central Ethiopia
Abstract. Changing social norms, shared beliefs about what is acceptable, is a key focus of global health campaigns aimed at ending intimate partner violen
academic.oup.com
September 17, 2025 at 2:26 PM
pnasnexus.org
A Dutch study explores a key barrier to social integration: strong in-group preferences. One hopeful exception: young people don’t have strong preferences for people of their own ethnicity when it comes to sports activities. In PNAS Nexus: academic.oup.com/pnasnexus/ar...
Street soccer championship in The Hague, Netherlands, 2010.
September 17, 2025 at 5:05 PM
pnasnexus.org
Sediment cores retrieved by ROVs show barrels dumped off the coast of California 50 years ago were likely filled with alkaline waste—and have created new microbial ecosystems, similar to those found around hydrothermal vents. In PNAS Nexus: academic.oup.com/pnasnexus/ar...
Pushcore sampling from the white halo close to a barrel by using the ROV manipulator arm. CREDIT: Schmidt Ocean Institute
September 17, 2025 at 5:05 PM
haneuljang.bsky.social
💙New paper!💙

How is knowledge transmitted across generations in a foraging society?

With @danielredhead.bsky.social
we found: In BaYaka foragers, long-term skills pass in smaller, sparser networks, while short-term food info circulates broadly & reciprocally

academic.oup.com/pnasnexus/ar...
Transmission networks of long-term and short-term knowledge in a foraging society
Abstract. Cultural transmission across generations is key to cumulative cultural evolution. While several mechanisms—such as vertical, horizontal, and obli
academic.oup.com
September 14, 2025 at 7:52 AM
stubutchart.bsky.social
More evidence of the scale of human impacts: new study documents 220 extinctions (incl. 27 birds) on Macaronesia (Azores, Madeira, Canaries, Cape Verde etc). Post-human colonisation extinction rate >12 times higher. Paper doi.org/10.1093/pnasnexus/pgaf215. Story: www.birdguides.com/articles/ext...
A synthesis of terrestrial species extinctions in the Macaronesian Islands and their correspondence with human occupancy
Abstract. We present the first synthesis of all known terrestrial endemic species extinctions in the biogeographical region of Macaronesia, covering all ar
doi.org
September 12, 2025 at 9:52 AM
pnasnexus.org
City babies were weaned earlier than babies in less complex settlements in the Roman Empire, according to a study of adult teeth. Urbanites were following contemporary medical advice; ancient Roman medical experts urged weaning by age two. In PNAS Nexus: academic.oup.com/pnasnexus/ar...
Infant sarcophagus inscribed, in Latin, “Marcus Cornelius Statius, son of Marcus, of the tribe Palatina.” The carving depicts a person nursing a baby. Made around 150–160 CE and possibly found in Ostia Antica, Italy. CREDIT: Musée du Louvre
January 23, 2025 at 2:49 PM
jvipondmd.bsky.social
“The prevented fraction associated with mask mandates was 46% (95% CI 41%-51%), with 290,000 clinical cases, 3008 deaths, and loss of 29,038 QALY averted from June to December 2020, representing $CDN 610 million in economic wealth.” academic.oup.com/pnasnexus/ad...
Impact of community mask mandates on SARS-CoV-2 transmission in Ontario after adjustment for differential testing by age and sex
AbstractBackground. Mask use for prevention of respiratory infectious disease transmission is not new, but has proven controversial during the SARS-CoV-2 pandem
academic.oup.com
February 12, 2024 at 10:51 PM
reutavinun.bsky.social
2/
The study had two groups. One kept using their phones.
The other had internet access blocked on their phones for two weeks.
They could still use WiFi on other devices.
Screen time halved.
academic.oup.com/pnasnexus/ar...
Blocking mobile internet on smartphones improves sustained attention, mental health, and subjective well-being
Abstract. Smartphones enable people to access the online world from anywhere at any time. Despite the benefits of this technology, there is growing concern
academic.oup.com
May 7, 2025 at 8:35 AM
mielcarz.bsky.social
Likely this one, but I 100% agree they should include the link: academic.oup.com/pnasnexus/ar...
Blocking mobile internet on smartphones improves sustained attention, mental health, and subjective well-being
Abstract. Smartphones enable people to access the online world from anywhere at any time. Despite the benefits of this technology, there is growing concern
academic.oup.com
May 13, 2025 at 10:53 AM
pnasnexus.org
An experimental rig simulating the cuff-based blood pressure test used in medical settings around the world allows researchers to probe the physics behind why systolic pressure readings are systematically underestimated. In PNAS Nexus: academic.oup.com/pnasnexus/ar...
Image of the artery model under the compressive blood pressure cuff in the experimental rig.
August 21, 2025 at 4:18 PM
ecurry1956.bsky.social
academic.oup.com/pnasnexus/ar... 7/8
December 10, 2024 at 12:45 PM