Neural circuitry that can make it difficult to start a difficult task

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In response to US President Donald Trump’s threats to somehow seize Greenland (Kalalit Nunat), American scientists have drafted what they call a statement of solidarity with the island, which is open to any US-based researchers who have conducted research there. “A lot of people in the United States — not just scientists — are very upset by the rhetoric toward Greenland,” says paleoclimatologist Yarrow Ackford, one of the initiative’s founders. “But the scientists who work there feel it very personally.” “We want to let our colleagues and friends in Greenland know that we are thinking of them now, and that we stand with them.”

Nature | 6 minutes read

Read more: British glaciologist Martin Siegert wrote that Greenland is indispensable to global climate science (Conversation | 7 minutes read)

Scientists have identified a neural circuit that appears to act as a “motivation brake,” inhibiting the motivation to begin a difficult or unpleasant task. When the team selectively suppressed this circuit in macaques (Macaque foscata), animals were more willing to initiate a potentially unpleasant action. If these findings are confirmed in humans, they could change the way doctors deal with the debilitating lack of motivation associated with depression. But any relief from stimulus suppression will require care to prevent unintentional fatigue and exhaustion, says neuroscientist and study co-author Ken-ichi Amemori.

Nature | 5 minute read

reference: Current biology paper

Last week, the US Congress published a spending bill that would effectively eliminate NASA’s Mars Sample Return (MSR) program, which was supposed to transport Martian material collected by the Perseverance rover to Earth. Among the MSR projects halted by the bill is a chemical analysis of a rock sample containing compounds that could be a signature of ancient microbial life. There may be other ways to get samples to Earth, such as involving private airlines, but “the program — as we know it — is dead,” says Casey Dreyer, head of space policy at the Planetary Society, a non-profit organization.

Nature | 5 minute read

Common macrolanguage models often reproduce harmful stereotypes about Indian castes, genetic groups traditionally associated with specific occupations and social status. The researchers used a tool specifically designed to detect “class bias” in MBAs, and found that every model they tested showed some bias. GPT-4o and GPT-3.5, created by OpenAI, had some of the highest bias scores. Information about minority groups may be less likely to appear in prestigious journals or other outlets, and may be written in local languages, which could result in it being excluded from AI training data, says Agrima Seth, who studies cultural biases in MBAs.

Nature | 5 minute read

Reference: arXiv Preliminary edition 1, Pre-printing 2 & Pre-printing 3 (Not peer-reviewed)

Features and opinion

Anxiety, depression, suicidal ideation and self-harm have increased among college students in the past decade, note mental health researchers Lauro Miranda Demenic and Anne Duffy. However, globally, only a small fraction of students who might benefit from assistance receive it – with inequalities for disadvantaged and at-risk groups. Deminick and Duffy advise universities on how to effectively use scarce resources to best support students in their care – such as mental health literacy courses that count towards qualifications.

Nature | 10 minute read

Its founder Jimmy Wales says the success of Wikipedia, an online encyclopedia written by volunteers, is built on trust, and he hopes to apply this approach to a new form of social media that aims to prioritize trustworthy content. “We have a lot of experience with people who disagree on a fundamental issue, but can come together to work productively,” Wells says. “We still have to take engagement into account, because no one will use the platform if it’s boring. But can we reward people for creating thoughtful dialogue?”

Nature | 11 minute read

Former academics who have diversified into agriculture, launched their own businesses, joined a non-profit organization or pursued independent research say there is life after academia. “Now is the time to be bold, brave, and embrace your emotions,” says immunologist Luz Cumba Garcia, who lost her job in global health in the US and is now a self-employed policy consultant.

Nature | 13 minute read

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Food scientist Raquel Gomez-Plego hopes to make the famous tortilla even better. “The tortilla ingredients I was frying in this photo have been fermented to include probiotics and prebiotics for gut health,” she says. “Improving the staple food people eat every day is a powerful public health strategy.”

On Friday, Leif Bengwenson visited the Barwon River in Australia. And Lev was not alone! There was also a feathered friend in the photo: the sky-blue kingfisher (Alcido Azuria). Did you find the penguin (and the kingfisher)? When you are ready, Here’s the answer.

Thanks for reading,

Flora Graham is senior editor at Nature Briving

With contributions by Jacob Smith

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