The largest map yet of the brain's planning area reads which genes are switched on in 6.3 million cells from 1,494 donated brains

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27 more stories on this beat.

Each with its own sources. None of these is a link to the story above.

1. 02

   Fiji declares an HIV emergency

   Fiji, a Pacific island nation of fewer than a million people, has declared a national emergency over HIV. [20] In a statement on 15 September, Fiji's government said it recorded more than 2,000 new cases in 2025, 16 times as many as in 2019. [20] It estimates one adult in 60 now has the virus. [20] The rise came with more drug injecting. [20] Health workers blame injected crystal meth, a strong stimulant, and bluetoothing: drawing blood after a hit and injecting it into another person. [21]

   Why it matters — Injecting someone else's blood passes on whatever viruses it carries, which is why workers in Fiji say people are sharing blood, not just needles. [21] UNAIDS, the United Nations' HIV programme, called Fiji's rise one of the sharpest in the world. [20]

2. 03

   Why weight-loss drugs fail some people

   GLP-1 drugs such as Wegovy copy a gut hormone and work mainly by making people feel full. [22][23] Nature reported on 24 September that 10 to 15 in every 100 users lose little or no weight. [22] In one study at the Mayo Clinic, a large US hospital and research centre, some people felt full after 140 calories while others needed more than 2,000. [23] Those who needed the most did worse on liraglutide, an older GLP-1 drug. [23] Among 27,885 research volunteers at 23andMe, one gene change added about 0.76 kg of weight loss per copy. [12]

   Why it matters — A Mayo Clinic doctor says patients who do not respond often see themselves as failures, though the cause may lie in their biology. [23] The Endocrine Society, a doctors' group, calls matching each person to the right drug largely an aim for now. [22]

3. 04

   A shingles vaccine linked to fewer heart problems

   Shingrix, the newer shingles vaccine, replaced an older one called Zostavax in the United States in late 2017. [24] Oxford researchers compared about 72,000 people aged 60 and over, vaccinated in the six months either side of the switch. [25] Over seven years, the Shingrix group was 9% less likely to develop heart disease, heart failure or a stroke. [24] Heart failure was 12% lower and heart disease from narrowed arteries 10% lower. [26] The study appeared in the journal Nature Medicine on 26 August. [24]

   Heart failure12%

   Heart disease10%

   All heart and stroke9%

   Why it matters — People did not choose which vaccine was on offer, so the comparison is less likely to be skewed by healthier people choosing to get vaccinated. [25] It is still not a trial, and first results from a Danish trial of about 162,000 people are expected in 2027. [25]

4. 05

   US health department asks about phone radiation

   In mid-September the US Department of Health and Human Services asked for stories from people who believe phones, Wi-Fi or wearables harmed them. [18] Health secretary Robert F. Kennedy Jr. announced it at a conference of Children's Health Defense, a group that has spread unfounded claims about vaccines. [18] In January the FDA, the US medicines regulator, removed web pages saying phone radio waves had not been linked to health problems, the Wall Street Journal reported. [27] Twelve reviews commissioned by the WHO found no or very small effects on cancer below safety limits. [18]

   Why it matters — Radio waves from phones are too weak to break DNA, which is how X-rays can cause cancer. [18] A bioengineer told the magazine Scientific American that personal stories cannot show whether devices cause harm, while a careful review of all the evidence can. [18]

5. 06

   An online course cut new anxiety and depression

   A trial took 566 adults who had some anxiety or low mood but no diagnosed disorder. [17] Two groups got an eight-session online course based on cognitive behavioural therapy, a talking therapy: one with a personal guide, one with automatic messages. [17] A third group waited. [17] Within a year, 19.4% of the guided group and 14.8% of the automated group developed an anxiety or depressive disorder, against 30.9% of those waiting. [17] It was published in October 2025. [17]

   Guided course19.4%

   Automated course14.8%

   Waiting list30.9%

   Why it matters — These people had symptoms but no disorder yet, so the course was tested as prevention, not treatment. [17] For every six to eight people who took it, one fewer developed a disorder within the year. [17]

6. 07

   Sleep therapy eased depression for a year

   Cognitive behavioural therapy for insomnia, or CBT-I, is a talking therapy aimed at sleep. [28] A 2026 review in the journal Sleep Medicine Reviews pooled 53 reports covering 13,608 adults with insomnia. [28] The therapy lowered depression symptoms more than control groups did at 3, 6 and 12 months after it ended. [28] The effect was modest and shrank over the year. [28] A small trial found four video-call sessions during the pandemic improved both sleep and mood over 28 weeks. [29]

   Why it matters — Insomnia and depression often come together. [28] Treating the sleep problem also eased the low mood, and the gain lasted a year, though it got smaller. [28]

7. 08

   A rare gene tied to lung cancer in non-smokers

   Between 15 and 25 in every 100 lung cancers are in people who never smoked, depending on the region. [30] A study in the journal Science, reported on 17 September, found a very rare gene change linked to 25 times the odds of lung cancer in never-smokers. [13] In the US the change is far more common in Southern Appalachia, a mountain region in the east. [13] The team used genetic data from 23andMe. [13]

   Never smoked43%

   Smoked11%

   Why it matters — Experts said the change probably explains only a small share of these cancers. [13] Lung cancers in never-smokers often carry different gene changes from smokers' cancers: EGFR, which some targeted drugs act on, turns up in 43% against 11%. [31]

8. 09

   When antibodies look like psychosis

   In anti-NMDA receptor encephalitis, the immune system makes antibodies against a receptor that brain cells use to pass signals. [9] It can look like a psychiatric illness at first. [32] A 2025 case report describes a 26-year-old woman whose sudden psychiatric symptoms led to a coma. [32] Doctors found a tumour on her ovary, and after immune treatment and surgery to remove it she slowly recovered. [32]

   Why it matters — A review published in October 2025 says the evidence for a separate illness called autoimmune psychosis is still lacking. [9] It also warns that antibody tests are being ordered widely in psychiatric patients, with little thought about who is likely to have the disease. [9]

9. 10

   High inflammation marks some schizophrenia brains

   Researchers examined the midbrain, a small region deep in the brain, in donated brains from 63 people with schizophrenia, 33 with bipolar disorder and 61 with neither. [10] They sorted the brains into high- and low-inflammation groups. [10] In the high-inflammation group, genes for TNF, an immune signal, and its receptors were among the most changed, mostly in support cells. [10] A separate 2026 study of 49 people at high risk of psychosis found their immune signals and complement, a set of blood proteins that fight infection, differed from healthy peers. [33]

   Why it matters — The first study was published in November 2025. [10] Its authors say drugs that block TNF should now be tested in patients who show high inflammation. [10]

10. 11

    101 schizophrenia genes, 15 already hit by drugs

    Genetic studies have found more than 250 places in DNA linked to schizophrenia. [34] A team combined several methods on data from 67,390 people with schizophrenia and 94,015 without. [34] It picked out 101 genes, and 15 of them are already targeted by approved or experimental drugs. [34] Seven of those 15 have never been tested in trials for any psychiatric illness. [34] The study was published in the journal Translational Psychiatry in February. [34]

    Why it matters — Drugs that already exist could be tried for schizophrenia, rather than starting from nothing, the authors say. [34]

11. 12

    Problem social media use, then more ADHD signs

    Researchers led from the University of California, San Francisco followed 11,286 US young people through five yearly check-ins. [15] When a teenager's social media use became more problematic, their parents reported more symptoms of ADHD, a condition of attention and impulse control, a year later. [15] Problem use means signs such as trying and failing to cut down. [35] The link held for boys but not for girls. [15] The study was published in the journal JAMA Network Open in July. [15]

    Why it matters — The study compared each young person with themselves over time, which earlier one-off surveys could not. [15] It still shows a link, not proof that the apps cause the symptoms. [15]

12. 13

    US government warns about children's screens

    On 20 May the US health department published a surgeon general advisory saying too much screen time harms children's health. [19] The country had no confirmed surgeon general at the time. [19] The advisory says US children start watching screens before age one, and teenagers often spend more time on screens than at school. [19] Advisories are not rules; they are guidance for lawmakers. [19]

    Why it matters — Some experts say blanket limits may not fix the problems the advisory names, because scrolling social media and doing a school project on a screen are very different. [19]

13. 14

    About an hour a day on phones at school

    A short report published in February in JAMA, a US medical journal, measured phone use by 640 US teenagers, average age 15, with an app on their phones. [14] They spent an average of 1.16 hours on their phones during school hours. [14] Social media took the most time, about 30 minutes. [14] Video apps and games took about 15 minutes each. [14] Older teens and those from lower-income homes used their phones more at school. [14]

    Social media30 minutes

    Video apps15 minutes

    Games15 minutes

    Why it matters — More schools are banning or limiting phones. [19] Its figures came from an app on each phone, not from what teenagers remembered. [14]

14. 15

    Parents' screen habits show up in teens

    A study of 7,947 US adolescents, average age 12.9, compared family screen rules with the children's screen use a year later. [36] Using screens as a reward or punishment, and screens in the bedroom, went with more screen and phone time. [36] Parents who used a lot of screens themselves, or kept screens on at meals, had children who used them more. [36] Parents who watched and limited screen time had children who used them less. [36]

    Why it matters — It was published in June and shows links, not causes. [36] It fits a 2024 finding from the same study that family conflict went with more screen time and closer parental watching with less. [37]

15. 16

    More social media, lower memory scores

    Researchers followed 7,528 US children aged 8 to 13 for two years. [38] Children whose social media use was high and climbing scored lower on memory tests two years later than children who used little or none. [38] Even low but rising use went with lower scores on some tests. [38] The study was published in March. [38]

    Why it matters — It checked the children's memory at the start and allowed for it, so the lower scores came after the change in use. [38] It still shows a link over time, not proof that social media caused the drop. [38]

16. 17

    Social media time and trying cannabis

    A study of 7,691 US adolescents, average age 12, compared daily social media time with cannabis use two years later. [39] More social media time went with a higher chance of having tried cannabis. [39] Part of the link ran through beliefs: teenagers who expected cannabis to feel good were more likely to try it. [39] Those expectations explained about a fifth of the link. [39] The study was published in October 2025. [39]

    Why it matters — Cannabis is the third most used drug among US teenagers, after alcohol and tobacco. [39] The study allowed for friends' cannabis use, which could otherwise explain both habits. [39]

17. 18

    Boys who think they are too small

    Muscle dysmorphia is a condition in which a person believes their body is too small or not muscular enough. [40] A review published in late 2025 gathered what is known about it in adolescents and young adults. [40] It says the condition is increasingly recognised in boys and young men, as ideals shift toward a lean, muscular body. [40] One study found 1.8% of 3,618 Australian adolescents met strict criteria. [40] Another found 17.2% of 2,256 young Canadians at clinical risk. [40]

    Why it matters — The review says treatment evidence in large groups of young people is still scarce. [40] It notes that programmes to prevent eating disorders may also reduce these symptoms. [40]

18. 19

    Sleep therapy by app works across 49 trials

    A 2025 review pooled 49 trials with 20,118 adults testing fully automated digital CBT-I, sleep therapy given by an app or website with no therapist. [16] It lowered insomnia severity scores by about 3.4 points more than control groups. [16] The effect was larger in studies that used strict rules for diagnosing insomnia. [16] A small trial of online sessions in 40 people with type 2 diabetes found no difference in the main sleep score. [41]

    Why it matters — Results varied hugely between studies, which the authors flag. [16] The diabetes trial did find more regular sleep, and less anxiety two months after the sessions ended. [41]

19. 20

    No germ link in 940 lung cancers

    Interest has grown in whether germs living in tissue play a part in cancer. [42] The Sherlock-Lung study looked for germs in 940 lung cancers from people who never smoked, using three detection methods. [42] It found very few bacteria. [42] It found no consistent link between the lung's germs and age, sex, ancestry, second-hand smoke, cancer stage or survival. [42] It was published in the journal Nature Communications in December 2025. [42]

    Why it matters — Earlier studies on lung tissue were small. [42] The authors say any null result could change if better ways of detecting germs arrive. [42]

20. 21

    Blocking one immune protein protected mice

    Researchers studied mice with anti-NMDA receptor encephalitis, the antibody disease of the brain. [11] The antibodies made microglia, the brain's own immune cells, produce more of a protein called C1q. [11] Patients with the disease also had raised C1q in the fluid around the brain and spine. [11] In the mice, an antibody that neutralised C1q reduced the damage. [11] The work appeared in the journal Molecular Therapy in November 2025. [11]

    Why it matters — This is mouse work, and no patient has been treated this way. [11] The authors say C1q could become a target for treatment. [11]

21. 22

    Weight-loss drugs spared most muscle

    A study in the journal Cell Reports Medicine in March tested a common worry: that GLP-1 drugs strip muscle along with fat. [43] In obese mice the drugs mostly removed fat, and the liver shrank more than muscle did. [43] Muscle mass and strength fell slightly, but muscle relative to body size improved and the mice ran better. [43] In middle-aged men on the drugs, body make-up improved without a loss of strength. [43]

    Why it matters — The human part was a small early trial that the authors call a proof of concept. [43]

22. 23

    A daily weight-loss pill in a Chinese trial

    HRS-7535 is an experimental daily pill that acts on the same receptor as GLP-1 injections. [44] A trial at 29 centres in China gave it or a dummy pill to 235 adults with obesity but not diabetes. [44] After 26 weeks, people on the highest dose lost 9.36% of their body weight, against 2.50% on the dummy pill. [44] Stomach and gut side effects were the most common. [44] The results were published in June. [44]

    Why it matters — The lowest dose did no better than the dummy pill, so the dose mattered. [44]

23. 24

    Weight-loss drugs and eating disorders

    NPR, a US public radio network, reported in February on people with eating disorders who take GLP-1 drugs. [45] One man it followed has anorexia and still takes a monthly shot, fearing he will regain weight if he stops. [45] Nearly one person in ten meets the medical definition of an eating disorder during their life. [45] The drugs are easy to get online with little screening. [45]

    Why it matters — Very little is known about how the drugs affect people who binge or restrict food, NPR found. [45]

24. 25

    Long COVID and mental health in Johannesburg

    A study in Johannesburg, South Africa, compared 360 adults by how COVID-19 had affected them: no symptoms, symptoms, hospital, or vaccinated comparison. [46] Rates of post-traumatic stress disorder (21.1%) and of distressing physical symptoms (22.9%) were high. [46] People who had COVID-19 with symptoms had the most depression, anxiety and suicidal thoughts. [46] Worse long COVID went with worse mental health. [46]

    Why it matters — It was published in July. [46] Little is known about long COVID's mental effects in sub-Saharan Africa, the authors say, and this study adds data from Johannesburg. [46]

25. 26

    Bad sleep, less effort for rewards

    Researchers tested 101 adults, average age 23, once a week for six weeks. [47] Each week they rated their insomnia and depression and did a task measuring how hard they would work for a reward. [47] Among those with more depression symptoms, a week of worse insomnia predicted less effort for rewards the next week. [47] The study was published in January. [47]

    Why it matters — Sleep problems and a loss of drive for rewards are both tied to depression starting and lasting. [47] This links the two week by week in the same people. [47]

26. 27

    Thinking tests after online sleep therapy

    Two trials gave 170 people sleep therapy over the internet for 9 or 12 weeks. [48] Some had insomnia alone and some had insomnia with depression. [48] Before and after, 124 of them took computer tests of attention, planning and emotional reactions. [48] Scores improved on 7 of the 17 measures. [48] Having depression made little difference to most scores. [48]

    Why it matters — People with insomnia often report that their thinking suffers, but tests had rarely checked it. [48] It was published in September 2025. [48]

27. 28

    A herbal capsule added little on the main test

    A trial gave 60 people with insomnia and depression symptoms zolpidem, a common sleeping pill. [49] Half also got Shugan Jieyu capsules, a herbal medicine, and half a dummy capsule. [49] After eight weeks both groups improved on sleep, anxiety and mood scores. [49] On the main insomnia score the groups did not differ. [49] On overnight sleep tests, the herbal group slept longer and woke less. [49]

    Why it matters — Both groups got the sleeping pill, so most of the improvement cannot be credited to the capsule. [49] It was published in October 2025. [49]