Nature Neuroscience, Published online: 08 May 2026; doi:10.1038/s41593-026-02305-0
The choreography of cerebral vasculature development
Nature Neuroscience, Published online: 08 May 2026; doi:10.1038/s41593-026-02305-0
The choreography of cerebral vasculature development
Nature Neuroscience, Published online: 08 May 2026; doi:10.1038/s41593-026-02304-1
Neurons for seeing and imagining
You may have a memory of being separated from a parent when you were a child, even just for a few minutes. Maybe you lost them in a crowd or wandered a little too far at the store and felt panicked and afraid.
A moment like this might be among your earliest memories because the feeling was so intense, says Caitlyn Downie, LCSW, the Director of Trauma and Resilience at the Child Mind Institute. That offers some insight into the fear of a child of any age who is separated from a parent or caregiver in a more serious way. The effects of this stress are so powerful they can actually change the way a child develops.
A toddler whose mother goes to prison. A kindergartener whose father is detained and deported. A teen who is placed in foster care. These are a few examples of what experts call traumatic separation, a clinical concept based on the importance of the parent-child bond and the profound effects that can result from breaking it.
Traumatic separation isn’t a clinical diagnosis, but research shows that it can be profoundly harmful to kids. What makes it traumatic (as opposed to routine partings, like when an adult regularly leaves their child to go to work) is the character of the separation: ones that are sudden, unexpected, or confusing, or those that come about through larger distressing events, like a natural disaster or war. It’s not defined by the time spent apart — both short and long-term separations can be harmful.
Some common examples of separation that can become traumatic include:
Separating from a parent or primary caregiver can be distressing to a child even when it’s deemed necessary for their safety, as in cases where the parent they have been separated from has abused them, says Kimberly Alexander, PsyD, a psychologist at the Child Mind Institute. “There’s still a natural attachment that occurs. And the separation disrupts that relationship, even if it’s for the support and care of the child.”
More than eight decades of research has shown the profound developmental importance of the parent-child bond. This is the guiding principle of attachment theory, which was pioneered by a British psychologist who studied children who were evacuated during the Blitz, the aerial bombardment of London in World War II.
Here’s what the research tells us about the harms of traumatic separation:
Think of secure attachment as a “fundamental sense of security and safety” that a child feels with a parent or caregiver, says Dylan Gee, PhD, a psychologist at Yale University who studies how early-life stress affects children’s development.
“Attachment is the lens through which children come to know what they can expect from the world around them,” she explains. “Is this going to be a safe place or a dangerous place? This is foundational to a child’s sense of their ability to navigate the world. Traumatic separation can shatter that sense of safety.”
Children’s brains are especially plastic, says Dr. Gee, constantly learning to understand their environment and how to deal with stress. “Trauma that occurs in childhood can be even more consequential than trauma that occurs later in life,” she says, and experiencing these disruptions in childhood can affect the way your brain and body are primed to react to stress later on.
But heightened plasticity is a paradox, she adds. “It confers more vulnerability, but it also confers more potential for resilience — children have heightened potential for supportive intervention and for healing and recovery.”
There are acute and short-term effects that are common across kids of all ages:
Sleep problems: “It’s often one of the first things that we see: nightmares, trouble falling asleep, or a lot of crying as kids are trying to fall asleep,” Dr. Gee says.
Separation anxiety: This might look like distraction, withdrawal, or clinginess because of fear of being separated from their new caregivers, Dr. Alexander says.
But signs may take weeks or months to show up. Dr. Alexander advises caregivers to consider the child’s baseline — their typical patterns of eating, sleeping, or engaging with others. “If they’re having more trouble with sleep, they’re eating more, eating less, they’re withdrawing or expressing a lot of worried thoughts three or four months later — that’s something worth getting looked at by a clinician,” she says.
“Sometimes people ask, ‘Well, when is separation the most harmful?’ It can be extremely harmful at any age,” Dr. Gee emphasizes. But there are specific signs at different developmental stages:
Babies may not be as consciously aware of being separated from a parent as older children, “but they’re fundamentally aware that their primary source of regulation and safety is missing,” Dr. Gee says. Because infants are so reliant on caregivers for nurturing and sustenance, the separation “can be experienced as a threat to their survival.” That might look like “crying a lot or becoming withdrawn,” she says. “And at any age we can see intense fear.”
Toddlers and young children might become extra clingy with new caregivers or show regressive behaviors like bedwetting or baby talk. Regressive behaviors happen when kids are overwhelmed by stress and can’t express themselves another way, Downie says. “It’s like your nervous system goes kind of haywire,” she explains, “so it uses the body to signal that something is wrong.”
Similarly, kids at this age might act out more, throwing more tantrums, or withdraw. They might develop selective mutism, a condition where kids are too anxious or distressed to speak, even when they want to, in certain situations or with certain people.
School-age children might act out or experience separation anxiety. They may also struggle to understand the meaning of the separation, why it happened, or who is at fault for it. Thus, kids at this age are more prone to magical or distorted thinking and feelings of guilt, thinking or saying things like, “I’m the one that caused this” or “This is my fault.”
The weight of these distorted thoughts or other worries, Dr. Alexander says, might make it appear as though a child is struggling to concentrate or that they’re disengaged or distracted. They might withdraw in a group or be averse to stepping outside of their comfort zone.
Children who are school age or older can also experience emotional desensitization — a kind of emptiness of feeling — Downie says, which can look like spikes in irritability, a lack of empathy, not smiling or expressing positive emotions, or an inability to relate to others.
“I’ve seen teenagers have a lot of mistrust with systems and be very oppositional,” says Downie. “Like, ‘I don’t trust you. I don’t trust my teacher. I don’t trust this child services worker.’” It might make sense that, say, a teen in foster care would be wary of the foster care system. But Downie says it’s often a larger instinct for anger and mistrust, one that extends beyond any specific entity or person.
The teenage years are also when kids are forming their identity, and traumatic separation can fundamentally alter that process. For example, a teen with younger siblings may step into a parent role, taking on new worries and responsibilities. Conversely, teens may become more reckless in a caregiver’s absence, putting them at risk for substance abuse or incarceration.
Adults caring for a child who has been separated from a parent — family members, foster parents, teachers — “can play a profound role in supporting their mental health and resilience,” says Dr. Gee.
One of the most important things caregivers can do is be present as a child reacts to their experiences, especially if and when scary feelings come up. But be careful not to lead kids or assume they feel a certain way. “You don’t want to make something more distressing to a child if it’s not presenting itself,” says Downie.
If a child expresses guilt, or says something like, “This is my fault,” there are still ways to validate the feeling without endorsing the statement, says Dr. Alexander. You might say something like: “I can understand why that thought comes to mind and how difficult it is to feel that way. When you’re ready, let’s think about other possibilities to this situation.”
One of the hardest things about traumatic separation is the uncertainty — Where did they go? When will they come back? What is happening? Giving kids some sense of consistency and stability can help them feel safe despite the unknowns. So as much as possible, help them stick to any routines: going to school, seeing friends, doing activities they enjoy.
Dr. Alexander advises focusing on things you can control — for example, shielding kids from potentially worrying discussions in a family where a parent has been deported.
“There would likely be a lot of conversations in the home about the situation, maybe a lot of watching the news, maybe making a lot of phone calls to attorneys,” she explains. “So where are you having those conversations, and can you have them in an area or at a time of day where your kid isn’t overhearing the discussions out of context?”
For young kids, it might be as simple as asking them to play in their room. For teens, it might be better to have certain conversations when they are out of the house and invite them to participate directly in others.
Caregivers might not have all the answers — like knowing when a child’s parent is coming back — but they can create a sense of consistency and stability in how they respond to kids’ questions, too.
Avoid undue reassurance (“Everything is going to be fine”) or over-promising (“They’ll be back in two weeks”) by focusing on what kids can expect, says Dr. Gee. For example: “What I can tell you is that I’m here for you, and I’m going to be with you until he’s back,” or “You’re safe with me, and I’m going to stay with you through this really hard time.”
Children are sensitive to tone, Dr. Alexander says. “So, if you’re having really big emotions that are out of context for a child, the child is looking at these emotions and trying to understand what’s happening. ‘Am I in danger in this specific moment?’”
She says it helps to have conversations about these moments, especially with younger kids. “Like, ‘I know you noticed mommy crying. We’re feeling really big feelings, and this is how we’re going to deal with those big feelings. I’m going to take a break. I’m going to get a sip of water. Whenever you’re having big feelings, I want you to let me know so that I can help you try doing the same things,’” Dr. Alexander says, explaining the importance of naming the emotion and then teaching kids that there are ways of dealing with it.
The effects of traumatic separation can persist even after a child and their caregiver are reunited. Traumatic separation, like other adverse childhood experiences, puts kids at risk for a host of long-term medical and mental health conditions, including depression, anxiety, attention issues, and post-traumatic stress disorder (PTSD).
But Downie notes that not everyone who experiences traumatic separation develops PTSD. “Just because someone’s experiencing trauma now doesn’t mean that it’s going to become a PTSD diagnosis,” she says. “A lot of the behaviors that we’re talking about are normal and expected. There’s an adjustment period when a separation happens.” But if symptoms persist or escalate over several months, a child may need more serious support.
While not every child who experiences a separation may receive a trauma diagnosis or require treatment, cognitive behavioral therapy (CBT) — and the more specific trauma-focused cognitive behavioral therapy (TF-CBT) — is the “gold standard,” says Downie. TF-CBT is specifically for children experiencing trauma-related symptoms. An important component of TF-CBT is creating a trauma narrative, where kids create a story about what happened to help them process it. “But if you have a child who is not ready to process and integrate that trauma, you can’t force the pacing of the treatment,” she says.
In short, a good clinician will follow a child’s lead — even if that means just sitting in the same room with them to build trust. “People really need to feel like they’re being heard and that they can trust someone,” Downie says. Which is why a supportive caregiver or trusted adult can make a big difference.
“If people can take anything away from this, it’s that you want to make kids understand that that they’re not responsible for what’s happened and that people do care about them,” Downie says. “Kids are really resilient, and they can adapt in a good-enough environment. They don’t have to have everything to be successful.”
The post What Is Traumatic Separation? appeared first on Child Mind Institute.
MADRID — Spanish authorities on Friday were preparing to receive more than 140 passengers and crew members on board a hantavirus-stricken cruise ship headed for the Canary Islands, where health officials have said they will perform careful evacuations.
The vessel is expected to arrive Sunday at the Spanish island of Tenerife, off the coast of West Africa, and passengers will be taken to a “completely isolated, cordoned-off area,” said the head of Spain’s emergency services, Virginia Barcones.
Roche has signed a deal to pay $750 million upfront for Boston-based PathAI, an acquisition by the Swiss pharmaceutical giant to speed up its use of artificial intelligence to help pathologists diagnose disease.
The agreement, which is expected to close in the second half of the year, could generate an additional $300 million for PathAI if it leads to the achievement of certain milestones.
“Joining forces with Roche marks a new era for PathAI, enabling us to realize our mission of improving patient outcomes through AI-powered pathology at unprecedented scale and speed,” said Andy Beck, chief executive and cofounder of PathAI, in a statement. “Roche’s global infrastructure and expertise will bring our digital diagnostics technology to patients worldwide.”
President Trump has reportedly signed off on a plan to dismiss Food and Drug Administration Commissioner Marty Makary. It would be the latest high-profile departure to hit Robert F. Kennedy Jr.’s health department.
Makary has served in the role for a little over a year. His tenure was ambitious, filled with the announcements of dozens of new initiatives, including efforts to shorten drug review timelines, crack down on misleading ads, and pressure the food industry to remove chemical dyes.
Capricor Therapeutics accused Nippon Shinyaku and its U.S. subsidiary of failing to follow through on marketing plans for a Duchenne muscular dystrophy treatment, and refusing to fix a pricing glitch that was belatedly discovered in their exclusive distribution agreement.
A key issue is a “fatal flaw” in a pricing formula that would make it “economically impracticable” for the therapy to reach patients covered by Medicare, Medicaid, and private insurers, according to a lawsuit filed in a New Jersey state court on Thursday. Nippon Shinyaku and NS Pharma, the subsidiary, disclosed the problem in March 2025.
Basically, the formula ties Medicare reimbursement to the price that Capricor would charge NS Pharma, since it would be the only U.S. buyer. But as it stands, the lawsuit indicated that health care providers would get reimbursed less than they would pay to cover the cost of acquiring and administering the medicine, which is called deramiocel.
MIT Technology Review Explains: Let our writers untangle the complex, messy world of technology to help you understand what’s coming next. You can read more from the series here.
Eight passengers aboard a Dutch-flagged cruise ship have contracted a type of hantavirus, a rare virus transmitted by rats. Three of them have died. As the ship prepares to dock in the Canary Islands, plans are being finalized to let the remaining passengers and crew disembark safely.
The virus in question appears to have a high fatality rate. Read on for answers to the big questions surrounding the outbreak—and to hear why health experts don’t expect a rerun of the covid-19 pandemic.
Hantaviruses are a group of viruses that typically infect rodents but can be transmitted to humans through exposure to the animals or their droppings, urine, or saliva. The viruses don’t seem to cause illness in rodents, but they can make people very unwell. The symptoms can depend on the type of hantavirus a person has been exposed to. Varieties found in the Americas can cause hantavirus cardiopulmonary syndrome, which affects the lungs and heart and has a fatality rate of up to 50%.
That condition made headlines last year when it caused the death of pianist Betsy Arakawa, the wife of actor Gene Hackman.
On April 6, a man aboard the MV Hondius developed respiratory symptoms. He became very unwell and died just five days later. His wife, who left the ship at the island of Saint Helena, also developed symptoms. Her health deteriorated during a flight to Johannesburg, South Africa, and she died the following day, on April 26. South Africa’s National Institute of Communicable Diseases tested samples taken from the woman and confirmed that she had hantavirus.
A third person aboard the ship, who developed symptoms on April 28, died on May 2. Four other passengers who became ill were evacuated—one to South Africa and three to the Netherlands.
An eighth person had disembarked in Saint Helena and reported similar symptoms once he was in Zurich, Switzerland. A team at Geneva University Hospitals confirmed that he had become ill from the Andes virus—a form of hantavirus that can be spread between people.
Health experts don’t believe so. They stress that the situation is nothing like the one the coronavirus that causes covid-19 presented in 2020. For a start, the Andes virus is not a mysterious new virus—scientists already have an understanding of it, and Argentina is sharing diagnostic kits it has already developed.
The virus also doesn’t spread in the same way. Officials at the World Health Organization emphasized that the spread of hantavirus requires close contact—the kind a person might have with a partner, household member, or medical caregiver.
The cruise ship outbreak represents “a specific confined setting where people are interacting in a prolonged close contact,” Abdirahman Mahamud, the alert and response director for the WHO’s health emergency program, said at a press event on Thursday. “With the experience our member states have, and the actions they have taken, we believe that this will not lead to a subsequent chain of transmission.”
All the remaining passengers have been asked to stay in their cabins, which the WHO says are being disinfected. Doctors and health professionals from the WHO and the European Center for Disease Prevention and Control have boarded the ship and are assessing everyone on board.
So far, no one else on board has developed symptoms, Maria Van Kerkhove, WHO acting director for epidemic and pandemic management, said at the press event. That’s “a good sign,” she said, but she added that the Andes virus has a long incubation period (around six weeks). Passengers are being advised to wear a medical mask when they leave their rooms.
At the same event, WHO director general Tedros Adhanom Ghebreyesus said he was in regular contact with the ship’s captain, who was reporting that “morale had increased significantly” since the ship started its journey to the Canary Islands.
The Andes virus is the only hantavirus that is known to be transmitted between people. That transmission seems to rely on prolonged, intimate contact.
There was an Andes virus outbreak in Argentina around eight years ago. Between November 2018 and February 2019, there were 34 confirmed cases of infection, and 11 deaths. That outbreak was triggered when a person with symptoms attended a social gathering, said Tedros. “We are in a similar situation right now,” he said. “A cluster in a confined space with close contact.”
The fact that the 2018 outbreak was limited to 34 cases should be somewhat reassuring, he implied. “We believe this will be a limited outbreak if the public health measures are implemented and solidarity is shown across all countries,” he said.
Unfortunately, we don’t have any specific antiviral treatments or vaccines for hantavirus. The WHO recommends early intensive care for people who develop symptoms. “This can save lives,” Anaïs Legand, WHO technical lead on viral hemorrhagic fevers, said on Thursday.
We don’t yet have an answer to that. But we do know that the couple who died had traveled through Argentina, Chile, and Uruguay on a birdwatching trip before they boarded the ship. That trip included visits to areas where species of rats that carry the Andes virus are known to live. The WHO is working with authorities in Argentina to try to retrace the couple’s movements on that trip.
We don’t yet know for sure. The WHO is receiving reports of “potential suspect cases,” Van Kerkhove said at the Thursday briefing. Some of them have links to the ship or its passengers. Each “alert” will be followed up by health authorities in the relevant country, she said.
Five US states have said they are monitoring US nationals who have disembarked from the ship. WHO officials are stressing that they are still sharing technical information with the US Centers for Disease Control and Prevention. “Things are … as they used to be,” Tedros said. “WHO’s mission is to help the world to be safe … and we want the American people to be safe as well.”
But it’s worth noting that cuts made by the Trump administration aren’t exactly putting the US in a good position for events like these. Last year, all full-time employees in the CDC’s Vessel Sanitation Program—which helps prevent and control illness outbreaks on cruise ships—were laid off. Further cuts to the CDC have left public health experts worried about how ill prepared the US is to deal with future disease outbreaks.
Any suspected cases will be monitored by health authorities. Passengers are due to disembark in Tenerife in the Canary Islands on Sunday, May 10, and the WHO has said it will work with the Spanish government to ensure that the risk to residents remains low and that the passengers are treated with dignity and respect.
In the meantime, scientists are working to fully sequence the genome of the virus from patient samples. They want to find out if it is different from the viruses involved in the previous cases. “So far, we haven’t seen anything unusual,” said Van Kerkhove.
I learned about hantavirus misinformation this week in the same way I now learn about most public health misinformation: My followers sent it to me.
Within hours of the first headlines about a hantavirus outbreak linked to the expedition cruise ship MV Hondius, my DMs started filling with screenshots. One was from the account of a Texas doctor who became well known during Covid for promoting ivermectin. She was already telling followers that ivermectin would work against hantavirus, too.