"My mind is always full of things," said Stacie Matthias, a mother of three.
"I have a long to-do list in my head before I go to bed."
She was talking about the concept of “mental load”—the burden of planning, organizing, remembering, and anticipating the tasks that keep a household running.
These tasks include remembering your child's school travel schedule, checking parent WhatsApp groups for updates, noting areas of the home that need cleaning, monitoring your child's sleep schedule, scheduling doctor's appointments and buying school uniforms.
Scholars believe that in heterosexual couples, this job falls disproportionately on women — especially mothers — who also do the bulk of the physical housework.
Of course, all relationships and families are different, but research shows there are some clear patterns.
For example, British children have just returned to school after summer vacation. Stacey, a 37-year-old resident from Stockport, told the BBC that she often feels that her mind is particularly busy in September.
"It's that feeling that there's always something to remember, something to organize or something to worry about that makes this time of year extra busy," she said.
For Stacey, this list of responsibilities made her brain feel like a sink that was constantly being filled.
"If you don't have help moving those pots and pans, by the end of the day, the water is overflowing. And then you hit the breaking point."
Scholars from the University of Bath in the UK and the University of Melbourne in Australia conducted a survey on mental load among 3,000 American parents.
It was found that mothers were responsible for 71% of household chores that required mental effort: such as remembering when sheets and towels need to be washed, and remembering when food in the refrigerator needs to be eaten.
The study also found that fathers tackled many tasks that the researchers describe as "episodic" -- things that happen infrequently, such as remembering when to service a car.
Professor Leah Ruppaner from the University of Melbourne describes mental burden as invisible, persistent and boundless.
She told the BBC: "You don't bring the dishes to the workplace, but you bring the mental burden everywhere."
In fact, mental burden is a hot topic on online forums such as Reddit and Mumsnet.
Women turn to these forums for advice on how to talk to their partners about feeling exhausted from trying to juggle so many different responsibilities.
Mothers told the BBC they were often added to the school's WhatsApp group - where parents discuss things such as casual wear days, school trips, birthdays and lost and found items - as the "default representative at home".
Their partners never joined.
For example, Sophia is a 35-year-old mother of three children living in Portsmouth. She uses her child’s school app on her phone to pay for school trips and order lunch. But she said her husband never downloaded the app.
Sofia said she had tried several times to explain the concept of mental burden to her husband, but she felt he didn't understand and dismissed her concerns as "minor things."
"If I just do the tasks directly, these tasks can be completed very quickly. But I have to plan for the tasks, I have to think about the tasks in advance, and I have to stay ten steps ahead at all times," she told the BBC.
Sam Berry, a vice-chancellor and content creator in London who is married with two children, told the BBC that when his wife first brought up the concept of mental burden after the birth of their eldest son, he "didn't quite understand" and was "a bit resistant". Because he thinks he’s already done a lot of things—changing diapers, feeding the kids, etc.
He would ask what he could do to help. But he told the BBC that doing so still puts the responsibility of thinking on the other side.
As Stacey explains, "I always say to my partner: If I still have to ask you to do something, it's just going to add to my mental burden."
After months of talking and listening, Sam understood that it wasn't just completing the task, but the thinking around the task—not just making dinner, but what ingredients were at home, planning the meal, and grocery shopping.
Clinical psychologist Natasha Wallace explained to the BBC that some women come to her for advice because they feel stressed about getting their house in order.
"For them, it's often not one huge source of stress," she says. "It's when they realize they have hundreds of tiny demands to deal with that their brains and bodies simply can't relax, that's when the stress really hits."
She added that many women are on "autopilot." As a result, they are often unaware of how much cognitive load they are under, and this sustained low-level stress can have an impact on the nervous system.
This, in turn, can lead to poor sleep quality, irritability, and decision-making fatigue.
Anita Cleare, parenting expert and author of The Work/Parent Switch, points out that overall cognitive depletion can spill over into our work lives, leading to unsustainable burnout.
Another study found that men with higher incomes performed less physical and mental work in household matters. But when women's income increases, they do less physical housework, but the amount of mental work remains the same.
Claire analyzed to the BBC that women rarely feel that withdrawing from family life is an option, so the choices they face become slowing down their careers, turning to part-time work, or stopping their careers and staying at home - a choice that more and more women are making.
“If you reduce the burden of household chores and reduce the mental burden, you can free up your energy, ability and interest to perform better and better at work.”
Why does this difference occur?
Many women the BBC spoke to said they believed the gap started during maternity leave.
Because women's maternity leave is typically much longer than fathers' paternity leave, they become "default parents" early on, Wallace said.
"If you become the know-it-all, know-it-all-where, all-powerful person, then everyone starts turning to you for any help. So even if you go back to work, you're still that central figure."
In the UK, mothers are entitled to up to 52 weeks of statutory maternity leave, 39 weeks of which are paid. Fathers are entitled to statutory paternity leave of up to two weeks.
Both parents can also choose to share parental leave.
Some employers provide employees with additional parental leave. But most people will earn less while on maternity or paternity leave, which affects the length of leave many fathers take.
Claire believes workplaces can help by setting an example for dads to take paternity leave (rather than just offering it), setting expectations for employees’ contact times and supporting women in career development conversations.
It may also depend on how people view traditional roles.
Zach Watson is a married father of three and a coach in the United States who is committed to sharing the mental burden. He said his grandfather probably never cooked a meal during their married life, and his father only cooked a little.
Many of the women the BBC spoke to wanted their partners to take on certain tasks.
However, he also said that equality doesn't necessarily mean everything is split 50/50 - as one party might work more and the other might enjoy cooking.
Therefore, the focus is on finding what is best for both parties.
Afua Williams, 40, a mother of two in London, said: "If you have traditionally carried more of the mental burden, you may need to accept that your partner may do things very differently to you and that things may not always go smoothly."
How to lighten the load
People interviewed by BBC News shared their tips on how to balance their mental workload:
Communicate clearly with your partner about how you are feeling and the impact of your mental load. Chuck calls it “labelling”—bringing invisible cognitive and emotional labor to light. Don't have these conversations when you're angry or overwhelmed, or the other person will feel like you're "blaming or criticizing," Wallace said.
“See what burdens you can lift,” says Ana Catalano Weeks. She is a co-author of a study examining how mental workload affects work. Do you really need physical birthday cards for your child’s friends? Could you mute WhatsApp in the parent group and only focus on official school emails?
Communicate with your partner regularly—this could be daily, weekly, or quarterly.
Create a shared calendar so everyone knows about birthdays, school meetings, and more.
Wallace said you should take the initiative to take on a task and complete it from start to finish without needing to be reminded.
Don't fall into the "efficiency trap" and think the solution is just to improve your organizational capabilities, Claire said. Remembering that as a parent, it’s the moments of connection with your children that matter most—not the kids not eating certain vegetables—will help redefine expectations for your children.
