Mental load and forgetfulness: why you forget everything

"What did I come into the kitchen for, again?"

You walk into a room. You stand there for three seconds. You walk out. You forget the pediatrician appointment you wrote down this morning. You run into another mom at school and spend five long seconds fishing for her name. You put your keys in the fridge.

If you're reading this, you've probably been living in this fog for months — maybe years. You wonder if you're losing it, if it's age, if it's something serious. The good news: almost certainly not. The less good news: until the cause is named, it'll keep happening.

The culprit has a name. It's mental load. And it's not a metaphor — it's a measurable brain mechanism, one that fills your working memory like a computer whose RAM is permanently maxed out.

What science says about your memory

Your brain has two types of memory that matter here: working memory (active, very short-term) and long-term memory (durable storage).

Working memory is what lets you hold a phone number in your head while you dial it, follow a conversation while you cook, or keep a mental grocery list while shopping. Its capacity is limited. Research by psychologist George Miller, refined by Nelson Cowan in the 2000s, puts this capacity at 4 to 7 simultaneous items in a healthy adult.

That number is low. It's even lower in someone who is tired, stressed, or in chronic cognitive overload: the limit drops to around 3 to 4 items. Beyond that, your brain starts dropping information mid-use. Which is exactly what you're experiencing.

An active mother holds, according to estimates from sociological research on domestic labor, between 30 and 50 "open mental processes" on an ordinary day: call the sitter, book the orthodontist, buy toothpaste, sign the school note, order the birthday gift for Saturday, restock diapers, check there's bread for tomorrow, reply to the teacher, track the power bill, plan summer camp, remember mother-in-law is coming Tuesday.

Your working memory can hold 4 to 7 of those at once. You have 30 to 50. The rest must be stored somewhere — in long-term memory, on paper, in an app, or… it gets lost. It's basic math.

The biological cocktail of chronic forgetting

On top of cognitive overload, there's a biological factor. When stress becomes chronic, your brain releases excess cortisol. This hormone — essential in short-term danger — becomes toxic to two brain structures central to memory: the hippocampus (which consolidates memories) and the prefrontal cortex (which drives working memory and attention).

Research on chronic stress and cognition shows that sustained high cortisol levels cause measurable shrinkage of the hippocampus and impair the brain's ability to form new memories. This is what the scientific literature calls "brain fog".

Add to this sleep deprivation — which, according to the French National Sleep Institute (INSV), affects 49 % of mothers of young children, versus 32 % of fathers. And it's during deep sleep that your brain "replays" and consolidates the day's memories. Less sleep means less recording. Our article [Mental load and sleep: why your brain won't switch off](/en/blog/mental-load-sleep) unpacks this mechanism in depth.

Cognitive overload + cortisol + sleep debt = chronic forgetting. You're not losing your mind. Your brain is doing exactly what it's supposed to do under these conditions.

The "I'll remember" trap

A mental experiment. It's 10 p.m. You're brushing your teeth. You suddenly remember you need to email the teacher about the rescheduled parent-teacher meeting. You think: "I'll do it tomorrow morning, I'll remember."

You won't remember.

Not because you're careless. Because your brain is in "everything open" mode. You've added one more tab to your mental file. And the more tabs you add, the higher the chance this one closes on its own.

Research consistently shows that more than 8 out of 10 parents — overwhelmingly mothers — report being affected by mental load. That's become the norm. But norm doesn't mean fate. Pulling information out of your head and storing it elsewhere (paper, app, sticky note, shared calendar) isn't a sign of memory failure — it's the cognitive strategy recommended by applied neuroscience.

It's exactly what airline pilots, surgeons, and head chefs do as standard practice: they don't try to remember everything. They use checklists. If NASA and the FDA have endorsed this method for hyper-trained humans in life-critical contexts, you're allowed to use it too, for the kids' afternoon snacks.

7 science-backed methods to get your memory back

Here are seven strategies, ranked by effectiveness, to clear the fog.

1. Externalize everything that can be externalized

This is method #1, and by far the most effective. Every appointment, every grocery list, every idea that pops up should leave your head within 30 seconds. Calendar, dedicated app, notebook — the medium doesn't matter. What matters is that no important information lives only in your head.

This is precisely what a tool like [Mental Loadless](/en) is for: becoming the household's shared external memory, so you no longer have to carry mentally what no one else sees. Users of externalization systems (Getting Things Done and similar frameworks) consistently report around 30 % less "sense of forgetting" after 8 weeks.

2. Do a daily brain dump

Once a day — ideally in the evening — sit down for 10 minutes with paper (or your app) and empty your head. Everything. Every household-related thing you thought about today. No ranking. No judgment. Triage comes later.

This practice, championed by organization coaches and validated by cognitive psychology, frees up working memory immediately and improves sleep quality. Many mothers who adopt this ritual report falling asleep faster within the first week.

3. Cut load at the source

Externalizing is treating the symptom. To treat the cause, you need to transfer entire domains to your partner — not "help" on tasks, but take full ownership of a slice of family life (health, school, groceries, birthdays, admin).

Our guide [How to split household tasks fairly](/en/blog/repartir-taches) lays out a concrete protocol for this redistribution by domain. As long as you stay the household's "project manager", your working memory stays saturated — no matter what organization tool you use.

4. Protect your deep sleep

Deep sleep is when your hippocampus consolidates memories. It's non-negotiable. According to the INSV, sleeping under 6 hours for several weeks reduces memory consolidation by 40 %.

Three priorities: go to bed at the same time (±30 minutes), no screens 30 minutes before bed, and do a brain dump before lying down (method 2). If insomnia persists more than 3 weeks, talk to your doctor.

5. Reduce forced multitasking

Cooking while helping with homework while answering an email while thinking about tomorrow's groceries: your brain thinks it's doing four things, but it's actually switching between four tasks, and each switch burns working memory. Research on task switching cost estimates this loss at 20–40 % efficiency per task.

Protect 2 to 3 mono-task windows per day. Even 15 minutes of cooking without phone, without questions, without a mental list, makes a measurable difference on your end-of-day memory.

6. Use the 2-minute rule

If a task takes less than 2 minutes (send a short email, sign a note, reply to a message), do it immediately. Don't store it in your "for later" memory. The mental cost of keeping it in mind exceeds the cost of doing it.

This rule, popularized by David Allen, frees dozens of micro mental-tabs per day. It's one of the highest-ROI interventions in memory management.

7. Accept strategic forgetting

Not all information deserves to be remembered. The classmate's gift you see twice a year. The exact date of the cat's last vaccine reminder. The 3rd-floor neighbor's name. Separate what absolutely must be tracked from what can be delegated to the internet, to your vet, or… forgotten without consequence.

This "cognitive hygiene" — actively deciding not to carry certain information — is one of the most liberating practices flagged by specialist organization coaches.

When to see a doctor

If your forgetting touches long-term memory (you forget important events from your past), if you get lost in familiar places, if loved ones notice a sudden behavioral shift, or if forgetting comes with persistent dark thoughts, see a doctor without delay. These signs may indicate a medical cause (depression, thyroid issue, deficiency, more rarely a cognitive disorder) that warrants a full checkup.

For the other cases — the vast majority — the first step isn't medication. It's a structural change in your relationship with memory. Our article on [signs of mental load](/en/blog/signs-of-mental-load) helps you run a full diagnostic.

Your brain isn't a hard drive

Modern culture has sold us the story that a "good mother" keeps everything in her head. That's wrong. It's actually the opposite: the best-organized brains remember almost nothing. They sort, they offload, they delegate, and they keep their working memory free for what really matters — being present, thinking, creating, feeling.

If your head is full of lists, reminders, appointments and anticipations, that's not a strength — it's a leaky system. Making it visible on the outside — on paper, in a shared app, in a conversation with your partner — is how you get your brain back. And with it, your memory.

[Mental Loadless](/en) is built exactly for this: turning those 30 to 50 mental tabs into a shared external memory, where you're no longer alone carrying what no one else sees. Because forgetting should never be a personal problem when the real issue is collective.