I tidied the house properly a few weeks ago. The good sort of tidy, where you stand in the doorway afterwards feeling quietly heroic and take a photograph of the worktop.

By the following week I could not find the good scissors, the charger for the thing that actually needed charging, or a letter I had been sent that I definitely had not thrown away.

None of it was lost. All of it was put away. It has taken me most of my adult life to understand that those are two different things.

I own three pairs of the same trousers

Not because I loved them so much I went back for more. Because I bought a pair, hung them in the wardrobe, and within a few weeks had no memory of owning them at all. So I bought them again. And then, later, once more.

The wardrobe is where clothes go to stop existing. I know this about myself now, so I have a rule. Anything new stays out, on the chair, over the back of a door, somewhere I will physically walk past it, until I have actually worn it once. Once it has been on my body there is a memory attached to it, and it survives the wardrobe. Before that, it is gone.

To anybody else it looks like a woman who cannot be bothered to hang her shopping up. It is in fact the only reason I ever wear anything I buy.

Christmas, several times a year

The same thing happens with anything that goes into a bag. I bring presents home from my mum's at Christmas, put the bag under the bed because that is a sensible place for a bag, and it ceases to exist. Not "I forgot about it for a bit". It leaves my head completely, as though it never happened.

And then in April, hunting for something else entirely, I find them. All of them. And it is genuinely lovely. I get Christmas two or three times a year, sprung on me by my own past self, and I am delighted every single time.

That is the funny version. The version that actually costs me is the online shop. I will order eight or ten small things at once, an eyeliner, a face cream, the ordinary bits you top up. They arrive, I feel briefly organised, and I put them away in a drawer where they belong.

By the next day I do not remember buying them. Not vaguely, not "oh yes, of course". They are simply not in my head. So a few weeks later I buy the face cream again, because as far as I am concerned I have run out.

Three pairs of trousers and two face creams is not a personality quirk. It is money, repeatedly, for things I already own.

A museum of everything I have ever owned

So here is the trap I have lived in for forty-odd years.

I would love a tidy house. I mean that. I like calm rooms, I like clear surfaces, I look at other people's kitchens with something close to grief. But tidy means out of sight, and out of sight means gone, and gone means I stop taking the tablets, miss the appointment, buy the trousers again.

So instead I live in what is essentially a museum of everything I have ever owned. Every surface an exhibit. Trying desperately to be organised, and surrounded at all times by the evidence that I am not.

The shame of that is the part people do not see. You are not just untidy. You are untidy while trying extremely hard, which is a much lonelier thing to be.

So what is actually going on

The internet calls this "ADHD object permanence", and I use the phrase myself because everybody knows what it means. It is, strictly speaking, the wrong name.

Object permanence is a Piaget thing. Babies, a toy, a blanket over the toy. At around eight months old a baby works out that the toy still exists under there, and we all pass that test and never think about it again. I am perfectly aware the trousers are still in the wardrobe. I could draw you a diagram of the wardrobe.

What is actually happening is two other things, and they are both well described.

Working memory is your brain's desk. It is the small surface where you hold things you are currently using. In ADHD that desk is smaller and the things on it slide off more easily. Once something is not in front of you, there is nothing holding it in active awareness.

Prospective memory is remembering to do a thing later. Research consistently finds that people with ADHD do much better when an intention is attached to something they will see, and much worse when it depends on remembering at the right moment out of thin air.

Russell Barkley, who has spent his career on this, describes ADHD less as a deficit of attention and more as a problem of self-regulation, and points out that one of the jobs of working memory is to hold a goal in mind in the absence of a cue. When that runs weak, the cue has to come from somewhere else. It has to come from the room.

Which is what the pile on the side actually is. It is not mess. It is a to-do list that happens to be made out of objects. The tablets by the kettle mean take your tablets. The letter on the chair means deal with the letter. Cognitive scientists have a proper term for this, external cognition, which sounds a great deal more dignified than "stuff everywhere", and means the same thing.

I am not being disorganised. I am running my memory outside my head, because outside my head is where it works.

This is not hoarding, and the difference matters

People conflate the two constantly, and it leads to genuinely bad help.

In hoarding disorder, the driver is saving. There is a strong attachment to the objects and real distress at the thought of losing them. The stuff is kept because parting with it is unbearable.

What I have is the opposite in almost every respect. I have no attachment whatsoever to the envelope on the side. I would be delighted for it to be gone. It is out because out is the only place I can see it. Ask me to throw the trousers away and I will hand them to you. Ask me to put them in a drawer and you have effectively taken them off me.

The two can occur in the same person, and when they do it needs proper support. But treating an ADHD memory system as though it were hoarding, and "helping" by clearing it, does exactly the harm you would expect.

What actually helps

Nothing fixes it. Everything is a trade-off between how tidy the room looks and how well the person in it functions. But some things genuinely help.

  • Doors are the enemy. Anything behind a solid door has left the building. Open shelving beats cupboards, every time.
  • Clear containers, never opaque ones. A clear box is not tidier than a cardboard one. It is just still visible, which is the entire point.
  • Label the outside of the drawer, or take a photograph of what is in it and stick it on the front. It feels ridiculous. It works.
  • Pick one surface and let it be the surface. If everything visible has to live in one designated place, the rest of the house gets to be calm and you still have your memory.
  • Wear it once before it goes away. Use it once, open it once, put it on once. After that it survives storage.
  • Tell the people you live with why. Honestly, this was the single most useful thing I ever did. Not "sorry about the mess" but "that pile is doing a job, please leave it".

And stop apologising for it quite so much. I am still working on that one.

Why I am telling you all this

Because of what happens to this when a person gets old.

Picture somebody who has done what I do, for seventy years, without ever knowing why she needed to. Nobody assessed her generation for ADHD, least of all the women. She was called scatty and disorganised and she built her whole life around leaving things where she could see them, and it worked, and she never once had a word for it.

Then she moves into a care home.

Her room is now tidied every day by a housekeeper who is kind, competent, and has been correctly trained that a clear floor is a safer floor. And she is right about that. Falls are real.

So the tablets go from the windowsill into the bedside drawer, which is exactly where tablets should go. The letter goes into the folder. The glasses go into the case. Everything is put away properly, and the room looks lovely, and every single item has now moved to a place where, for this particular woman, it does not exist.

What happens next gets written down as decline.

She is more confused this week. She is not taking her tablets. She keeps asking for things she already has. She rummages. She is unsettled in the afternoons. She moves things around and gets upset when they are moved back.

Nobody has done anything wrong. Not one person in that building has done anything wrong. A fifty-year coping system was dismantled in an afternoon, by somebody doing her job well, and the resulting disorientation has been recorded as the dementia progressing.

Here is the cruellest bit of the timing. This happens at precisely the moment she can least explain it. At forty she would have said "please leave my things out, I need to see them, I know it looks a mess". At eighty-four with dementia she cannot make that argument. She can only become somebody who is difficult about her room.

What I would ask you to do

If you work in a care home, before you tidy a resident's room, ask one question: is this mess, or is this a system?

The test is not complicated. Watch what happens when it is gone. If she glances round once and gets on with her day, it was mess. If the routine falls apart, if she is looking for things all afternoon, if the tablets stop being taken, then it was load bearing and you have removed a wall.

Then write it down, and not as "likes her things left out", which will not survive a shift change. Write it as what it is:

Mrs Ellis uses visible objects as a memory aid. Do not tidy items from the windowsill or the top of the chest of drawers. This is a functional memory system, not clutter. Items may be dusted around and must be replaced exactly where they were.

That version survives the agency staff, the new housekeeper and the night shift. The other version does not.

And if you are the family, tell them this before the move, not after. It is one of the most useful things you can possibly put on paper about somebody, and nobody will think to ask you for it.

If you want the fully referenced version of all this, with the safeguarding and Regulation 9 implications set out properly, I have written it up as a research paper on object permanence in ADHD and the care home environment. If you would rather write down how somebody's own system works while they can still tell you, that is what the Personhood Profile is for.

Now, if you will excuse me, it is coming up to autumn and I have a strong feeling there is Christmas under my bed.