Psychology says people who use sticky notes instead of phone reminders may be using their surroundings to train their memory

Most people now put reminders on their phones and let an app handle the rest. A meeting alert pops up, a calendar sends a notification and a task sits somewhere in a long digital to-do list. But some people still write things down on paper and stick those notes where they can see them. That simple habit may have something to do with how memory works.

Research from the University of Tokyo found that people who wrote information on physical paper showed stronger brain activity when they later tried to remember it compared with people who used tablets or smartphones. The findings, published in Frontiers in Behavioral Neuroscience, suggest that the physical and spatial details of paper can provide additional clues for memory.

Paper gives the brain more to remember

The 2021 study involved 48 people aged between 18 and 29. They were asked to read a fictional conversation containing different appointments, class times and assignment deadlines, and then record those details using either a paper datebook, a tablet or a smartphone.


The paper group finished the task in about 11 minutes. Tablet users took around 14 minutes, while smartphone users needed about 16 minutes.

An hour later, participants were asked questions about the information while researchers monitored their brain activity using functional MRI scans.

Those who had used paper showed greater activity in brain areas linked with language, visualisation and memory, including the hippocampus. They also performed better on the simpler memory questions.

Professor Kuniyoshi L. Sakai, a neuroscientist at the University of Tokyo and one of the study's authors, said, "Actually, paper is more advanced and useful compared to electronic documents because paper contains more one-of-a-kind information for stronger memory recall."

The researchers believe physical paper offers details that a digital screen does not. A handwritten note has a particular position, size and appearance. It can be circled, moved, folded or placed next to something else. A phone reminder, on the other hand, usually appears in the same digital interface as many other alerts.

A sticky note becomes part of the surroundings

This is where the humble sticky note gets interesting.

A note saying "Call John" on a desk is not only a piece of written information. It is also sitting in a particular place. You might see it when you sit down to work, notice it next to your keyboard or associate it with the object beside which you placed it.

That is close to the idea of environmental cueing, where features of your surroundings can prompt you to remember something or carry out an action.

A phone reminder can tell you when something needs to happen. A sticky note can become part of the physical setting in which you need to remember it.

The University of Tokyo researchers also suggested that digital documents can be made more personalised through highlighting, circling, underlining, arrows, handwritten notes and virtual sticky notes. These additions may provide some of the spatial information that makes physical paper useful for memory.

Why location may matter

The study found stronger activation of the hippocampus among participants who used paper. The hippocampus plays an important role in memory and navigation, which led the researchers to suggest that richer spatial information from physical paper may have helped participants form stronger retrieval cues.

Sakai explained the difference using a familiar example: "Digital tools have uniform scrolling up and down and standardized arrangement of text and picture size, like on a webpage. But if you remember a physical textbook printed on paper, you can close your eyes and visualize the photo one-third of the way down on the left-side page, as well as the notes you added in the bottom margin."

This does not mean every sticky note will automatically improve memory, or that phone reminders are useless. Digital reminders are still extremely helpful, particularly for deadlines and events that need precise alerts.

But when a reminder is something you want to keep in your head, putting it somewhere visible may give your brain another clue to work with.

The study's main message was simple. Sakai said, "Our take-home message is to use paper notebooks for information we need to learn or memorize."