The Interstitial Journal blog · Built on evidence, not hype
Interstitial vs. End-of-Day Journaling: Which Fits the Workday?
There are two natural moments to write about your work. One is during the day, at the seam between tasks — a quick timestamped line as you switch. The other is after it, a short reflection once the day is done. They sound like versions of the same habit, but they lean on different research and do different jobs. Here's an evidence-based comparison of what each is actually good for — and why, in the end, they stack rather than compete. We'll be clear about where the support is solid and where it runs thin.
Interstitial journaling: a tool for continuity
Interstitial journaling happens in the gaps — you jot a line when you start, switch, get stuck, or finish something. Its evidence base is about navigating the day while you're in it. The relevant findings are about the cost of switching: after you move to a new task, part of your attention stays stuck on the previous one — attention residue — and the new task suffers until it clears.1 Strong
The most direct support for doing something about it in the moment comes from Sophie Leroy and Theresa Glomb: before turning away from a task, taking a moment to note where you are and what your next step is — a brief "ready-to-resume" plan — reduced residue and protected performance on what came next.2 Moderate A timestamped line written at the switch is that plan. There's a related reason it helps: noting an unfinished task and its next step is a form of plan-making, and plan-making has been shown to quiet the intrusive pull of unfinished goals — the lingering "I still need to…" that taxes attention.3 Moderate
The interstitial line (written at the seam): Where am I leaving this, and what's the first step back?
"Paused the deck on slide 6; next: draft the pricing slide, then send to Sam."
End-of-day journaling: a tool for learning
End-of-day journaling does something different. You're no longer navigating; you're stepping back to make sense of what happened. Its strongest support comes from research on reflection. In a series of studies, Giada Di Stefano and colleagues found that people who spent a few minutes at the end of a task deliberately reflecting on what they'd learned went on to perform meaningfully better than those who simply kept doing — articulating the lesson, it seems, helps it stick.4 Moderate That's the engine of an end-of-day note: it converts a day of doing into something you actually retain.
There's a second, older strand worth naming carefully. James Pennebaker's expressive writing work found that writing about emotionally significant experiences can, over time, be associated with improvements in wellbeing.5 Moderate It's a real and influential body of work — but it's about processing meaningful experience, not a productivity technique, and effects vary a great deal between people. We mention it because end-of-day writing can quietly do this job too, not because it guarantees it.
Side by side
| Interstitial (between tasks) | End-of-day (once, after) | |
|---|---|---|
| Main job | Continuity — clean switches, a clean return | Learning — consolidating what the day taught you |
| Leans on | Attention residue, ready-to-resume plans, plan-making1,2,3 | Reflection and learning; expressive writing4,5 |
| When | Many times a day, at the seams | Once, at day's end |
| Costs you | A few seconds, in the moment | A few minutes, with hindsight |
| Best for | Fragmented, interrupt-heavy days | Drawing lessons; a sense of closure |
So which should you do?
The framing is a false choice. They aren't rivals; they're two instruments for two problems. If your days are chopped up by meetings and messages, the interstitial line earns its keep many times over — it's the one that fights residue while you still feel it. If you want to learn from the work rather than just survive it, the end-of-day reflection is the stronger tool. Most people benefit from both, and they compose neatly: the timestamped lines you left through the day become the raw material for a richer, more concrete reflection at the end of it — far better than trying to recall a blurred day from memory.
A practical pairing: capture interstitial lines as you go, then read them back for two minutes before you close the laptop. The day's notes are your end-of-day prompt — specific, timestamped, and already written.
Where the evidence ends
Let's keep the claims calibrated. Attention residue and the ready-to-resume effect are well-supported; the benefit of reflection for learning is moderately so; expressive writing for wellbeing is real but variable and outside the productivity frame. What has not been formally trialed is the specific composite — "do both, every day, and your work improves over months." That's a reasonable bet built from well-studied parts, but it's a bet, and we'd rather say so than invent a number. You won't find a fabricated productivity percentage here — that restraint is the whole point of this app. Read more on our science page, and how your notes stay private on our privacy page.
Interstitial Journal is on the App Store
A minimalist, private place to capture the moments between tasks — type or speak a timestamped note at the seam, tag it, optionally name a mood. Read the day back in two minutes at the end. No account, no tracking; your notes sync privately through iCloud. Available now for iPhone, iPad, and Mac.
Download on the App Store →References
- Leroy, S. (2009). Why is it so hard to do my work? The challenge of attention residue when switching between work tasks. Organizational Behavior and Human Decision Processes, 109(2), 168–181. doi:10.1016/j.obhdp.2009.04.002
- Leroy, S., & Glomb, T. M. (2018). Tasks interrupted: How anticipating time pressure on resumption of an interrupted task causes attention residue and low performance on interrupting tasks — and how a "ready-to-resume" plan mitigates the effects. Organization Science, 29(3), 380–397. doi:10.1287/orsc.2017.1184
- Masicampo, E. J., & Baumeister, R. F. (2011). Consider it done! Plan making can eliminate the cognitive effects of unfulfilled goals. Journal of Personality and Social Psychology, 101(4), 667–683. doi:10.1037/a0024192
- Di Stefano, G., Gino, F., Pisano, G. P., & Staats, B. R. (2016). Making experience count: The role of reflection in individual learning. Harvard Business School NOM Unit Working Paper No. 14-093. doi:10.2139/ssrn.2414478
- Pennebaker, J. W. (1997). Writing about emotional experiences as a therapeutic process. Psychological Science, 8(3), 162–166. doi:10.1111/j.1467-9280.1997.tb00403.x
Interstitial Journal is a private note-taking tool for reflection, not a medical or mental-health treatment. The research described here supports specific, narrow claims; combining interstitial and end-of-day journaling as a daily practice has not been formally trialed. If you're struggling with your wellbeing, please speak with a qualified professional.