How were you feeling last Tuesday?
You can't answer correctly. It's not your fault — it's a well-documented flaw in human pain memory, and it has a name.
Try it yourself. How were you feeling last Tuesday? Not today, not yesterday — last Tuesday, a week ago. Most people can answer the question without hesitating. The problem is that the answer is rarely correct.
That's not a claim that you're forgetful. It's a claim about how memory for pain works in everyone, and research has a name for it: recall bias.
The study that asked twice
A study of chronic pain patients put the method to the test. Participants had to recall and rate their pain for a whole week at a time, four weeks running. At the same time they recorded their pain in the moment — several times a day, in an electronic diary, during the study's last two weeks. That made it possible to compare the remembered week against what people actually reported while it was happening.
The study went a step further and compared something more: patients' own assessment of whether their pain had changed over the two weeks, against the change that could be calculated from the momentary recordings. Two different methods of answering the same question — one looking back, the other in the moment.
Memory edits the past
This is a recurring observation in headache research: one of the main limitations of relying on self-reported triggers lies in the reliability of the patient's own memory and selection. Not because patients lie. Because memory for something as fleeting as pain level isn't a recording. It's a reconstruction, and the reconstruction leans on how you feel now, what you expected, and what was most striking to remember.
A bad headache day leaves a stronger trace than ten ordinary days without one. If a week later you have to sum it up into a single answer, it's the bad day that wins — whether or not it was representative.
Ecological Momentary Assessment: repeated questioning about current behaviour and experience in real time, in the person's own environment. The purpose is to minimise recall bias and make it possible to study the processes that actually govern how we feel.
Shiffman, Stone & Hufford, Annual Review of Clinical Psychology, 2008The solution was to stop asking backwards
Research didn't find a way to fix memory. It found a way around it. The method is called Ecological Momentary Assessment, EMA for short, and the idea is simple: instead of asking people how they felt, you ask them how they feel, while they feel it. In the moment, repeated, in the person's own environment — not reconstructed afterwards in a clinic.
That sounds like a technicality. It's the difference that decides whether data describe what actually happened, or what's best remembered.
Why the app asks right away
That's exactly the idea Aneroid is built around. The app doesn't ask you to keep a diary and sum up in a week's time how things have been. It asks when the pressure changes — and three times daily for no reason — and it asks how you're feeling now. Not last Tuesday.
Aneroid is not a medical device and makes no diagnoses. The app collects your momentary answers over time, so you can see for yourself what your data actually show — not what you remember.
Sources
- Shiffman S., Stone AA, Hufford MR (2008). „Ecological Momentary Assessment." Annual Review of Clinical Psychology. Read
- Broderick JE, Stone AA et al. „Understanding recall of weekly pain from a momentary assessment perspective: absolute agreement, between- and within-person consistency, and judged change in weekly pain." Pain. Read
- „Perceived Migraine Triggers." Practical Neurology. Read