"I cannot focus" is one of the most common things people say to a clinician and one of the least useful, because it describes at least five different capacities that fail independently and respond to different things.
Working out which one is yours — or which ones, on which days — changes what gets tried. It is also the single most useful thing you can bring to an appointment.
The five
Starting. Getting from intention to action. Fails as: the four hours before beginning, the task list untouched, the thing you have meant to do since March.
Sustaining. Staying on something once begun. Fails as: reading four pages and retaining none, drifting off mid-paragraph, the meeting you were in for forty minutes and can remember eight of.
Filtering. Keeping out what is irrelevant. Fails as: unable to work with a conversation nearby, every notification capturing you completely, the hum of the fridge being a problem.
Switching. Moving between tasks in either direction. Fails as: cannot leave what you are on, cannot re-enter what you left, the whole morning lost to an interruption at eleven.
Holding. Keeping information live while you use it — working memory. Fails as: losing the thread mid-sentence, forgetting what you came upstairs for, unable to do arithmetic in your head that you could once do easily, losing the plan while executing step two of it.
Most people, asked to distribute their difficulty across these, find it is not evenly spread. And the distribution is informative.
Why the distinction earns its keep
Because the patterns point in different directions. Some rough associations, offered as orientation rather than diagnosis:
- Difficulty with starting and switching, long-standing, across settings, is one of the more characteristic ADHD descriptions.
- Difficulty with holding, new and progressive, is the pattern that most warrants a proper workup rather than reassurance.
- Difficulty with sustaining that arrived recently, alongside low mood, poor sleep or a specific stressor, more often reflects the stressor, the sleep, or the mood — all of which are treatable, and none of which are helped by treating attention in isolation.
- Difficulty with filtering that is new is worth mentioning specifically; it has a different set of associations from the others.
None of these mappings is a rule and none of them is a diagnosis. The point is only that the five are different questions, and collapsing them into "focus" discards the information that would decide which one you are being asked.
Time of day is part of the description
The same capacity can be intact in the morning and gone by three. That is not a footnote; it is one of the most clinically useful things you can report, because it distinguishes a capacity that is impaired from one that is depleted.
"I cannot sustain attention" and "I can sustain attention until about 2pm and then not at all" lead to different conversations. The second is about energy, recovery, sleep, medication duration, and how a day is arranged. The first is about attention.
Writing it down usefully
For a week or two, when something goes wrong, note three things: which of the five, what time, and anything else notable — sleep, dose, whether you had eaten, what the week was like.
That is it. No score out of ten, no rating scale. Just which one, when, and what else was going on.
At the end, you will have something like:
Starting: most mornings, worst when the first task is undefined. Holding: only in the afternoons, and worst on the four days I slept badly. Sustaining and filtering: not really a problem. Switching: bad after any interruption; a meeting at eleven costs the whole morning.
That paragraph is worth more in an appointment than any questionnaire, because it is specific, it is time-stamped, and it was written when it happened rather than reconstructed six weeks later.
Why "I cannot focus" gets a poor response
Not because clinicians are not listening. Because the sentence is compatible with sleep apnoea, depression, ADHD, anaemia, thyroid dysfunction, chronic stress, a medication side effect, grief, and simply being extremely busy — and there is no way to narrow it without the detail.
Supplying the detail does not diagnose you. It does something more useful: it makes the first question a better question.
One caution
Watch the five, then stop watching. There is a version of this exercise that turns into monitoring your own attention continuously, which is itself a distraction and reliably makes everything feel worse. A week or two of notes, then put it away and look at the pattern. The observation is a tool, not a practice.