It's one of the most confusing things about ADHD. A person can lose four hours to a video game, a project or a rabbit hole online, then fail to open a single email. People around them say, "You can focus when you want to." The person usually feels the same confusion, and often a lot of shame. This guide explains the puzzle in plain words, what research says, what else can affect focus and what helps. It doesn't tell you what you have.
This article is general information, not a diagnosis. Only an assessment by a qualified clinician can say whether ADHD fits.
The puzzle, focus on some things and not on others
Many people picture ADHD as a shortage of attention. If that were true, nobody with ADHD could ever focus for long. Yet many adults say they can sink into something they love for hours.
That's why some researchers and many people with ADHD prefer to talk about attention that is hard to steer, not attention that is missing. In one qualitative study, young adults with ADHD described struggling with attention dysregulation, including hyperfocusing, along with emotional dysregulation. The study's title says it well: "Dysregulated not deficit."
This is also why "just try harder" so often fails. The problem is rarely how much someone cares. It's how hard it is to point attention where it needs to go.
What many people say about how their attention works
NIMH describes ADHD as a pattern of inattention, and sometimes hyperactivity and impulsivity, that is frequent, shows up in more than one setting and interferes with daily life. NIMH adds that for some people, inattention is the strongest area.
In everyday terms, many people with ADHD describe attention that follows certain things:
Interest. Something they find fascinating pulls them in without effort.
Urgency. A deadline that's suddenly close can finally get them moving.
Novelty. New things feel exciting, and the same old task can feel flat.
Reward. A task that gives quick feedback is easier than one with a payoff far away.
These are descriptions, not rules. They aren't official signs, and people vary a lot. But they explain why a boring but important task can feel so much harder than a hard but fun one.
What research says about interest and reward
Scientists are still working out why this happens. One brain imaging study of adults found lower function in the brain's dopamine reward pathway in adults with ADHD. The researchers linked it to lower motivation scores, and they described this as a possible explanation, not a settled one. It was a single study, so it should be read with care.
The idea fits what many people report. When a task isn't rewarding in the moment, it can be very hard to start and stay with it. When it is, attention seems to arrive on its own.
Hyperfocus, the part people misread
Hyperfocus is a state of very deep concentration, when a person loses track of time and the world around them. A 2019 study noted that adults with ADHD often report long stretches of highly focused attention, which can seem surprising given how easily they're distracted by other things. The researchers found that people with higher levels of ADHD symptoms reported more hyperfocus in school, hobbies and screen time.
It's important to say what hyperfocus is not. It isn't one of the symptoms NIMH lists for ADHD, and the researchers suggest it may be worth studying as its own feature. It can also cost something. Meals, sleep, messages and other duties can slip away while a person is deep in a task.
This is why seeing someone focus on a game doesn't mean they can "choose" to focus on homework or a report. The two kinds of attention aren't the same thing. Switching out of hyperfocus can also be hard. Some people describe feeling jolted or irritable when they're interrupted, which can lead to arguments at home or work. A heads-up before an interruption, such as a gentle call from the doorway, can soften it.
What it can feel like to be told "you can focus when you want to"
Hearing "you can focus when you want to" can sting. It treats focus as a switch that a person is choosing to leave off. Most people with ADHD describe it very differently. They say they would love to start the task, and they can't make the start happen.
Over time, this can lead to shame, a sense of failing at simple things, or a belief that something is wrong with their character. That's one reason the focus puzzle matters. When people understand how attention can work differently, they can swap blame for curiosity and better plans.
If you're reading this for someone you love, try asking, "What would make starting easier?" instead of "Why can't you just do it?" The question shifts the conversation from judgment to problem-solving.
When it might be something else
Trouble focusing has many causes. ADHD is one possible explanation, and it isn't always the right one. Here are some other things that can make concentrating harder:
Low mood or depression. CAMH lists trouble concentrating among the symptoms of depression.
Anxiety. A mind full of worry has less room for the task at hand.
Poor sleep. NIMH notes that sleep problems are especially common in adults with ADHD, and tired people struggle to focus whether or not they have ADHD.
Stress or burnout. Too much for too long can leave anyone foggy.
NIMH also notes that ADHD often occurs along with other conditions, such as anxiety, depression and sleep problems, which can make each harder to spot. That's why guessing isn't reliable. A good assessment looks at all of it and helps you find out what's behind your focus.
Practical supports that don't rely on willpower
Nothing here is medical advice, and none of it is a treatment. These are everyday ideas many people find helpful when attention is hard to steer. Pick one or two to try, not all at once, and drop whatever doesn't fit your life.
Shrink the first step. Instead of "write the report," try "open the file and write one sentence."
Use timers. A short timer, such as 15 minutes, can make a dull job feel less endless.
Try body doubling. Some people focus better when another person is nearby, even if they're doing something else.
Add a little interest. Music, a new location or a small reward after a step can help a boring task feel less flat.
Make deadlines visible. Put the real due date, and a start date, on a calendar you can see.
Plan for hyperfocus. Set an alarm before you start something absorbing, so meals and sleep don't disappear.
Starting is often the hardest part, and some people find that once the first step is done, the rest flows more easily. If it doesn't, that's information too. Our article on why we procrastinate looks at the stuck feeling from another angle. If shame is part of the picture, you're not alone. It's common after years of hearing "try harder."
What an assessment involves
If you wonder whether ADHD is behind your focus, an assessment can bring clarity. NIMH explains that diagnosing adult ADHD relies heavily on past reports of behaviour, and can include interviews, rating scales and psychological tests. A psychologist may also look at whether something else is behind what you've noticed.
Our psychologists assess and diagnose, and our Nurse Practitioners assess, diagnose and prescribe. You can read about our adult ADHD assessment in Kitchener-Waterloo. Our guide to the assessment process in Ontario walks through what to expect. Assessment fees depend on the service, and we go over them with you in your free consultation.
For day-to-day support, Registered Psychotherapists (RPs) and Registered Social Workers (RSWs) provide therapy. Individual sessions are $130 to $200, and student therapists offer sessions for $0 to $80. If you're curious about medication, raise it with your prescriber or ask about our Nurse Practitioners, and don't stop anything on your own.
If low mood or hopelessness is part of what you're feeling, call or text 9-8-8 any time.
Start with a free conversation
You don't have to be sure to ask a question. Book a free 15-minute consultation to talk about your focus and what an assessment would involve. We don't have a waitlist. We see clients in person in Waterloo, Kitchener, Cambridge and Ottawa, and online across Ontario. No referral is needed, and evening and weekend appointments are available.