Free visual tracking game — instant play, no signup, no download
Motion Detector sets a handful of coloured circles bouncing around a dark box. A moment after they start, one circle freezes in place for a fraction of a second while the rest keep moving, then sets off again. Two seconds later everything stops and you tap the circle that paused. Each correct tap moves you up a level, with more circles, faster movement and a shorter pause. It is a detection task, not a tracking one: the circles are all different colours, so you never have to follow one, only notice which one stopped. For the tracking version, where the dots are identical, play Follow the Dot.
Press Start and watch the box. Every circle has its own colour and bounces off the walls in a straight line.
Early in the round one circle, picked at random, stops dead for a fraction of a second while the others carry on.
It then moves again, and all the circles keep going for two more seconds before freezing.
Tap or click the circle that paused. There is no time limit on the answer.
Right moves you up a level; wrong costs one of three lives and replays the level with new positions. Your score is the level you reach.
Levels 1–2 use four circles, levels 3–4 five, levels 5–7 six, levels 8–11 seven and level 12 onwards eight; the circles also get faster and, from level 8, smaller. The paused circle stops for 600, 500, 400, 300 and finally 250 milliseconds, and the pause begins 1.5 s, 1.2 s, 1 s, 0.8 s and 0.6 s into the round. After it moves again, everything runs for two more seconds and freezes.
Tapping the right circle moves you up a level. A wrong circle costs one of three lives and replays the level with new circles. Your score is the level reached, and your best is saved in this browser.
Spotting a brief change among moving objects while your attention is spread across the whole display, then holding onto which object it was for a couple of seconds. The second half matters as much as the first: by the time you answer, the paused circle has moved on, so you have to remember its colour rather than where it stopped. That makes it a cousin of Which Changed, which tests the same kind of change detection on still pictures. It is practice at this task, not a proven way to sharpen vision or driving. Another tracking game to try next: Cup Shuffle. Every game in this family is on the visual tracking games page.
Keeping track of several moving objects at once has been studied since 1988, when Zenon Pylyshyn and Ron Storm showed that people could follow up to five targets among ten identical, randomly moving objects — more than a one-at-a-time attention spotlight should allow — and proposed that the visual system can index a small number of objects in parallel.
Motion Detector removes the hardest part of that task, because its circles all differ in colour, and asks a different question: which object briefly stopped? The stop is short and comes early, so the skill is spreading attention across the whole display and then holding one colour in memory. Reviews of brain-training research find that practice improves the trained task far more reliably than anything outside it.
Remember the colour, not the place. The circle that paused keeps moving for two seconds afterwards, so its position when you answer tells you nothing.
Fix your eyes near the centre of the box and take in the whole field at once. Chasing individual circles with your eyes means the pause often happens behind your gaze.
Name the colour the instant you see the stop — "pink" — and repeat it until the circles freeze. Two seconds is long enough to lose an unrehearsed colour.
Be ready from the very first frame. The pause comes 1.5 seconds into the round at level 1 and only 0.6 seconds in from level 12.
If you missed the stop, still answer: a guess costs the same life as a wrong answer, and there is no timer to beat.
Levels 1–2: four circles. Slow movement, a pause 1.5 seconds in that lasts 0.6 seconds. Use these rounds to practise the colour-naming habit rather than relying on watching the stopped circle.
Levels 3–4: five circles. A little faster, and the pause shortens to 0.5 seconds, 1.2 seconds in. Keep your eyes still; the stop is easier to catch in the corner of your eye than by scanning.
Levels 5–7: six circles. Speed rises again and the pause is 0.4 seconds, one second into the round. Six colours is where people start confusing similar ones such as orange and yellow, so name them precisely.
Levels 8–11: seven circles. The circles shrink and the pause drops to 0.3 seconds, 0.8 seconds in. Settle your gaze before you press Start, because there is little time to get ready.
Level 12 and up: eight circles. The smallest, fastest circles, a pause of a quarter of a second, and it arrives 0.6 seconds after the round starts. At this point the whole game is the first second: see the stop, name the colour, wait.
No. Every circle is a different colour, so you only need to notice which one stopped and remember its colour until the circles freeze.
0.6 seconds on levels 1 and 2, then 0.5, 0.4 and 0.3 seconds as you climb, and a quarter of a second from level 12.
You lose one of your three lives and the same level replays with new positions and a new paused circle. Three wrong answers end the game; your best level is saved in this browser.
The circles move a fixed distance on every screen refresh, so on a 120 Hz display they travel faster than on a 60 Hz one. The pause lengths are timed in milliseconds and do not change.
Follow the Dot uses identical dots, so you have to keep your eye on one target the whole time. Here each circle is distinct and the challenge is catching a brief stop.
There is no good evidence that practice at a game like this carries over to driving or everyday vision. You will get better at this game.