The Change Blindness Test rules run on a fixed five-round state machine that scores exactly 1,000 points for a perfect finish. Each round shows an Original abstract scene for 900 milliseconds, then a neutral blank mask for 180 milliseconds, then a Changed frame divided into nine numbered zones. The player studies the Original carefully enough to know which feature is about to shift, waits through the brief blank, and identifies the changed zone by clicking or by pressing a number from 1 through 9. A correct zone adds 200 points, the next Original frame appears, and the cycle repeats for five trials. Any incorrect zone opens the error budget, and a second different wrong zone ends the run in a terminal deadlock. Knowing those exact timings, zone positions, and error rules is what separates a random first guess from a deliberate 1,000-point finish on the Change Blindness Test.
Because every detail is fixed and disclosed, the rules read more like a short technical contract than a guessing game. The five scenes are abstract SVG fixtures with named features — rings, squares, rays, stripes, orbit dots, bridges — and each round changes exactly one of those features while every other element stays pixel-identical. The answer grid, the timers, the scoring, and the dead-end conditions are all explicit, which means a careful reader can plan the run instead of relying on luck.
What the Change Blindness Test Rules Actually Define
Three separate conditions control every round: the visual state machine that drives what is on screen, the scoring formula that rewards a correct answer, and the error rules that decide when the run ends. Those three layers are independent and never overlap. The timer runs the presentation, the score updates only on a correct answer, and the error counter tracks only the round-and-zone signature of each wrong pick. None of those layers speak to one another, which is why the rules can stay both simple and strictly enforceable.
The Original stage always lasts 900 milliseconds unless the player shortens it, the Flicker always lasts 180 milliseconds and cannot be skipped, and the Answer stage stays open indefinitely until the player presses or clicks a valid zone. There is no overall round timer, no time limit on the Answer phase, and no penalty for thinking slowly during the Changed frame.
The Five Round-by-Round Changes
Each round draws from the same stable geometry and changes one declared feature. The feature list is part of the ruleset, so a reader can verify which zone will be correct on the first try. The table below pairs each round with the feature that moves and the cardinal direction that anchors it inside the 3-by-3 zone grid.
| Round | Feature that changes | Where it sits |
|---|---|---|
| 1 | Central ring becomes a square | Center zone (5) |
| 2 | Northwestern ray cluster reduced | Top-left zone (1) |
| 3 | Southeastern stripe set rotated | Bottom-right zone (9) |
| 4 | Dot in the northeastern orbit moves | Top-right zone (3) |
| 5 | Gap opens in the southwestern bridge | Bottom-left zone (7) |
Those five before-and-after pairs are the entire content of the game. Once the player has seen the Original frame long enough to register the named feature, the only remaining decision is to identify the correct 1-based zone. Every other element on screen is preserved between Original and Changed, so a wrong pick almost always comes from misreading the zone map rather than from missing the change itself.
Zone Map and Keyboard Layout
The answer layer is a transparent 3-by-3 grid that covers the entire Changed frame. Each cell becomes one large semantic button, and the buttons are numbered in reading order: 1 in the top-left corner, 3 in the top-right, 7 in the bottom-left, and 9 in the bottom-right. Zone 5 always covers the center, regardless of which feature happens to live there.
| Number | Grid position | Typical round example |
|---|---|---|
| 1 | Top-left | Round 2 (northwestern ray cluster) |
| 2 | Top-center | — |
| 3 | Top-right | Round 4 (northeastern orbit dot) |
| 4 | Middle-left | — |
| 5 | Center | Round 1 (central ring becomes square) |
| 6 | Middle-right | — |
| 7 | Bottom-left | Round 5 (southwestern bridge gap) |
| 8 | Bottom-center | — |
| 9 | Bottom-right | Round 3 (southeastern stripe set) |
Pointer and touch users click directly inside the changed region, which is the same as tapping the matching zone. Keyboard users can press the matching number key without needing precise pointer movement. The number route is a primary input, not a fallback, so the game stays fully playable without a mouse, and every answer zone exceeds the minimum touch target for tap-friendly play.
How to Score 1,000 in Five Rounds
The 1,000-point finish is the result of five correct zone choices, each worth 200 points, with no speed multiplier attached. To complete the run on purpose, work through the following steps:
- Study the Original abstract scene for the full 900 milliseconds, or press S to end the Original stage early. Use the Original window to register which named feature — the central ring, a ray cluster, a stripe set, an orbit dot, or a bridge — sits in the area you expect the change to occur.
- Wait through the 180-millisecond neutral mask without clicking or pressing any number. The mask is always 0.18 seconds long. Show change now only shortens the Original stage; it never shortens or skips the mask.
- When the Changed frame appears, locate the single visible change and identify its zone number from 1 through 9. The grid follows reading order, so top-left is 1, top-right is 3, bottom-left is 7, and bottom-right is 9, with 5 in the center.
- Click the changed zone with the pointer, or press the matching number key. The answer layer only accepts input during the Answer stage; clicks or number presses during Original or Flicker are treated as harmless no-ops.
- Confirm the 200-point addition and let the next Original frame load. Each correct zone adds exactly 200 points and starts the next round in the Original state. There is no speed bonus and no penalty for slow answers during the Answer stage.
- Repeat steps 1–5 for all five rounds. Five correct answers equal 5 × 200 = 1,000 points exactly. The run closes in the completion state and the score is saved as the new best if it beats the previous best stored in this browser.
Because each round only ever changes one declared feature and the geometry is otherwise stable, the step list works equally well on the first round or the fifth. The math is straightforward: 200 points per round, five rounds, no multipliers, no adjustments, no random targets — a perfect run always lands on 1,000.
Misses, Repeats, and the Deadlock Rule
The error counter is keyed by round and zone, not by the total number of clicks. The first wrong pick in a round opens a one-miss budget and is recoverable, and choosing the same wrong zone again is recognized as a repeat and does not consume the second error. The run only ends when the player picks a different wrong zone within the same round, which records a second distinct signature and closes the game in a terminal deadlock.
Invalid inputs follow the same pattern. Out-of-range numbers, answers submitted before the Changed phase, and any action taken after completion or after deadlock are harmless no-ops that leave the state untouched. This is why a player can mash the number pad by accident without ending the run early; only a deliberate second distinct wrong pick can do that. The independent logic test repeats one wrong zone to confirm it does not trigger deadlock, then triggers a second distinct miss to confirm the run freezes exactly where the rules say it should.
Show Change Now and the Mask It Cannot Skip
The Show change now button, and the S key, both shorten only the Original stage. They never shorten or skip the 180-millisecond neutral mask, and they never start the Answer phase directly. The mask is preserved because its job is to remove the Original frame from the screen before the Changed frame appears, which is the entire point of a change-blindness trial. Skipping the mask would turn the round into a side-by-side comparison and break the experiment the game is built around.
After Show change now fires, the round transitions to Flicker for the full 180 milliseconds and only then mounts the Answer layer. Reduced-motion users, pointer users, and keyboard users all experience the same transition sequence; the shortcut is presentation-only and does not change scoring or alter the dwell time the Answer stage allows.
Controls, Score Persistence, and the Boss Key
The visible focus ring, large semantic buttons, and live feedback make the state understandable without relying on color alone. Restart restores trial one, zero points, two available errors, and the complete Original timer. The best completed score persists in this browser only, and only the shared best score is stored — there is no upload, no account, no third-party request, and no camera or eye tracker. Double-press Escape opens a simulated spreadsheet boss screen; double-press it again to resume the unchanged trial.
For readers who enjoy similar visual comparison games with disclosed rules and fixed fixtures, the Spot the Difference challenge pairs two side-by-side harbor scenes in the same browser-only format and rewards a clean visual sweep with a comparable five-change scoring route.
What the Change Blindness Test Rules Do Not Cover
The rules are explicit about scope. The game makes no claim about eyesight, cognition, attention health, or any clinical ability, and the abstract scenes are original product fixtures rather than photographs, scientific stimuli, or imported perception tests. There is no speed multiplier, no random target, no adaptive difficulty, no timer penalty, and no hidden score adjustment — the short timers control presentation only, not how many points a correct answer earns.
For other fixed visual challenges that publish their scoring in the same transparent way, the Pattern Memory Game asks players to memorize original 3-by-3 patterns and choose each hidden record from four options, while sibling comparison and recall tools like the Hidden Object Game and the Visual Memory Test follow a similar fixed-fixture rule style. Comparing those contracts side by side is the cleanest way to see how different rule sets translate into different scoring strategies while keeping the underlying presentation philosophy — transparent fixtures, deterministic scoring, browser-only state — fully consistent.