Spot

What it is

Spot isolates one of the most basic things your visual system does: registering where something is. A single dot appears in a square field for a fraction of a second, then disappears. Your job is to mark the exact spot it occupied, from memory.

It is the sixth dimension in the Senso collection, and a deliberately different one. The other games ask what (a colour, a pitch) or how much (a duration, a quantity, an angle). Spot asks where — a question handled by a separate, specialised part of the brain, and one we tend to over-trust.

Because the dot is shown only briefly and then removed, you cannot simply point at it; you have to hold its location in mind and reproduce it. That small delay is where the interesting errors live.

How to play

Tap to begin the round. A dot flashes in the field for about seven tenths of a second, then vanishes. Watch carefully but do not move your cursor yet — the goal is to remember, not to track.

Once the field is empty, tap or click where you believe the dot was. You can drag to fine-tune, or nudge with the arrow keys (hold Shift for larger steps), then press Lock in to commit.

After five rounds you get a total out of 50, with each round showing the true position beside your guess so you can see your personal bias — many people drift toward the centre.

The science

Vision is split into two broad streams. The ventral or "what" stream (down into the temporal lobe) identifies objects; the dorsal or "where" stream (up into the parietal lobe) encodes location and guides action. Spot probes the dorsal stream and the spatial working memory that briefly stores a location after it disappears.

That memory is precise but not perfect, and it is biased in a predictable way. The category-adjustment model (Huttenlocher and colleagues) shows that when we are unsure of an exact position, we unconsciously blend it with the prototype of the region it fell in — often pulling remembered points toward the centre of a quadrant or the middle of the field. Your per-round breakdown will often reveal exactly this inward drift.

Precision also decays with time and competition. Even a short delay, or having to remember more than one location at once, widens the spread of errors — spatial working memory has limited resolution and capacity. Where you happened to be looking matters too: we localise most accurately near the point of fixation, and less well in the periphery.

None of this is a flaw so much as a strategy. The brain stores a compressed, gist-plus-detail representation of space rather than a pixel-perfect snapshot, trading a little accuracy for speed and robustness. Spot makes that trade-off visible.

Scoring explained

Each round is scored on the straight-line (Euclidean) distance between the true dot and your mark, measured as a fraction of the field's width. Landing exactly on the dot is zero error and a perfect 10; the score then follows Senso's shared curve, halving every time the distance grows by the half-score amount.

For Spot the half-score distance is about twelve percent of the field — miss by that much and you still earn a respectable 5 out of 10. Five rounds add up to a maximum of 50. Because people are genuinely good at spatial memory, strong scores here tend to be a little higher than in the trickier senses.

Tips to improve

• Fixate the dot the instant it appears rather than letting your eyes wander — you localise best near where you were looking.
• Anchor the position relative to the field's edges and centre ("upper third, just right of middle") instead of as a free-floating point.
• Resist the pull toward the centre; if you feel unsure, your true memory is usually a bit more extreme than your first instinct.
• Commit quickly. The longer you deliberate, the more the remembered location decays and drifts.
• Use the arrow keys for the final pixel of adjustment once your tap is roughly right.

FAQ