Odd One, find the only T

What it asks of you

Odd One asks for careful visual search. A T and an L are made of the same two strokes, only the joint differs. Nothing pops out, so your eyes have to check square after square.

That is the kind of search you do when you look for a typo, a face in a crowd or your keys on a busy desk.

How to play

1. A 3 by 3 grid of Ls appears, each one turned a quarter turn at random.
2. One square holds a T, so find it and tap it.
3. Each find brings a new grid. After 3 finds it grows to 4 by 4, after 6 to 5 by 5.
4. A tap on an L counts as a miss.
5. Twenty seconds. Your score is the Ts you found minus your misses.

The research behind it

In 1980 Anne Treisman and Garry Gelade showed that a target set apart by one simple feature, a color or a shape, pops out at once, while a target that shares its features with its neighbours has to be searched item by item (Treisman and Gelade, 1980). A T among Ls is that second kind of search.

That makes Odd One a pure search workout. Practice on a search task makes you faster at that task (Simons et al., 2016), and the steady sweep it asks for is a skill you build round after round.

On your weekly card

Odd One is a lab game, in free play in the game room of the app.

It is never graded and has no published norm for this format, so your own best is the reference.

Questions

Why is the T so hard to find?

Because it shares its strokes with the Ls. Only the way they meet differs, so the T never pops out and you must check each square (Treisman and Gelade, 1980).

Does the grid always grow?

Yes, with your finds. 3 by 3 at first, 4 by 4 after 3 Ts, 5 by 5 after 6.

Why do misses count?

Tapping everywhere would beat searching. Taking misses away keeps the score about real search.

Sources

1. Treisman A.M., Gelade G. (1980). A feature integration theory of attention. Cognitive Psychology 12(1), 97 to 136. doi.org/10.1016/0010-0285(80)90005-5
2. Simons D.J., Boot W.R., Charness N. et al. (2016). Do brain training programs work? Psychological Science in the Public Interest 17(3), 103 to 186. doi.org/10.1177/1529100616661983