Simon Effect

A blue or orange square pops up on the left or right. Respond to its COLOUR — blue means left, orange means right — and ignore which side it’s on. When colour and side clash, your hand wants to go the wrong way. Fight the pull.

Trains: Response inhibition · Category: Attention & Speed

How to play: Simon Effect is a free, browser-based brain-training game in the Brain Gym suite. Play it instantly — no sign-up, works offline, and your best scores are saved on your device.

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