Zehano’s reaction game asks you to wait for a green GO cue and respond. It completes five valid trials and displays the average in milliseconds. That number describes the interaction between you, the task and the device; it is not an isolated measurement of your nervous system.
Wait for the actual signal
Press Start, then wait. Clicking before the cue restarts that trial without recording a time. Avoid guessing the moment from a previous attempt. You can click, tap or focus the button and use the keyboard, but different input methods should not be treated as identical conditions.
Keep comparisons consistent
Use the same device and input method when comparing sessions. Screen refresh, input latency, browser scheduling and distractions can affect a result. A single unusually quick trial may be a poor summary, which is why the activity uses several trials. Do not compare the number directly with a laboratory norm.
Practice without overinterpreting
Becoming familiar with the cue and controls can change your score. That does not establish an improvement in every real-world reaction task. Stop when the game is no longer enjoyable, and choose an untimed puzzle if you prefer. The saved best score is a local game record, not a medical assessment or a measure of suitability for driving or other safety-critical activities.
Updated 10 October 2026. Original practical guide created with AI-assisted drafting and software checks. No professional or clinical review is claimed. Editorial approach and corrections.