I came across this issue a couple of times and I decided to make a blog-post reminder for my personal glossary.

The “Mida’s Touch” problem refers to the fact that the eyes cannot be used directly as a mouse, because the eyes are never “off.” Thus one of the main problems when using the eye-gaze for selection purpose is to somehow combine it with a “clutch” that can engage/disengage eye-gaze control. A good clutch should be quick to operate, not increase the cognitive load unnecessarily and not disturb the user’s gaze-pattern, because the user will often be looking at some object when she wants to engage eye-tracking, and it would thus slow down the communication if she had to move her eyes to do it.

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