Vigilance Decrement: A Signal-Detection Radar Watch (2D)

Sustained attention is not a flat resource — psychologists have known since Mackworth's WWII-era radar studies that an observer's ability to catch rare, important signals fades measurably within the first 20-30 minutes of watching a quiet display. This 2D companion turns that finding into a real task you actually play: watch a radar scope, click whenever a bright target ring appears among the far more common dim distractor dots, and a genuine signal-detection-theory scorer classifies every response as a hit, miss, false alarm or correct rejection. A fatigue curve quietly fades the target's visibility over the course of the shift exactly as the vigilance-decrement literature describes, so your own measured hit rate erodes and your measured criterion drifts more conservative — no scripted numbers, just the real, well-documented mechanism behind why air-traffic control, quality inspection and security monitoring all fight the same fundamental cognitive limit.