CONCEPT
Forty-Seven Seconds
Gloria Mark 's empirical measurement of the average duration a knowledge worker sustains attention on a single screen — down from two and a half minutes in 2004, and the number that anchors her AI-era diagnosis.
Forty-seven seconds is the empirical finding that crystallizes two decades of Mark's observational research on knowledge workers. Obtained through painstaking shadowing, task logging, and second-by-second measurement, it describes how long the average person now sustains attention on a single screen before switching. The trajectory — from 150 seconds in 2004 to 47 seconds by the early 2020s — predates the AI revolution but is accelerated by it. The number's power lies not in drama but in its resistance to narrative: it describes what is measurable, regardless of what workers believe about their own focus. In the AI-augmented workflow, where pauses between engagements shrink toward zero, the floor threatens to drop out entirely.
In The You On AI Field Guide
The number emerged from Mark's methodology of direct field observation rather than self-report. Workers shadowed by her research team consistently described themselves as focused for long stretches, occasionally distracted. The measurement showed something else: fragmentation at a cadence the workers