Mark Studies Track Attention Spans Shrinking from 150 to 47 Seconds with Digital Device Use

Gloria Mark's sensor-based observations at UC Irvine recorded average attention spans on screens falling from 150 seconds in 2003 to 75 seconds in 2012 and 47 seconds in 2014-2020 cohorts. Heart-rate data linked rapid switches to elevated stress markers and extended task completion times. The MIT Technology Review interview applies these metrics to current AI chatbot interfaces without new measurements. Mark's 2003-2020 living-laboratory protocols, detailed in her publications, relied on direct observation of adult volunteers rather than self-reports. Related 2024 legal settlements against Meta and Google cited product design contributing to youth addiction claims, yet Mark stated evidence on broad child effects remains inconclusive per aggregated studies. Australia's under-16 social media ban, enacted December 2024, initiates one long-term cohort for future comparison. Primary device-tracking findings predate widespread chatbot deployment and do not isolate generative AI variables from email, social platforms, or browsers.