A path tracing memory test, based on the Corsi block-tapping task, shows a route across a grid and asks you to retrace it in the same order. In this free online version the grid grows from 3x3 to 7x7 and each level adds one step, so it measures your spatial span.
During each trial, an animated target illuminates across a sequence of matrix coordinates at standardized 500 ms intervals. Users must encode both spatial coordinates and temporal order, then faithfully retrace the entire route in exact chronological sequence during 60 seconds of active tracing time; path demonstrations are untimed.
In working memory architecture, Logie (1995) and Alan Baddeley (2000) identified that sequential movement is retained by the Inner Scribe, a dynamic spatial rehearsal loop. George A. Miller (1956) and Herbert A. Simon (1974) proved that sequential performance hinges on directional chunking, while Nelson Cowan (2001) established that unassisted focal working memory is limited to roughly 4 items.
Standardized normative studies on computerized Corsi block tasks (Kessels et al., 2000) established the healthy adult forward spatial span at 5.4 ± 0.9 steps, showing that sequential retention is highly sensitive to cognitive fatigue, sleep, and executive function.
How this is measured: every event is timestamped with the browser's performance.now() high-resolution clock, entirely on your device -- no score is uploaded. Browser timers are deliberately coarsened as a Spectre mitigation (typically to about 1 ms), and your display quantizes each change to its refresh interval, about 16.7 ms per frame at 60 Hz (Woods et al., 2015). Treat differences smaller than about 5 ms as measurement noise, and compare your own runs on the same hardware rather than against someone else's setup.
Data transparency: SkillDrills collects no aggregate data. Your scores and settings live only in your browser's localStorage and are never uploaded, so this site publishes no user averages, percentiles or player counts. Every figure quoted here comes from the published work in the References panel below.
This drill is a free browser game for practice and interest. It is not a medical device, a diagnostic instrument, or a screening or treatment tool for any condition, and no score here says anything about your health or your memory in a clinical sense. If you have concerns about your memory or thinking, speak to a qualified clinician.