Grid Pattern Span Task

Pattern span holds a static pattern, seen at once and recalled in any order. The Corsi Block-Tapping Test holds a path instead: blocks light one at a time and are tapped back in order. The two spans come apart in patients with brain lesions and under different kinds of interference (Della Sala and colleagues 1999), and memory for patterns develops apart from memory for movement sequences in children (Logie and Pearson 1997), so running both separates visual from spatial-sequential memory.

Each grid shows empty for 1 second, then with its pattern for 3 seconds (1 to 5 in the settings), then empty again for the answer, with no time limit; Done is ready once as many squares are marked as were dark, and a square chosen again is unmarked. Every grid has the smallest shape of at least twice its dark squares that keeps the squares at least 44 pixels wide on a phone, so exactly half the squares are dark except at 7, 11, 13 and 14 squares, where a few more are light. Two practice grids, of 2 and 3 squares, end with the pattern shown again and whether it was marked right. A setting gives 2 grids at each size in place of 3. Naming parts of a pattern can help (Brown, Forbes and McConnell 2006), so the patterns are random rather than chosen to be hard to name.

The main score is the span: the most dark squares in a grid reproduced exactly. The task also reports the grids reproduced over all sizes, the share of dark squares marked (partial credit for grids not reproduced), the largest size shown and the time to answer. Scores support research and do not diagnose.