🧠 Most effective working memory trainer (Jaeggi et al., 2008 — the only paradigm with proven IQ transfer effect). 📋 HOW TO PLAY: • Cells flash on the grid one at a time • Remember the position N steps ago • When current flash MATCHES the position from N steps back → press MATCH • If it doesn't match — don't press, wait for next 🎯 EXAMPLE for N=2 (track positions 2 steps back): Step 1: flash top-left → wait Step 2: flash right → wait Step 3: flash bottom-left → COMPARE with step 1 (top-left). Doesn't match → don't press Step 4: flash right → COMPARE with step 2 (right). MATCH! → press ✓ 💡 STRATEGY for beginners: • Start with N=1 (track just the previous flash) until rhythm clicks • Then N=2, then N=3. Above N=4 is elite-level • Don't try to "remember all steps" — your brain runs a sliding window automatically • 15-20 min/day for 3-4 weeks → noticeable WM gains