To　investigate　the　role　of　mental　imagery　during　heuristic　problem　solving,　we　took　4x4　sudoku　as　a　new　paradigm　in　this　study.　There　were　two　experimental　conditions,　one　was　split　meant　participant　needed　to　integrate　Sudoku　information　of　two　parts,　and　the　other　was　no　split　meant　participant　could　solve　the　problem　directly　without　integration.　Based　on　the　theory　of　ACT-R　(adaptive　control　of　thought-rational)　model,　five　key　brain　areas　were　analyzed.　The　result　showed　that　regions　of　left　Fusiform　gyrus　(LFG),　bilateral　Prefrontal　Cortex　(PFC),　and　Posterior　Parietal　Cortex　(PPC)　were　involved　in　the　process　of　mental　imagery.　And　the　further　functional　connectivity　analysis　showed　that　the　correlations　between　PPC　and　PFC　as　well　as　PPC　and　LFG　was　significantly　increased　in　the　condition　of　split.　The　results　suggested　that　except　for　the　region　PPC　played　a　key　role　for　the　processing　of　mental　imagery,　the　association　of　PPC　with　other　regions,　such　as　FG　and　PFC　would　improve　the　mental　imagery　during　heuristic　problem　solving.　©　Springer　International　Publishing　2013.