Meta-analysis of brain functional images under N-back and DMTS paradigm in human working memory

Objective To study the similarities and differences in brain activation under N-back and DMTS paradigms of working memory. Methods Through searching of BrainMap function database by the combination keywords, a total of 122 articles with 122 experiments (N-back: 67 experiments, 937 subjects, 900 foci; Delayed Matched to Sample: 55 experiments, 806 subjects, 872 foci). Maps were analyzed using the FDR PN (P<0.0001) method based coordinates of the Montreal Neurological Institute (MNI) space. Results In the combine of the N-back and DMTS paradigms, these regions were activated including the bilateral inferior parietal lobe (Left: -36, -52, 44; Right: 38, -52, 48) and insula(Left: -34, 22, 0; Right: 34, 24, 2), the superior frontal gyrus (2, 16, 50) and inferior frontal gyrus (-44, 8, 30)of the left brain, and the middle frontal (46, 36, 24) and sub-gyral (30, 4, 56)of the right brain. The N-back paradigm was similar to the above results, whereas the DMTS paradigm only activated the precentral gyrus (-50, 8, 34) of the left brain and the right insula (34, 24, 4). Conclusion The neural circuit of working memory is the frontal-parietal networks. N-back paradigm with the brain activation consists to the neural circuit of working memory.However, DMTS paradigm activates less brain regions and is inconsistent to the neurons of working memory. Key words: Health controls; Working memory; N-back paradigm; Delayed matched to sample paradigm; Meta-analysis; Brain functional images