Neural dynamics of 3-D object perception assessed by combined MEG/FMRI imaging technique

Here, we used both the neuromagnetic (MEG) and the hemodynamic (fMRI) measures to visualize the spatiotemporal brain dynamics during 3-D structure perception from 2D motion (3D-SFM). The coherence of the random-dot motion stimuli was parametrically controlled to infer the changes of the brain dynamics corresponding to different 3-D percepts. The results of the fMRI analysis were used to impose plausible constraints on the MEG inverse calculation using the dasiaweightedpsila minimum-norm approach to improve spatial resolution of the spatiotemporal activity estimates. The inferior-temporal, the parieto-occipital, and the intraparietal regions showed increased neural activity in the highly coherent motion conditions in which subjects perceived robust 3-D object structure at different latencies. These results are in agreement with the previous fMRI studies and add further insight into the temporal dynamics of the neural activities in the multiple brain regions along both the dorsal and the ventral visual processing streams during 3D-SFM.