Increase in alpha and beta top-down connectivity during visual imagery as compared to perception

By taking advantage of hdEEG and state-of-the-art approaches for assessing directionality of cortical signal flow, our results provide the first clear-cut evidence for increased top-down directional connectivity during visual imagery as compared to visual perception. Future studies will apply this approach to compare brain connectivity patterns during waking and sleep mentation. [1] Cichy et al., Cereb Cortex. 2012: 372-80; [2] Kosslyn et al., J Cogn Neurosci. 1997:26387; [3] Cheung et al., IEEE Trans Biomed Eng. 2010:2122-34; [4] Friston et al., Curr Opin Neurobiol. 2013:172-178; [5] Gardini et al.,. Psychol Res. 2009:633-643; [6] Ganis et al., Brain Res Cogn Brain Res. 2004:226-41; [7] Harrington et al., Hum Brain. 2007:1589-96. Visual imagery was characterized by a reversal of information flow in the parieto-occipital edge, as compared to visual perception.