Investigation on neurobiological mechanisms of dreaming in the new decade

Dream research has advanced significantly over the last twenty years, thanks to the newapplications of neuroimaging and electrophysiological techniques. Many findings pointed out thatmental activity during sleep and wakefulness shared similar neural bases. On the other side, recentstudies have highlighted that dream experience is promoted by significant brain activation,characterized by reduced low frequencies and increased rapid frequencies. Additionally, severalstudies confirmed that the posterior parietal area and prefrontal cortex are responsible for dreamexperience. Further, early results revealed that dreaming might be manipulated by sensorystimulations that would provoke the incorporation of specific cues into the dream scenario.Recently, transcranial stimulation techniques have been applied to modulate the level ofconsciousness during sleep, supporting previous findings and adding new information aboutneural correlates of dream recall. Overall, although multiple studies suggest that both the continuityand activation hypotheses provide a growing understanding of neural processes underlyingdreaming, several issues are still unsolved. The impact of state-/trait-like variables, the influence ofcircadian and homeostatic factors, and the examination of parasomnia-like events to access dreamcontents are all opened issues deserving further deepening in future research.