During REM sleep, dreams are the epitome of living in the moment, of harnessing the power of now. During these dreams, consciousness is concerned solely with the immediate present. Once we awaken, humans—”and supposedly only humans,” according to a German study out in Nature Neuroscience—inhabit a different mode of consciousness that allows higher-order cognitive functions like abstract thinking, volition, and self-reflective awareness.
But sometimes, we humans can have lucid dreams. These dreams take place during REM sleep, but we are aware we are in a dream. We can even control the dream’s plotline.
EEG and fMRI studies have shown that there is elevated activity in what’s called the lower gamma frequency band, notably in frontal and temporal regions of the brain, during lucid dreams. Gamma band activity is modulated by sensory input and internal processes like working memory and attention. It is most often viewed as a byproduct of neural activity; it is not clear if it contributes to brain function.