Melatonin, Dream Recall, and Theta Oscillations: The Cognitive Health Connection
Melatonin supplementation is associated with increased cognitive health including enhanced formation of both short-term [Labban 2021] and long-term [Iwashita 2021] memory. Melatonin is also associated with vivid dreams during REM sleep [Maurizi 1987] and sometimes reports of intense dreams including nightmares.
What is the connection between improved memory and the ability to recall dreams?
Theta Oscillations and REM Sleep
REM (rapid eye movement) and non-REM sleep are the two main phases of sleep, during which electrophysiological patterns including sharp-wave ripples, cortical slow oscillations, delta waves, and spindles are observed during non-REM sleep; whereas theta oscillations are consistently present and observed during REM sleep [Jouvet 1969]. These various types of oscillations represent precisely timed activities of underlying neural circuits.
Theta oscillations [Buzsáki 2002] are manifestations of neural circuits involved in the processing of sustaining memory consolidation during sleep [Girardeau 2021].
Furthermore, the ability to generate dreams and the ability to recall dreams is intrinsically dependent on the development of neural systems, and there is a certain correlation between cognitive skills and specific features of dream reports [Mangiaruga 2018].
The Older You Are, the Less Likely You Will Dream AND Remember Your Dreams
Studies on adults showed common mechanisms between waking cognition and corresponding dream features, as well as a declined ability to recall dreams is reported in the elderly [Giambra 1996][Kahn 1969].
Specifically, spindle density responsible for cognitive functions is also positively correlated with dream recall and visuospatial performance scores in healthy subjects [Nielsen 2017].
Dreaming, is therefore, a potential index for memory consolidation.
The Level of Theta Oscillations Generated During REM Sleep Can Determine How Much You Can Recall Your Dreams
In a study that measured the oscillatory EEG activity during REM sleep in healthy young and elderly subjects found that theta oscillations…