Insights into Rapid Eye Movement during Sleep

Article: Our eye movements reveal our emotions during sleep
Source: Paris Brain Institute, Sorbonne University (France)
Published: February 16, 2022

Slow eye movements were associated with positive emotions during dreaming,
while negative emotions were never associated with them

It is well-known that rapid eye movements (REMs) occur during dreaming, while the rest of the body is paralyzed during a stage of sleep called REM sleep. However, what rapid eye movement indicates is poorly understood and supporting evidence indirect. Some researchers have hypothesized that rapid eye movement follows the dream scenario, similar to how the eyes would move when awake. Others proposed that rapid eye movement is linked to reactivation of emotional memory during dreaming, and some studies have shown that rapid eye movement is more frequent in REM sleep of people suffering from or at risk of depressive disorders, suggesting an association to regulation of mood and emotions. Investigators in France studied the link between REM sleep and emotions during dreams through observations of 20 participants with REM sleep behavior disorder. In this case, the participants' emotions during dreaming are revealed in their facial expressions, speeches, or other behaviors. Senior author of the study comments, "Thanks to them, we have direct access to the emotional content of the dream." Using video and electro-oculography recordings, the researchers observed that positive behaviors were associated with slow eye movements (SEMs) (OR = 2.8) while negative behaviors increased with isolated REM activity (OR = 2.6) and especially with REM bursts (OR = 10.1). Slow eye movements were never linked with negative behaviors/emotions. Sleep behavior disorders could be considered an extreme manifestation of the more typical rapid eye movements that every one of us experiences during dreaming, and thus more easily demonstrate insights about the neurology of the general population. The researchers conclude, "These results support an association between REMs and SEMs, and dream emotions."

My rating of this study: ⭐🌸

Maranci JB, Nigam M, Masset L, et al. "Eye movement patterns correlate with overt emotional behaviours in rapid eye movement sleep." Scientific Reports. 12:1770. 2 February 2022.
https://doi.org/10.1038/s41598-022-05905-5