Have you ever woken from a dream speaking or acting out part of your dream?
A dream-enacting behavior (abbreviated DEB) is a history of recurrent nocturnal dream, which typically occurs during transitions from dreaming to wakefulness.
The most common Dream Enacting Behaviors include speaking out, crying/sobbing, smiling/laughing, expressing bodily fear (i.e. jolting or tension), and anger/defensive behavior. These behaviors occur especially after particularly intense dreams, such as nightmares, or also very sad, angry, or even erotic dreams.
One interesting finding about DEB, is that they may reflect the speech or actions of both the dreamed self, or another dreamed figure. For example, if you dream of being chased by a growling monster, you could wake up trembling in fear, or you could wake up growling, as if you were the monster.
The finding demonstrates a phenomenon inherent to dreaming that we are often unknowed: all of the characters within a dream, are simultaneous creations of your mind. Your dreaming mind has the capacity to at once dream from a self-perspective, while also juggling a multitude of other characters and attributing each their own respective feelings, distinct voices and speech patterns.
How do the mind administrate this multiplicity of dream figures?
One possible explanation is that the mirror neuron system is responsible for constructing distinct dream figures. Neuroimaging studies have shown that the same brain areas are activated both while performing a specific action oneself (e.g. grasping something), and while observing that action in another (e.g. seeing a friend grasp something).
In general, the mirror neuron system may allow us to understand the actions and emotions of others during wake, but perhaps also during dreaming.
The authors of one recent study (Nielsen and Kuiken, 2013) developed a Mirror Behaviors Questionnaire (MBQ) in order to measure the most common behavioral manifestations of mirror neuron activity, such as contagious crying, laughing, motor mimicry, and others. They aimed to test whether mirror behaviors during waking were related to Dream Enacting Behaviors during sleep.
The authors found that individuals who expressed more mirror behaviors while awake, also expressed more dream enacting behaviors during sleep; in fact total scores on the MBQ and DEB were significantly correlated. The most striking relationship was found for emotional contagion items, including crying, smiling, and laughing. Therefore the work suggests that the mirror neuron system underlies our mental capacity to create and maintain multiple independent dream characters, in a way that represents our fellow human beings in real life.