For most people, voluntary action, critical thinking, and an awareness of the minds present state are either very limited or completely absent while dreaming. Interestingly, however, those engaged in a lucid dream are able to access these metacognitive skills which can then be used to influence the content of their dreams. In a recent study published in the Journal of Neuroscience, Filevich et al. (2015) identified some specific neural mechanisms that may underlie the experience of lucid dreaming. They suggest that lucid dreaming may actually be a particular form of metacognition that utilizes those same neural systems that are present during thought monitoring while awake.
In the first part of the study by Filevich et al. (2015), participants completed a questionnaire that evaluated their ability to engage in lucid dreaming. Next, the participants were divided into two groups based on their scores from the lucid dreaming questionnaire: A high-lucidity group and a low-lucidity group. The researchers then used structural magnetic resonance imaging (MRI) and functional MRI (fMRI) to assess the neural mechanisms implicated in lucidity. All participants performed both a thought-monitoring task and a non-monitoring task while inside the MRI scanner. During both tasks, participants viewed an analog scale displayed on an overhead screen. In the thought monitoring task, participants were asked to indicate the degree to which they felt their thoughts were externally or internally focused by manipulating a curser on an analogue scale. In the non-monitoring task, participants were simply asked to align the curser to a circle that appeared on the screen.
Filevich et al (2015) found that the high-lucidity group showed greater volumes of grey matter in areas BA9/10 in the prefrontal cortex, and heightened blood-oxygen-level-dependent (BOLD) activity when undergoing the fMRI tests. Areas BA9/10 are known to be involved in metacognitive processes, including involvement in working memory tasks, interpreting abstract information, construing others’ mental states and multitasking. Of particular interest to the study of lucid dreaming, BA9/10 has also been shown to facilitate self-observation and it has been postulated to play a role in shifting between states of consciousness that involve internally- vs. externally-directed cognitive processes.
Filevich et al. (2015) also noted that the high-lucidity group showed increased grey matter within the left hippocampus. Because the hippocampus is known to play a role in one’s ability to recall dreams, the authors suggest that the hippocampus may be implicated in dream lucidity. That is, perhaps a greater hippocampal volume accounts for one’s ability to know with certainty that they are indeed dreaming.
As this study appears to be the first of it’s kind to assess lucidity and metacognitive ability through evaluating neural mechanisms, future research will help validate and expand upon the findings described here.
Filevich, E., Dresler, M., Brick, T. R., & Kühn, S. (2015). Metacognitive mechanisms underlying lucid dreaming. The Journal of Neuroscience, 35(3), 1082-1088. doi:10.1523/JNEUROSCI.3342-14.2015