Auditory evoked potentials in lucid dreams: A dissertation summary
Are lucidly dreaming subjects able to discriminate between two different auditory stimuli using an oddball paradigm? How does the evoked potential (P300) in the EEG during this task look during lucidity, as compared to wakefulness and to non-lucid REM sleep? These are the central questions in Dr. Johannes Oliver Strelen’s dissertation, which is summarized in English language in this article. Six experienced lucid dreamers underwent polysomnographic recordings in the sleep laboratory for a total of 21 nights. Their task was to move their eyes from left to right, whenever they heard the target stimulus of an oddball paradigm, which was presented throughout the whole night. Three of the six subjects experienced a verified lucid dream and conducted the given task within it. The performance (correct responses) in the oddball task during lucid dreaming was worse than during wakefulness, but significantly better than what could be explained by chance. Thus, Strelen showed,that it is possible to react to simple auditory stimuli with a pre-defined eye movement, while dreaming lucidly, without waking up in between. Moreover, for two of his subjects, Strelen analyzed the auditory evoked potential (P300) of the EEG signal during the oddball paradigm. In one case, he found a clear, in the other case a questionable P300 peak. The morphology of the P300 EEG pattern for the correctly answered target stimuli during lucid dreaming was similar to the P300 EEG pattern during wakefulness, suggesting that information processing during lucid dreams is closer to wakefulness than to non-lucid REM sleep.