When we are awake, we assume that our thoughts are always racing with ideas. We keep our own dynamic mental stream, which is like a never-ending river stream.
A thought may lead to another, whether or not it is relevant to our actions, and it may ebb and flow between our inner and outside worlds. But how can the brain maintain such a thought-related state all the time? It absolutely cannot be done, according to a recent research published in the Proceedings of the National Academy of Sciences, since our brains must periodically “go offline,” which we perceive as mental gaps.
Re-analyzing a previously gathered dataset, researchers from the University of Liege, EPF Lausanne & University of Geneva asked healthy subjects to describe their mental state as it was just prior to receiving an auditory probe (beep) while lying still in the MRI scanner. The options were environmental perceptions, thoughts influenced by stimuli, ideas unaffected by stimuli, and mental lapses. Using this experience-sampling technique, good photos were gathered.
In contrast to the other states, mental blanking episodes were recorded much less frequently and recurred much less frequently over time, according to the researchers. The researchers also discovered, using machine learning, that during episodes of mind-numbing, our brains arranged so that all brain regions were in constant communication with one another.
The high amplitude of the fMRI global signal, a surrogate for low cortical arousal, further distinguished this ultra-connected brain pattern. To put it another way, when we describe mind blanking, our brains appear to be in a state that is comparable to deep sleep, except that we are awake.
Mind blanking is a relatively new mental state within the study of spontaneous cognition. It opens exciting avenues about the underlying biological mechanisms during waking life. It might be that the boundaries of sleep and wakefulness might not be that discrete as they appear to be after all”, says the principal investigator Dr Demertzi Athena, FNRS researcher at GIGA ULiege. “The continuously and rapidly changing brain activity requires robust analysis methods to confirm the specific signature of mind blanking”, continues Dr Van De Ville Dimitri.
The strict neurofunctional profile of mind blanking, according to the researchers, might explain why people are unable to report mental content because their brains are unable to discriminate signals in an instructional manner. This research demonstrates that instantaneous non-reportable mental experiences may occur during awake, establishing mind blanks as a relevant mental state throughout the current experience as we await clarification of the underlying processes.