Whole-Brain Deactivations Precede Uninduced Mind-Blanking Reports

Area of Science:

• Neuroscience
• Cognitive Science
• Psychology

Background:

• Mind-blanking (MB) is the inability to report immediate mental content.
• Previous studies on MB's neural correlates often used induced states, showing frontal activation.
• The neural basis of spontaneous MB remains less understood.

Purpose of the Study:

• To investigate the neural correlates of spontaneous mind-blanking (MB) without induced states.
• To test the hypothesis that MB results from intentional mental content suppression.
• To differentiate neural activity during spontaneous MB from induced MB.

Main Methods:

• fMRI combined with experience-sampling in 31 participants.
• Univariate analysis of MB reports to identify brain region activations/deactivations.
• Bayesian region-of-interest analysis and contrast analysis comparing MB with content-oriented states.

Main Results:

• Spontaneous MB showed deactivations in occipital, frontal, parietal, and thalamic areas.
• No prefrontal activations were observed during spontaneous MB.
• Frontal deactivations were confirmed, contrasting with findings from induced MB studies.
• The left angular gyrus showed deactivations when comparing MB to content-oriented states.

Conclusions:

• Spontaneous MB is characterized by widespread brain deactivations, particularly in thalamocortical nodes.
• Intentional mental content suppression may not be the sole mechanism for MB.
• Study instructions significantly influence observed neural activation patterns in MB research.
• Findings provide mechanistic insights into the phenomenology of spontaneous MB and consciousness.