What Is a “Blank” Mind? Testing the Meaning and Construct Validity of Mind-Blanking Reports to Thought Probes

Abstract

Four studies evaluated probed mind-blanking reports, an off-task conscious state ostensibly experienced as an absence of thought and subjective experience. We examined whether people make mind-blanking reports to indicate uncertainty about their preceding thoughts, rather than to communicate an experienced “blank;” we also assessed whether subjects used “blank” to refer to the absence of experience, or rather an unclear, diffuse form of experience. U.S.-based Prolific participants were randomly assigned to one of three conditions that differed in thought-probe response options, which included or did not include “I-don’t-know” and “mind-blanking” options in Study 1a, 1b, and 2 (Ns = 463–790). Within an online go/no-go task, we tested whether different response options yielded different rates of mind-blanking and I-don’t-know reports. That is, would mind-blanking rates be higher when an “I don’t know” response option was not available, suggesting that mind-blanking reports indicate uncertainty? Would rates of I-don’t-know reports be lower when the “mind-blanking” option was unavailable? Neither mind-blanking nor I-don’t-know report rates differed significantly between probe-type conditions. Subjects were also confident and quick in their mind-blanking reports, with confidence ratings and report latencies matching other off-task thought categories. Subjects don’t use mind-blanking reports to reflect uncertainty. Study 3 (N = 415) extended our construct-validity investigation to the phenomenology of mind-blanking by separating “mind-blanking” response options into “unclear or foggy thoughts” versus “complete absence of experience.” Unclear thoughts accounted for 3% of thought reports, versus 1% reflecting no experience, suggesting that “blanking” more often reflects diffuse than absent subjective states.