Elsewhere or Blanked? Ongoing mental states are regulated by pupil-linked arousal and attentional style in healthy ageing

Abstract

The reportability of spontaneous thinking relies significantly on attention and arousal. As these cognitive faculties change with age, we aimed at testing how spontaneous mental state reportability is influenced accordingly. Using experience sampling, 20 senior (65-75yrs) and 20 young participants (20-30yrs) were prompted to report mind-wandering (MW), mind-blanking (MB), or sensory-related (S) mental states at random times. Attention was assessed with the Attentional Style Questionnaire, and arousal with continuous monitoring of pupil diameter. First, we found more MW occurrences than MB or S across all participants. For young responders, we replicated that MW was more prevalent in easily-distracted participants. In seniors, though, MW was more prevalent in participants with a higher focused attentional style. In senior participants who reported being more easily distracted, MW was associated with lower arousal (pupil constriction) and MB with higher arousal (pupil dilation), reversing the pattern found for young adults and focused seniors. We propose that these effects may result from intentional MW, during which senior participants allocate attentional resources to mentally engage inwards, as opposed to younger participants who get more easily distracted by their own mental activity leading to unintentional MW. Together, our results highlight age-dependent mechanisms by which attentional style and pupil-linked arousal regulate the reportability of spontaneous mental states across age.