An examination of relations between baseline pupil measures and cognitive abilities

Examining individual differences in pupil size and pupillary dynamics have revealed important insights into the nature of individual differences in cognitive abilities like working memory capacity, long-term memory, attention control, and fluid intelligence. These findings are often tied to the locus coeruleus-norepinephrine (LC-NE) system, as this system has a tight temporal correlation with pupil diameter. Some recent research has demonstrated positive correlations between resting pupil size and cognitive ability, specifically fluid intelligence. The present study attempted to replicate such relations. Across three studies, a large sample of participants (N = 845) completed batteries of cognitive ability measures and measures of resting pupil size and pupillary hippus (fluctuations in pupil diameter). The cognitive measures comprised tasks previously used to measure attention control, visual short-term memory capacity, fluid intelligence, working memory capacity, and visuospatial ability. At the factor level, cognitive ability and pupil size correlated near zero. We did observe some limited evidence for a negative correlation between resting pupillary hippus and cognitive ability. Given the null findings in the present data, we encourage further replication of relations between resting pupil measures and cognitive abilities before making any strong theoretical conclusions about such relations.

Automated summary

Examining individual differences in pupil size and pupillary dynamics has provided valuable insights into cognitive abilities such as working memory capacity, long-term memory, attention control, and fluid intelligence. The locus coeruleus-norepinephrine (LC-NE) system is often associated with these findings as it has a strong correlation with pupil diameter. Recent research has indicated a positive correlation between resting pupil size and cognitive ability, particularly fluid intelligence. However, the present study failed to replicate these findings, suggesting the need for further replication studies before drawing strong theoretical conclusions about the relationship between resting pupil measures and cognitive abilities.