Bidirectional examination of the interaction between time and numerosity corroborates that numerosity influences time estimation but not vice versa

Scand J Psychol. 2018 Jun;59(3):252-261. doi: 10.1111/sjop.12445. Epub 2018 Apr 14.


There has been great interest in the idea that time, number, and space share a common magnitude system. However, only a handful of studies examined bidirectional interaction between time and number and the results varied depending on the specifics of the methods and stimulus properties of each study. The present study investigated bidirectional interaction between time and number using estimation tasks. We used duration (Experiment 1) and numerosity (Experiment 2) estimation tasks to investigate the effect of numerosity-on-duration and duration-on-numerosity estimation. The results from the two experiments demonstrated that numerosity influences duration processing but not vice versa; that is, there was unidirectional interaction between numerosity and time. The duration of stimulus presentation was overestimated for stimuli larger in (task-irrelevant) numerosity. Possible mechanisms underlying the unidirectional interaction between time and number are discussed.

Keywords: Time; common magnitude system; estimation; interaction; magnitude; numerosity.

MeSH terms

  • Adult
  • Female
  • Humans
  • Male
  • Mathematical Concepts*
  • Time Factors
  • Time Perception*
  • Young Adult