Differences in Working Memory Capacity Affect Online Spoken Word Recognition: Evidence From Eye Movements

Trends Hear. 2019 Jan-Dec:23:2331216519839624. doi: 10.1177/2331216519839624.


Individual differences in working memory capacity have been gaining recognition as playing an important role in speech comprehension, especially in noisy environments. Using the visual world eye-tracking paradigm, a recent study by Hadar and coworkers found that online spoken word recognition was slowed when listeners were required to retain in memory a list of four spoken digits (high load) compared with only one (low load). In the current study, we recognized that the influence of a digit preload might be greater for individuals who have a more limited memory span. We compared participants with higher and lower memory spans on the time course for spoken word recognition by testing eye-fixations on a named object, relative to fixations on an object whose name shared phonology with the named object. Results show that when a low load was imposed, differences in memory span had no effect on the time course of preferential fixations. However, with a high load, listeners with lower span were delayed by ∼550 ms in discriminating target from sound-sharing competitors, relative to higher span listeners. This follows an assumption that the interference effect of a memory preload is not a fixed value, but rather, its effect is greater for individuals with a smaller memory span. Interestingly, span differences affected the timeline for spoken word recognition in noise, but not offline accuracy. This highlights the significance of using eye-tracking as a measure for online speech processing. Results further emphasize the importance of considering differences in cognitive capacity, even when testing normal hearing young adults.

Keywords: eye-tracking; online processing; visual world paradigm; word recognition; working memory.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Eye Movements / physiology*
  • Female
  • Humans
  • Individuality
  • Male
  • Memory, Short-Term / physiology*
  • Noise
  • Speech
  • Speech Perception / physiology*
  • Young Adult