Evolution of the E-WINDMIL:
Eyetracking Word Identification in Noise UnDer Memory Increased Load
2015: Hadar et. al. (2016) adapted the Visual world paradigm (Tanenhaus et al., 1995) to Hebrew and Validated it,
2016: Hadar et. al. (2016) examined the extent to which working memory load affects the timeline for the processing of a single spoken word by adding a working memory preload on younger adults. In the beginning of each trial, either one spoken digit (low load) or four spoken digits (high load) were presented. Participants were asked to retain the digit(s) while performing the spoken word recognition task. Once they had indicated their recognition of the spoken word (by touching the correct pictogram), they were asked to verbally recall the digit(s). 2 levels of working memory pre-load: high (4 digits) vs. low load (1 digit).
Example of the experimental display in Hebrew.
The target word, “/aʁ. nav/” (bunny), is represented in the bottom left corner. The phonological competitor /”aʁ.gaz/” (box), is represented in the upper right corner “siʁa” and “tiʁas” (boat and corn, respectively) are unrelated fillers.
Validity & Performance in Younger Adults
2019: Nitsan et. al. (2019) conducted a Secondary validation of Hebrew VWP with an additional ADVERSE NOISE condition on younger adults
Findings: We revealed individual differences in working memory capacity effect the time course of spoken word processing under a 4 digit preload in younger adults. 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.
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 emphasise the importance of considering differences in cognitive capacity, even when testing normal hearing young adults.
Reliability & Performance of Older Adults
As researchers increasingly apply the VWP in clinical settings to study speech processing in aging, we were asked whether this paradigm is reliable like the common VWP (Farris-Trimble and McMurray, 2013) across the lifespan. In response, we investigated the test-retest reliability of the E-WINDMIL in both younger and older adults.
Participants completed the task twice following a two-week interval. To prevent learning of paradigm stimuli, 2 image sets and 4 test versions were created from the original studies. As such, no participant viewed images nor heard target-object instructions from the first test session in the second test session.
Test Versions were not only counterbalanced among participants but between test sessions. For example, if a participant viewed image set 1 and began with the high memory load condition (4 digits to remember for later recall) than in test session (after 2 weeks time) they would view image set 2 and begin with the low load (single digit) condition.
With reliability tested, we are expanding out investigation into how individual working memory capacity effects spoken word processing in both younger and older adults.