Deconstructing Frith and Snowling's homograph-reading task: Implications for autism spectrum disorders

Abstract

The poor performance of autistic individuals on a test of homograph reading is widely interpreted as evidence for a reduction in sensitivity to context termed “weak central coherence”. To better understand the cognitive processes involved in completing the homograph-reading task, we monitored the eye movements of nonautistic adults as they completed the task. Using single trial analysis, we determined that the time between fixating and producing the homograph (eye-to-voice span) increased significantly across the experiment and predicted accuracy of homograph pronunciation, suggesting that participants adapted their reading strategy to minimize pronunciation errors. Additionally, we found evidence for interference from previous trials involving the same homograph. This progressively reduced the initial advantage for dominant homograph pronunciations as the experiment progressed. Our results identify several additional factors that contribute to performance on the homograph reading task and may help to reconcile the findings of poor performance on the test with contradictory findings from other studies using different measures of context sensitivity in autism. The results also undermine some of the broader theoretical inferences that have been drawn from studies of autism using the homograph task. Finally, we suggest that this approach to task deconstruction might have wider applications in experimental psychology.

Keywords:

• Homographs
• Eye movements
• Speech production
• Autism
• Experimental design

Acknowledgments

This research was supported by Australian Research Council Discovery Project DP098466 and a Macquarie University Research Development Grant. We thank Joann Tang for assistance with data processing, Reinhold Kliegl for advice regarding statistical analyses, and Sachiko Kinoshita for comments on an earlier draft.