An investigation of parafoveal masks with the incremental boundary paradigm.

Florian Hutzler,Sarah Schuster,Stefan Hawelka,Christina Marx,Joshua Snell

doi:10.1371/journal.pone.0203013

Abstract

Most of what we know about parafoveal preprocessing during reading is based on the boundary paradigm in combination with parafoveal masks as a presumably neutral baseline condition. Recent evidence questions the neutrality of the baseline condition by showing that parafoveal masks inflict preview costs. Using a novel, incremental boundary paradigm we studied the effect of parafoveal masks. Manipulating the salience of parafoveal previews, we found that increasing salience of the masks resulted in increasingly longer fixation times on target words, but also on pretarget words—suggesting preview costs. We conclude that the hidden preview costs of parafoveal masks in the classical boundary paradigm inflate the processing times for the baseline condition and hence lead to an overestimation of the preview benefit. Thus, the present study questions the validity of some of the conclusions drawn on the basis of the classical boundary paradigm.

Highlights

During natural reading, we process written words with great speed and fluency
Most of what we know about parafoveal preprocessing is based on evidence from eye movement studies
Incremental boundary paradigm design is inherently impossible, because of missing data

Summary

Introduction

We process written words with great speed and fluency. This efficient processing depends on the fact that we do process the word which we are currently fixating, and preprocess the upcoming, parafoveal word. Most of what we know about parafoveal preprocessing is based on evidence from eye movement studies. In most of these studies, parafoveal preprocessing is investigated by means of a gaze-contingent display change technique, that is, the boundary paradigm [2]. The boundary paradigm makes it possible to experimentally manipulate the characteristics of the preview of the upcoming, parafoveal word. When the reader’s eyes cross the boundary, the preview is replaced by the target word (see [3][4] on the question of binocular foveation and the boundary technique)

Objectives

Methods

Results

Discussion

Conclusion