Word features in parafoveal vision influence eye movements during reading. The question of whether readers extract semantic information from parafoveal words was studied in 3 experiments by using a gaze-contingent display change technique. Subjects read German sentences containing 1 of several preview words that were replaced by a target word during the saccade to the preview (boundary paradigm). In the 1st experiment the preview word was semantically related or unrelated to the target. Fixation durations on the target were shorter for semantically related than unrelated previews, consistent with a semantic preview benefit. In the 2nd experiment, half the sentences were presented following the rules of German spelling (i.e., previews and targets were printed with an initial capital letter), and the other half were presented completely in lowercase. A semantic preview benefit was obtained under both conditions. In the 3rd experiment, we introduced 2 further preview conditions, an identical word and a pronounceable nonword, while also manipulating the text contrast. Whereas the contrast had negligible effects, fixation durations on the target were reliably different for all 4 types of preview. Semantic preview benefits were greater for pretarget fixations closer to the boundary (large preview space) and, although not as consistently, for long pretarget fixation durations (long preview time). The results constrain theoretical proposals about eye movement control in reading.
Eye movements during reading proverbs and regular sentences: the incoming word predictability effect
(2014)
Many studies have shown that previewing the next word n + 1 during reading leads to substantial processing benefit (e.g., shorter word viewing times) when this word is eventually fixated. However, evidence of such preprocessing in fixations on the preceding word n when in fact the information about the preview is acquired is far less consistent. A recent study suggested that such effects may be delayed into fixations on the next word n + 1 (Risse & Kliegl, 2012). To investigate the time course of parafoveal information-acquisition on the control of eye movements during reading, we conducted 2 gaze-contingent display-change experiments and orthogonally manipulated the processing difficulty (i.e., word frequency) of an n + 1 preview word and its validity relative to the target word. Preview difficulty did not affect fixation durations on the pretarget word n but on the target word n + 1. In fact, the delayed preview-difficulty effect was almost of the same size as the preview benefit associated with the n + 1 preview validity. Based on additional results from quantile-regression analyses on the time course of the 2 preview effects, we discuss consequences as to the integration of foveal and parafoveal information and potential implications for computational models of eye guidance in reading.
During reading information is acquired from word(s) beyond the word that is currently looked at. It is still an open question whether such parafoveal information can influence the current viewing of a word, and if so, whether such parafoveal-on-foveal effects are attributable to distributed processing or to mislocated fixations which occur when the eyes are directed at a parafoveal word but land on another word instead. In two display-change experiments, we orthogonally manipulated the preview and target difficulty of word n+2 to investigate the role of mislocated fixations on the previous word n+1. When the eyes left word n, an easy or difficult word n+2 preview was replaced by an easy or difficult n+2 target word. In Experiment 1, n+2 processing difficulty was manipulated by means of word frequency (i.e., easy high-frequency vs. difficult low-frequency word n+2). In Experiment 2, we varied the visual familiarity of word n+2 (i.e., easy lower-case vs. difficult alternating-case writing). Fixations on the short word n+1, which were likely to be mislocated, were nevertheless not influenced by the difficulty of the adjacent word n+2, the hypothesized target of the mislocated fixation. Instead word n+1 was influenced by the preview difficulty of word n+2, representing a delayed parafoveal-on-foveal effect. The results challenge the mislocated-fixation hypothesis as an explanation of parafoveal-on-foveal effects and provide new insight into the complex spatial and temporal effect structure of processing inside the perceptual span during reading.
Although eye movements during reading are modulated by cognitive processing demands, they also reflect visual sampling of the input, and possibly preparation of output for speech or the inner voice. By simultaneously recording eye movements and the voice during reading aloud, we obtained an output measure that constrains the length of time spent on cognitive processing. Here we investigate the dynamics of the eye-voice span (EVS), the distance between eye and voice. We show that the EVS is regulated immediately during fixation of a word by either increasing fixation duration or programming a regressive eye movement against the reading direction. EVS size at the beginning of a fixation was positively correlated with the likelihood of regressions and refixations. Regression probability was further increased if the EVS was still large at the end of a fixation: if adjustment of fixation duration did not sufficiently reduce the EVS during a fixation, then a regression rather than a refixation followed with high probability. We further show that the EVS can help understand cognitive influences on fixation duration during reading: in mixed model analyses, the EVS was a stronger predictor of fixation durations than either word frequency or word length. The EVS modulated the influence of several other predictors on single fixation durations (SFDs). For example, word-N frequency effects were larger with a large EVS, especially when word N-1 frequency was low. Finally, a comparison of SFDs during oral and silent reading showed that reading is governed by similar principles in both reading modes, although EVS maintenance and articulatory processing also cause some differences. In summary, the EVS is regulated by adjusting fixation duration and/or by programming a regressive eye movement when the EVS gets too large. Overall, the EVS appears to be directly related to updating of the working memory buffer during reading.
Although eye movements during reading are modulated by cognitive processing demands, they also reflect visual sampling of the input, and possibly preparation of output for speech or the inner voice. By simultaneously recording eye movements and the voice during reading aloud, we obtained an output measure that constrains the length of time spent on cognitive processing. Here we investigate the dynamics of the eye-voice span (EVS), the distance between eye and voice. We show that the EVS is regulated immediately during fixation of a word by either increasing fixation duration or programming a regressive eye movement against the reading direction. EVS size at the beginning of a fixation was positively correlated with the likelihood of regressions and refixations. Regression probability was further increased if the EVS was still large at the end of a fixation: if adjustment of fixation duration did not sufficiently reduce the EVS during a fixation, then a regression rather than a refixation followed with high probability. We further show that the EVS can help understand cognitive influences on fixation duration during reading: in mixed model analyses, the EVS was a stronger predictor of fixation durations than either word frequency or word length. The EVS modulated the influence of several other predictors on single fixation durations (SFDs). For example, word-N frequency effects were larger with a large EVS, especially when word N-1 frequency was low. Finally, a comparison of SFDs during oral and silent reading showed that reading is governed by similar principles in both reading modes, although EVS maintenance and articulatory processing also cause some differences. In summary, the EVS is regulated by adjusting fixation duration and/or by programming a regressive eye movement when the EVS gets too large. Overall, the EVS appears to be directly related to updating of the working memory buffer during reading.
Reading requires the orchestration of visual, attentional, language-related, and oculomotor processing constraints. This study replicates previous effects of frequency, predictability, and length of fixated words on fixation durations in natural reading and demonstrates new effects of these variables related to previous and next words. Results are based on fixation durations recorded from 222 persons, each reading 144 sentences. Such evidence for distributed processing of words across fixation durations challenges psycholinguistic immediacy-of-processing and eye-mind assumptions. Most of the time the mind processes several words in parallel at different perceptual and cognitive levels. Eye movements can help to unravel these processes.
Eye movements in reading are sensitive to foveal and parafoveal word features. Whereas the influence of orthographic or phonological parafoveal information on gaze control is undisputed, there has been no reliable evidence for early parafoveal extraction of semantic information in alphabetic script. Using a novel combination of the gaze-contingent fast-priming and boundary paradigms, we demonstrate semantic preview benefit when a semantically related parafoveal word was available during the initial 125 ms of a fixation on the pre-target word (Experiments 1 and 2). When the target location was made more salient, significant parafoveal semantic priming occurred only at 80 ms (Experiment 3). Finally, with short primes only (20, 40, 60 ms) effects were not significant but numerically in the expected direction for 40 and 60 ms (Experiment 4). In all experiments, fixation durations on the target word increased with prime durations under all conditions. The evidence for extraction of semantic information from the parafoveal word favors an explanation in terms of parallel word processing in reading.
Using the gaze-contingent boundary paradigm with the boundary placed after word n, we manipulated preview of word n+2 for fixations on word n. There was no preview benefit for first-pass reading on word n+2, replicating the results of Rayner, Juhasz, and Brown (2007), but there was a preview benefit on the three-letter word n+1, that is, after the boundary, but before word n+2. Additionally, both word n+1 and word n+2 exhibited parafoveal-on-foveal effects on word n. Thus, during a fixation on word n and given a short word n+1, some information is extracted from word n+2, supporting the hypothesis of distributed processing in the perceptual span.
The present study explores the role of the word position-in-text in sentence and paragraph reading. Three eye-movement data sets based on the reading of Dutch and German unrelated sentences reveal a sizeable, replicable increase in reading times over several words in the beginning and the end of sentences. The data from the paragraphbased English-language Dundee corpus replicate the pattern and also indicate that the increase in inspection times is driven by the visual boundaries of the text organized in lines, rather than by syntactic sentence boundaries. We argue that this effect is independent of several established lexical, contextual and oculomotor predictors of eye-movement behavior. We also provide evidence that the effect of word position-intext has two independent components: a start-up effect arguably caused by a strategic oculomotor program of saccade planning over the line of text, and a wrap-up effect originating in cognitive processes of comprehension and semantic integration.