Sara C. Sereno

Establishing a time-line of word recognition : Evidence from eye movements and event-related potentials

THE average duration of eye fixations in reading places constraints on the time for lexical processing. Data from event related potential (ERP) studies of word recognition can illuminate stages of processing within a single fixation on a word. In the present study, high and low frequency regular and exception words were used as targets in an eye movement reading experiment and a high-density electrode ERP lexical decision experiment. Effects of lexicality (word vs pseudoword vs consonant strings), word frequency (high vs low frequency) and word regularity (regular vs exception spelling-sound correspondence) were examined. Results suggest a very early time-course for these aspects of lexical processing within the context of a single eye fixation.

Eye movement control in reading: A comparison of two types of models

: Two classes of models have been proposed to account for eye movement control during reading. Proponents of the 1st class of model claim that the decision of when to move the eyes (reflected in fixation duration) is primarily influenced by the status of on-line language processing such as lexical access. Supporters of the 2nd class of model, however, maintain that (a) lower level oculomotor factors such as fixation location govern the decision of when to move the eyes and (b) lexical variables exert only a weak influence. In this study, fixation duration on low-and high-frequency target words was examined as a function of fixation location and the number of fixations on a target word. The data are inconsistent with an oculomotor model.

Measuring word recognition in reading: eye movements and event-related potentials

The investigation of visual word recognition has been a major accomplishment of cognitive science. Two on-line methodologies, eye movements and event-related potentials, stand out in the search for the holy grail - an absolute time measure of when, how and why we recognize visual words while reading. Although each technique has its own experimental limitations, we suggest, by means of review and comparison, that these two methodologies can be used in complementary ways to produce a better picture of the mental action we call reading.

Eye movements and on-line language comprehension processes

Abstract Eye movement records have been used profitably to study on-line comprehension processes in reading. We present some basic facts about eye movements during reading, emphasising issues concerning the use of eye movement data to infer cognitive processes that are involved in (1) word processing, (2) syntactic parsing, and (3) higher-order processes. We review research on each of these topics and present new data dealing with word processing and high-order processes. We conclude that the analysis of eye movement records provides a great deal of useful information about on-line processing and that eye movement recording is a good way to study many critical issues concerning language comprehension processes.

Early emotion word processing: Evidence from event-related potentials

Behavioral and electrophysiological responses were monitored to 80 controlled sets of emotionally positive, negative, and neutral words presented randomly in a lexical decision paradigm. Half of the words were low frequency and half were high frequency. Behavioral results showed significant effects of frequency and emotion as well as an interaction. Prior research has demonstrated sensitivity to lexical processing in the N1 component of the event-related brain potential (ERP). In this study, the N1 (135-180 ms) showed a significant emotion by frequency interaction. The P1 window (80-120 ms) preceding the N1 as well as post-N1 time windows, including the Early Posterior Negativity (200-300 ms) and P300 (300-450 ms), were examined. The ERP data suggest an early identification of the emotional tone of words leading to differential processing. Specifically, high frequency negative words seem to attract additional cognitive resources. The overall pattern of results is consistent with a time line of word recognition in which semantic analysis, including the evaluation of emotional quality, occurs at an early, lexical stage of processing.

Phonological Codes Are Automatically Activated During Reading: Evidence From an Eye Movement Priming Paradigm

Subjects read sentences containing target words that were homophones (words with a single pronunciation but different spellings) while their eye movements were recorded A prime word was presented briefly at the onset of fixation on the target region The prime for a given target (e g, beach) was either identical to the target (beach), a phonologically similar word (the homophone beech), a visually similar nonhomophone (bench), or a dissimilar word (noise) Phonological priming effects were assessed by comparing fixation times on the target when it was preceded by the homophone versus the visually similar word Results suggest that phonological codes are automatically activated during eye fixations in reading

Eye movements and lexical ambiguity resolution: Investigating the subordinate bias effect

Recent debates on lexical ambiguity resolution have centered on the subordinate-bias effect, in which reading time is longer on a biased ambiguous word in a subordinate-biasing context than on a control word. The nature of the control word--namely, whether it matched the frequency of the ambiguous words overall word form or its contextually instantiated word meaning (a higher or lower frequency word, respectively)--was examined. In addition, contexts that were singularly supportive of the ambiguous words subordinate meaning were used. Eye movements were recorded as participants read contextually biasing passages that contained an ambiguous word target or a word-form or word-meaning control. A comparison of fixation times on the 2 control words revealed a significant effect of word frequency. Fixation times on the ambiguous word generally fell between those on the 2 controls and were significantly different than both. Results are discussed in relation to the reordered access model, in which both meaning frequency and prior context affect access procedures.

The Effect of Meaning Frequency on Processing Lexically Ambiguous Words: Evidence from Eye Fixations:

Subjects read sentences containing lexically ambiguous words while their eye movements were monitored Biased ambiguous words (those that have one highly dominant sense) were used in sentences containing a prior context that instantiated their subordinate sense Control words were matched in frequency both to the dominant and to the subordinate meaning of the ambiguous word (high- and low-frequency controls) Subjects fixated longer on both the ambiguous word and the low-frequency control than on the high-frequency control When the target was ambiguous, however, the duration of posttarget fixations was longer and the likelihood of making a regression to the target was greater than when the target was an unambiguous control The results are discussed in relation to current models of lexical ambiguity resolution

Parafoveal Magnification Visual Acuity Does Not Modulate the Perceptual Span in Reading

Models of eye guidance in reading rely on the concept of the perceptual span—the amount of information perceived during a single eye fixation, which is considered to be a consequence of visual and attentional constraints. To directly investigate attentional mechanisms underlying the perceptual span, we implemented a new reading paradigm—parafoveal magnification (PM)—that compensates for how visual acuity drops off as a function of retinal eccentricity. On each fixation and in real time, parafoveal text is magnified to equalize its perceptual impact with that of concurrent foveal text. Experiment 1 demonstrated that PM does not increase the amount of text that is processed, supporting an attentional-based account of eye movements in reading. Experiment 2 explored a contentious issue that differentiates competing models of eye movement control and showed that, even when parafoveal information is enlarged, visual attention in reading is allocated in a serial fashion from word to word.

Emotion Words Affect Eye Fixations during Reading.

Emotion words are generally characterized as possessing high arousal and extreme valence and have typically been investigated in paradigms in which they are presented and measured as single words. This study examined whether a words emotional qualities influenced the time spent viewing that word in the context of normal reading. Eye movements were monitored as participants read sentences containing an emotionally positive (e.g., lucky), negative (e.g., angry), or neutral (e.g., plain) word. Target word frequency (high or low) was additionally varied to help determine the temporal locus of emotion effects, with interactive results suggesting an early lexical locus of emotion processing. In general, measures of target fixation time demonstrated significant effects of emotion and frequency as well as an interaction. The interaction arose from differential effects with negative words that were dependent on word frequency. Fixation times on emotion words (positive or negative) were consistently faster than those on neutral words with one exception-high-frequency negative words were read no faster than their neutral counterparts. These effects emerged in the earliest eye movement measures, namely, first and single fixation duration, suggesting that emotionality, as defined by arousal and valence, modulates lexical processing. Possible mechanisms involved in processing emotion words are discussed, including automatic vigilance and desensitization, both of which imply a key role for word frequency. Finally, it is important that early lexical effects of emotion processing can be established within the ecologically valid context of fluent reading.