Processing contextual and lexical cues to focus: Evidence from eye movements in reading

Three eye movement experiments investigated the interaction between contextual and lexical focus cues during reading. Context was used to focus on either the indirect or direct object of a double object construction, which was followed by a remnant continuation that formed either a congruous or incongruous contrast with the contextually focused object. Experiment 1 demonstrated that remnants were more difficult to process when incongruous with the contextually focused constituent, indicating that context was effective in specifying focus. Experiments 2 and 3 investigated the interaction between context and lexical focus arising from the particle only which specifies focus on the subsequent adjacent element. When only preceded both objects (Experiment 2), the conflict between lexical and contextual focus cues disrupted processing of the remnant element and was resolved in favour of the contextually focused element. However, when only was placed between both objects (Experiment 3), cue-conflict disrupted processing earlier in the sentence but did not appear to be fully resolved during on-line sentence processing. These findings reveal that the interplay between contextual and lexical cues to focus is important for establishing focus structure during on-line sentence processing

Visual grouping in accordance with utterance planning facilitates speech production

Research on language production has focused on the process of utterance planning and involved studying the synchronization between visual gaze and the production of sentences that refer to objects in the immediate visual environment. However, it remains unclear how the visual grouping of these objects might influence this process. To shed light on this issue, the present research examined the effects of the visual grouping of objects in a visual display on utterance planning in two experiments. Participants produced utterances of the form "The snail and the necklace are above/below/on the left/right side of the toothbrush" for objects containing these referents (e.g., a snail, a necklace and a toothbrush). These objects were grouped using classic Gestalt principles of color similarity (Experiment 1) and common region (Experiment 2) so that the induced perceptual grouping was congruent or incongruent with the required phrasal organization. The results showed that speech onset latencies were shorter in congruent than incongruent conditions. The findings therefore reveal that the congruency between the visual grouping of referents and the required phrasal organization can influence speech production. Such findings suggest that, when language is produced in a visual context, speakers make use of both visual and linguistic cues to plan utterances

Filtered text reveals adult age differences in reading: Evidence from eye movements

Sensitivity to certain spatial frequencies declines with age and this may have profound effects on reading performance. However, the spatial frequency content of text actually used by older adults (aged 65+), and how this differs from that used by young adults (aged 18–30), remains to be determined. To investigate this issue, the eye movement behavior of young and older adult readers was assessed using a gaze-contingent moving-window paradigm in which text was shown normally within a region centered at the point of gaze, whereas text outside this region was filtered to contain only low, medium, or high spatial frequencies. For young adults, reading times were affected by spatial frequency content when windows of normal text extended up to nine characters wide. Within this processing region, the reading performance of young adults was affected little when text outside the window contained either only high or medium spatial frequencies, but was disrupted substantially when text contained only low spatial frequencies. By contrast, the reading performance of older adults was affected by spatial frequency content when windows extended up to 18 characters wide. Moreover, within this extended processing region, reading performance was disrupted when text contained any one band of spatial frequencies, but was disrupted most of all when text contained only high spatial frequencies. These findings indicate that older adults are sensitive to the spatial frequency content of text from a much wider region than young adults, and rely much more than young adults on coarse-scale components of text when reading

The effects of interword spacing on the eye movements of young and older readers

Recent evidence indicates that older adults (aged 65+) are more disrupted by removing interword spaces than young adults (aged 18-30). However, it is not known whether older readers also show greater sensitivity to the more subtle changes to this spacing that frequently occur during normal reading. In the present study the eye movements of young and older adults were examined while reading texts for which interword spacing was normal, condensed to half its normal size, or expanded to 1.5 times its normal size. Although these changes in interword spacing affected eye movement behaviour, this influence did not differ between young and older adults. Furthermore, a word frequency manipulation showed that these changes did not affect word identification for either group. The results indicate that older adults can adapt their eye moment behaviour to accommodate subtle changes in the spatial layout of text equally effectively as young adults

Increased Vulnerability to Pattern-Related Visual Stress in Myalgic Encephalomyelitis

The objective of this study was to determine vulnerability to pattern-related visual stress in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). A total of 20 ME/CFS patients and 20 matched (age, gender) controls were recruited to the study. Pattern-related visual stress was determined using the Pattern Glare Test. Participants viewed three patterns, the spatial frequencies (SF) of which were 0.3 (low-SF), 2.3 (mid-SF), and 9.4 (high-SF) cycles per degree (c/deg). They reported the number of distortions they experienced when viewing each pattern. ME/CFS patients exhibited significantly higher pattern glare scores than controls for the mid-SF pattern. Mid-high SF differences were also significantly higher in patients than controls. These findings provide evidence of altered visual perception in ME/CFS. Pattern-related visual stress may represent an identifiable clinical feature of ME/CFS that will prove useful in its diagnosis. However, further research is required to establish if these symptoms reflect ME/CFS-related changes in the functioning of sensory neural pathways

What's left? An eye movement study of the influence of interword spaces to the left of fixation during reading

In English and other alphabetic systems read from left to right, the useful information acquired during each fixational pause is generally reported to extend 14-15 character spaces to the right of each fixation, but only 3-4 character spaces to the left, and certainly no farther than the beginning of the fixated word. However, this leftward extent is remarkably small and seems inconsistent with the general bilateral symmetry of vision. Accordingly, in the present study we investigated the influence of a fundamental component of text to the left of fixation-interword spaces-using a well-established eyetracking paradigm in which invisible boundaries were set up along individual sentence displays that were then read. Each boundary corresponded to the leftmost edge of a word in a sentence, so that as the eyes crossed a boundary, interword spaces in the text to the left of that word were obscured (by inserting a letter x). The proximity of the obscured text during each fixational pause was maintained at one, two, three, or four interword spaces from the left boundary of each fixated word. Normal fixations, regressions, and progressive saccades were disrupted when the obscured text was up to three interword spaces (an average of over 12 character spaces) away from the fixated word, while four interword spaces away produced no disruption. These findings suggest that influential information from text is acquired during each fixational pause from much farther leftward than is generally realized and that this information contributes to normal reading performance. Implications of these findings for reading are discussed

Aging and the control of binocular fixations during reading

Older adults (65 + years) often have greater difficulty in reading than young adults (18-30 years). However, the extent to which this difficulty is attributable to impaired eye-movement control is uncertain. To address this issue, the alignment and location of the two eyes' fixations during reading were monitored for young and older adults. Older adults showed typical patterns of reading difficulty but the results revealed no age differences in the alignment or location of the two eyes' fixations. Thus, the difficulty older adults experience in reading is not related to oculomotor control, which appears to be preserved into older age

Reading with filtered fixations : adult age differences in the effectiveness of low-level properties of text within central vision

When reading, low-level visual properties of text are acquired from central vision during brief fixational pauses, but the effectiveness of these properties may differ in older age. To investigate, a filtering technique displayed the low, medium, or high spatial frequencies of text falling within central vision as young (18-28 years) and older (65+ years) adults read. Reading times for normal text did not differ across age groups, but striking differences in the effectiveness of spatial frequencies were observed. Consequently, even when young and older adults read equally well, the effectiveness of spatial frequencies in central vision differs markedly in older age

Ageing and the Misperception of Words: Evidence from Eye Movements during Reading.

Research with lexical neighbours (words that differ by a single letter while the number and order of letters is preserved) indicates that readers frequently misperceive a word as its higher frequency neighbour (HFN) even during normal reading (Slattery, 2009). But how this lexical influence on word identification changes across the adult lifespan is largely unknown, although slower lexical processing and reduced visual abilities in later adulthood may lead to an increased incidence of word misperception errors. In particular, older adults may be more likely than younger adults to misidentify a word as its HFN, especially when the HFN is congruent with prior sentence context, although this has not been investigated. Accordingly, to address this issue, young and older adults read sentences containing target words with and without an HFN, where the HFN was either congruent with prior sentence context or not. Consistent with previous findings for young adults, eye movements were disrupted more for words with than without an HFN, especially when the HFN was congruent with prior context. Crucially, however, there was no indication of an adult age difference in this word misperception effect. We discuss these findings in relation to the nature of misperception effects in older age

Spontaneous re-reading within sentences: Eye movement control and visual sampling

Three experiments examine the role of previously read text in sentence comprehension and the control of eye movements during spontaneous re-reading. Spontaneous re-reading begins with a regressive saccade and involves re-inspection of previously read text. All three experiments employed the gaze contingent change technique to modulate the availability of previously read text. In Experiment 1 previously read text was permanently masked either immediately to the left of the fixated word (beyond wordn) or more than one word to the left (beyond wordn-1). The results of Experiment 1 indicate that the availability of the word immediately to the left (wordn-1) is important for comprehension. Experiments 2 and 3 further explored the role of previously read text beyond wordn-1. In these studies text beyond wordn-1 was replaced, retaining only word length information, or word length and shape information. Following a regression back within a sentence, meaningful text either re-appeared or remained unavailable during re-reading. The experiments show that the visual format of text beyond wordn-1 (the parafoveal postview) is important for triggering regressions. The results also indicate that, as least for more complex sentences, the availability of meaningful text is important in driving eye movement control during re-reading