Investigating eye movement acquisition and analysis technologies as a causal factor in differential prevalence of crossed and uncrossed fixation disparity during reading and dot scanning

Previous studies examining binocular coordination during reading have reported conflicting results in terms of the nature of disparity (e.g. Kliegl, Nuthmann, &amp; Engbert (Journal of Experimental Psychology General 135:12-35, 2006); Liversedge, White, Findlay, &amp; Rayner (Vision Research 46:2363-2374, 2006). One potential cause of this inconsistency is differences in acquisition devices and associated analysis technologies. We tested this by directly comparing binocular eye movement recordings made using SR Research EyeLink 1000 and the Fourward Technologies Inc. DPI binocular eye-tracking systems. Participants read sentences or scanned horizontal rows of dot strings; for each participant, half the data were recorded with the EyeLink, and the other half with the DPIs. The viewing conditions in both testing laboratories were set to be very similar. Monocular calibrations were used. The majority of fixations recorded using either system were aligned, although data from the EyeLink system showed greater disparity magnitudes. Critically, for unaligned fixations, the data from both systems showed a majority of uncrossed fixations. These results suggest that variability in previous reports of binocular fixation alignment is attributable to the specific viewing conditions associated with a particular experiment (variables such as luminance and viewing distance), rather than acquisition and analysis software and hardware.<br/

Comments on: “what is developmental dyslexia?” brain sci. 2018, 8, 26. the relationship between eye movements and reading difficulties

© 2018 by the authors. Licensee MDPI, Basel, Switzerland. We are writing in response to the review article: Stein. J. (2018). What is Developmental Dyslexia? Brain Sciences, 8, 26, doi:10.3390/brainsci8020026. We consider that the section entitled, “Eye Movement Control”, presents a misleading characterisation of current empirical and theoretical understanding. We outline five specific points relating to Stein’s views on eye movement control and developmental dyslexia with which we disagree and conclude that disruption to oculomotor behaviour occurs as a consequence of processing difficulty that individuals with dyslexia experience as they engage in reading

Predictability effects during reading in the absence of parafoveal preview.

The predictability of upcoming words facilitates spoken and written language comprehension (see Kuperberg & Jaeger, 2016 for a review). One difference between these language modalities is that readers’ routinely have access to upcoming words in parafoveal vision while listeners must wait for each word from a speaker. Despite readers’ potential glimpse into the future, it is not clear if and how this information aids prediction. The current study manipulated the predictability of target words and their location on a line of text. Targets were located in the middle of the line (preview available) or as the first word on a new line (preview unavailable). This represents an innovative method for manipulating parafoveal preview which utilizes return sweeps to deny access to parafoveal preview of target words without the use of invalid previews. The study is the first to demonstrate gaze duration word predictability effects in the absence of parafoveal preview

Online Processing Shows Advantages of Bimodal Listening-While-Reading for Vocabulary Learning: An Eye-Tracking Study

Children can learn words incidentally from stories. This kind of learning is enhanced when stories are presented both aurally and in written format, compared to just a written presentation. However, we do not know why this bimodal presentation is beneficial. This study explores two possible explanations: whether the bimodal advantage manifests online during story exposure, or later, at word retrieval. We collected eye-movement data from 34 8-to 9-year-old children exposed to two stories, one presented in written format (reading condition), and the second presented aurally and written at the same time (bimodal condition). Each story included six unfamiliar words (non-words) that were repeated three times, as well as definitions and clues to their meaning. Following exposure, the learning of the new words’ meanings was assessed. Results showed that, during story presentation, children spent less time fixating the new words in the bimodal condition, compared to the reading condition, indicating that the bimodal advantage occurs online. Learning was greater in the bimodal condition than the reading condition, which may reflect either an online bimodal advantage during story presentation or an advantage at retrieval. The results also suggest that the bimodal condition was more conducive to learning than the reading condition when children looked at the new words for a shorter amount of time. This is in line with an online advantage of the bimodal condition, as it suggests that less effort is required to learn words in this condition. These results support educational strategies that routinely present new vocabulary in two modalities simultaneousl

Return-sweep saccades during reading in adults and children

During reading, eye movement patterns differ between children and adults. Children make more fixations that are longer in duration and make shorter saccades. Return-sweeps are saccadic eye movements that move a reader’s fixation to a new line of text. Return-sweeps move fixation further than intra-line saccades and often undershoot their target. This necessitates a corrective saccade to bring fixation closer to the start of the line. There have been few empirical investigations of return-sweep saccades in adults, and even fewer in children. In the present study, we examined return-sweeps of 47 adults and 48 children who read identical multiline texts. We found that children launch their return-sweeps closer to the end of the line and target a position closer to the left margin. Therefore, children fixate more extreme positions on the screen when reading for comprehension. Furthermore, children required a corrective saccade following a return-sweep more often than adults. Analysis of the duration of the fixation preceding the corrective saccade indicated that children are as efficient as adults at responding to retinal feedback following a saccade. Rather than consider differences in adult’s and children’s return-sweep behaviour an artefact of oculomotor control, we believe that these differences represent adult’s ability to utilise parafoveal processing to encode text at extreme positions

Distraction by auditory novelty during reading: Evidence for disruption in saccade planning, but not saccade execution.

Novel or unexpected sounds that deviate from an otherwise repetitive sequence of the same sound cause behavioural distraction. Recent work has suggested that distraction also occurs during reading as fixation durations increased when a deviant sound was presented at the fixation onset of words. The present study tested the hypothesis that this increase in fixation durations occurs due to saccadic inhibition. This was done by manipulating the temporal onset of sounds relative to the fixation onset of words in the text. If novel sounds cause saccadic inhibition, they should be more distracting when presented during the second half of fixations when saccade programming usually takes place. Participants read single sentences and heard a 120 ms sound when they fixated five target words in the sentence. On most occasions (p= 0.9), the same sine wave tone was presented ("standard"), while on the remaining occasions (p= 0.1) a new sound was presented ("novel"). Critically, sounds were played either during the first half of the fixation (0 ms delay) or during the second half of the fixation (120 ms delay). Consistent with the saccadic inhibition hypothesis, novel sounds led to longer fixation durations in the 120 ms compared to the 0 ms delay condition. However, novel sounds did not generally influence the execution of the subsequent saccade. These results suggest that unexpected sounds have a rapid influence on saccade planning, but not saccade execution

Multimodality with Eye tracking and Haptics: A New Horizon for Serious Games?

The goal of this review is to illustrate the emerging use of multimodal virtual reality that can benefit learning-based games. The review begins with an introduction to multimodal virtual reality in serious games and we provide a brief discussion of why cognitive processes involved in learning and training are enhanced under immersive virtual environments. We initially outline studies that have used eye tracking and haptic feedback independently in serious games, and then review some innovative applications that have already combined eye tracking and haptic devices in order to provide applicable multimodal frameworks for learning-based games. Finally, some general conclusions are identified and clarified in order to advance current understanding in multimodal serious game production as well as exploring possible areas for new applications

What are the costs of degraded parafoveal previews during silent reading?

It has been suggested that the preview benefit effect is actually a combination of preview benefit and preview costs. Marx et al. (2015) proposed that visually degrading the parafoveal preview reduces the costs associated with traditional parafoveal letter masks used in the boundary paradigm (Rayner,1975), thus leading to a more neutral baseline. We report two experiments of skilled adults reading silently. In Experiment 1, we found no compelling evidence that degraded previews reduced processing costs associated with traditional letter masks. Moreover, participants were highly sensitive to detecting degraded display changes. Experiment 2 utilized the boundary detection paradigm (Slattery, Angele, & Rayner, 2011) to explore whether participants were capable of detecting actual letter changes or if they were responding purely to changes in degradation. Half of the participants were instructed to respond to any noticed display changes; the other half were instructed to respond only to changes in letter identities. Participants were highly sensitive to degraded changes. In fact, these changes were so apparent that they reduced the sensitivity to letter masks. In the context of the model proposed by Angele, Slattery, and Rayner (2016), we suggest that degraded previews interfere with the attentional stage, as evidenced by the general lack of foveal load effects. In summary, we found that increasingly degrading parafoveal letter masks does not reduce their processing costs in adults, but that both degraded valid and invalid previews introduce additional costs in terms of greater display change awareness