TY - JOUR A1 - Nuthmann, Antje A1 - Vitu, Francoise A1 - Engbert, Ralf A1 - Kliegl, Reinhold T1 - No Evidence for a Saccadic Range Effect for Visually Guided and Memory-Guided Saccades in Simple Saccade-Targeting Tasks JF - PLoS one N2 - Saccades to single targets in peripheral vision are typically characterized by an undershoot bias. Putting this bias to a test, Kapoula [1] used a paradigm in which observers were presented with two different sets of target eccentricities that partially overlapped each other. Her data were suggestive of a saccadic range effect (SRE): There was a tendency for saccades to overshoot close targets and undershoot far targets in a block, suggesting that there was a response bias towards the center of eccentricities in a given block. Our Experiment 1 was a close replication of the original study by Kapoula [1]. In addition, we tested whether the SRE is sensitive to top-down requirements associated with the task, and we also varied the target presentation duration. In Experiments 1 and 2, we expected to replicate the SRE for a visual discrimination task. The simple visual saccade-targeting task in Experiment 3, entailing minimal top-down influence, was expected to elicit a weaker SRE. Voluntary saccades to remembered target locations in Experiment 3 were expected to elicit the strongest SRE. Contrary to these predictions, we did not observe a SRE in any of the tasks. Our findings complement the results reported by Gillen et al. [2] who failed to find the effect in a saccade-targeting task with a very brief target presentation. Together, these results suggest that unlike arm movements, saccadic eye movements are not biased towards making saccades of a constant, optimal amplitude for the task. Y1 - 2016 U6 - https://doi.org/10.1371/journal.pone.0162449 SN - 1932-6203 VL - 11 SP - 9935 EP - 9943 PB - PLoS CY - San Fransisco ER - TY - GEN A1 - Nuthmann, Antje A1 - Vitu, Françoise A1 - Engbert, Ralf A1 - Kliegl, Reinhold T1 - No evidence for a saccadic range effect for visually guided and memory-guided saccades in simple saccade-targeting tasks T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Saccades to single targets in peripheral vision are typically characterized by an undershoot bias. Putting this bias to a test, Kapoula [1] used a paradigm in which observers were presented with two different sets of target eccentricities that partially overlapped each other. Her data were suggestive of a saccadic range effect (SRE): There was a tendency for saccades to overshoot close targets and undershoot far targets in a block, suggesting that there was a response bias towards the center of eccentricities in a given block. Our Experiment 1 was a close replication of the original study by Kapoula [1]. In addition, we tested whether the SRE is sensitive to top-down requirements associated with the task, and we also varied the target presentation duration. In Experiments 1 and 2, we expected to replicate the SRE for a visual discrimination task. The simple visual saccade-targeting task in Experiment 3, entailing minimal top-down influence, was expected to elicit a weaker SRE. Voluntary saccades to remembered target locations in Experiment 3 were expected to elicit the strongest SRE. Contrary to these predictions, we did not observe a SRE in any of the tasks. Our findings complement the results reported by Gillen et al. [2] who failed to find the effect in a saccade-targeting task with a very brief target presentation. Together, these results suggest that unlike arm movements, saccadic eye movements are not biased towards making saccades of a constant, optimal amplitude for the task. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 506 KW - eye-movement control KW - scleral search coils KW - Z-reader model KW - psychophysics toolbox KW - oculomotor control KW - video-oculography KW - accuracy KW - microsaccades KW - eccentricity KW - tracking Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-411639 SN - 1866-8364 IS - 506 ER - TY - JOUR A1 - Schad, Daniel A1 - Nuthmann, Antje A1 - Engbert, Ralf T1 - Your mind wanders weakly, your mind wanders deeply - objective measures reveal mindless reading at different levels JF - Cognition : international journal of cognitive science N2 - When the mind wanders, attention turns away from the external environment and cognitive processing is decoupled from perceptual information. Mind wandering is usually treated as a dichotomy (dichotomy-hypothesis), and is often measured using self-reports. Here, we propose the levels of inattention hypothesis, which postulates attentional decoupling to graded degrees at different hierarchical levels of cognitive processing. To measure graded levels of attentional decoupling during reading we introduce the sustained attention to stimulus task (SAST), which is based on psychophysics of error detection. Under experimental conditions likely to induce mind wandering, we found that subjects were less likely to notice errors that required high-level processing for their detection as opposed to errors that only required low-level processing. Eye tracking revealed that before errors were overlooked influences of high- and low-level linguistic variables on eye fixations were reduced in a graded fashion, indicating episodes of mindless reading at weak and deep levels. Individual fixation durations predicted overlooking of lexical errors 5 s before they occurred. Our findings support the levels of inattention hypothesis and suggest that different levels of mindless reading can be measured behaviorally in the SAST. Using eye tracking to detect mind wandering online represents a promising approach for the development of new techniques to study mind wandering and to ameliorate its negative consequences. KW - Mind wandering KW - Reading KW - Eye movements KW - Signal detection theory KW - Levels of processing KW - Sustained attention Y1 - 2012 U6 - https://doi.org/10.1016/j.cognition.2012.07.004 SN - 0010-0277 VL - 125 IS - 2 SP - 179 EP - 194 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Nuthmann, Antje A1 - Smith, Tim J. A1 - Engbert, Ralf A1 - Henderson, John M. T1 - CRISP: a computational model of fixation duration in scene viewing N2 - Eye-movement control during scene viewing can be represented as a series of individual decisions about where and when to move the eyes. While substantial behavioral and computational research has been devoted to investigating the placement of fixations in scenes, relatively little is known about the mechanisms that control fixation durations. Here, we propose a computational model (CRISP) that accounts for saccade timing and programming and thus for variations in fixation durations in scene viewing. First, timing signals are modeled as continuous-time random walks. Second, difficulties at the level of visual and cognitive processing can inhibit and thus modulate saccade timing. Inhibition generates moment-by-moment changes in the random walk's transition rate and processing-related saccade cancellation. Third, saccade programming is completed in 2 stages: an initial, labile stage that is subject to cancellation and a subsequent, nonlabile stage. Several simulation studies tested the model's adequacy and generality. An initial simulation study explored the role of cognitive factors in scene viewing by examining how fixation durations differed under different viewing task instructions. Additional simulations investigated the degree to which fixation durations were under direct moment-to-moment control of the current visual scene. The present work further supports the conclusion that fixation durations, to a certain degree, reflect perceptual and cognitive activity in scene viewing. Computational model simulations contribute to an understanding of the underlying processes of gaze control. Y1 - 2010 UR - http://psycnet.apa.org/journals/rev/117/2/382/ ER - TY - JOUR A1 - Schad, Daniel A1 - Nuthmann, Antje A1 - Engbert, Ralf T1 - Eye movements during reading of randomly shuffled texts N2 - In research on eye-movement control during reading, the importance of cognitive processes related to language comprehension relative to visuomotor aspects of saccade generation is the topic of an ongoing debate. Here we investigate various eye-movement measures during reading of randomly shuffled meaningless text as compared to normal meaningful text. To ensure processing of the material, readers were occasionally probed for words occurring in normal or shuffled text. For reading of shuffled text we observed longer fixation times, less word skippings, and more refixations than in normal reading. Shuffled-text reading further differed from normal reading in that low-frequency words were not overall fixated longer than high-frequency words. However, the frequency effect was present on long words, but was reversed for short words. Also, consistent with our prior research we found distinct experimental effects of spatially distributed processing over several words at a time, indicating how lexical word processing affected eye movements. Based on analyses of statistical linear mixed-effect models we argue that the results are compatible with the hypothesis that the perceptual span is more strongly modulated by foveal load in the shuffled reading task than in normal reading. Results are discussed in the context of computational models of reading. Y1 - 2010 UR - http://dx.doi.org/10.1016/j.visres.2010.08.005 SN - 0042-6989 ER - TY - GEN A1 - Kuperman, Victor A1 - Dambacher, Michael A1 - Nuthmann, Antje A1 - Kliegl, Reinhold T1 - The effect of word position on eye-movements in sentence and paragraph reading N2 - 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. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 235 KW - eye movements KW - word processing KW - sentence processing Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-56828 ER - TY - JOUR A1 - Yan, Ming A1 - Kliegl, Reinhold A1 - Richter, Eike M. A1 - Nuthmann, Antje A1 - Shu, Hua T1 - Flexible saccade-target selection in Chinese reading N2 - As Chinese is written without orthographical word boundaries (i.e., spaces), it is unclear whether saccade targets are selected on the basis of characters or words and whether saccades are aimed at the beginning or the centre of words. Here, we report an experiment where 30 Chinese readers read 150 sentences while their eye movements were monitored. They exhibited a strong tendency to fixate at the word centre in single-fixation cases and at the word beginning in multiple-fixation cases. Different from spaced alphabetic script, initial fixations falling at the end of words were no more likely to be followed by a refixation than initial fixations at word centre. Further, single fixations were shorter than first fixations in two-fixation cases, which is opposite to what is found in Roman script. We propose that Chinese readers dynamically select the beginning or centre of words as saccade targets depending on failure or success with segmentation of parafoveal word boundaries. Y1 - 2010 UR - http://www.informaworld.com/smpp/title~content=t716100704~db=all U6 - https://doi.org/10.1080/17470210903114858 SN - 1747-0218 ER - TY - JOUR A1 - Nuthmann, Antje A1 - Engbert, Ralf T1 - Mindless reading revisited : an analysis based on the SWIFT model of eye-movement control N2 - In this article, we revisit the mindless reading paradigm from the perspective of computational modeling. In the standard version of the paradigm, participants read sentences in both their normal version as well as the transformed (or mindless) version where each letter is replaced with a z. z-String scanning shares the oculomotor requirements with reading but none of the higher-level lexical and semantic processes. Here we use the z-string scanning task to validate the SWIFT model of saccade generation [Engbert, R., Nuthmann, A., Richter, E., & Kliegl, R. (2005). SWIFT: A dynamical model of saccade generation during reading. Psychological Review, 112(4), 777-813] as an example for an advanced theory of eye-movement control in reading. We test the central assumption of spatially distributed processing across an attentional gradient proposed by the SWIFT model. Key experimental results like prolonged average fixation durations in z-string scanning compared to normal reading and the existence of a string-length effect on fixation durations and probabilities were reproduced by the model, which lends support to the model's assumptions on visual processing. Moreover, simulation results for patterns of regressive saccades in z-string scanning confirm SWIFT's concept of activation field dynamics for the selection of saccade targets. Y1 - 2009 UR - http://www.sciencedirect.com/science/journal/00426989 U6 - https://doi.org/10.1016/j.visres.2008.10.022 SN - 0042-6989 ER - TY - JOUR A1 - Nuthmann, Antje A1 - Kliegl, Reinhold T1 - An examination of binocular reading fixations based on sentence corpus data N2 - Binocular eye movements of normal adult readers were examined as they read single sentences. Analyses of horizontal and vertical fixation disparities indicated that the most prevalent type of disparate fixation is crossed (i.e., the left eye is located further to the right than the right eye) while the left eye frequently fixates somewhat above the right eye. The Gaussian distribution of the binocular fixation point peaked 2.6 cm in front of the plane of text, reflecting the prevalence of horizontally crossed fixations. Fixation disparity accumulates during the course of successive saccades and fixations within a line of text, but only to an extent that does not compromise single binocular vision. In reading, the version and vergence system interact in a way that is qualitatively similar to what has been observed in simple nonreading tasks. Finally, results presented here render it unlikely that vergence movements in reading aim at realigning the eyes at a given saccade target word. Y1 - 2009 UR - http://www.journalofvision.org/content/by/year U6 - https://doi.org/10.1167/9.5.31 SN - 1534-7362 ER - TY - JOUR A1 - Nuthmann, Antje A1 - Kliegl, Reinhold T1 - Preferred viewing locations : a validation Y1 - 2009 SN - 0301-0066 ER -