TY - JOUR A1 - Thiel, Marco A1 - Romano, Maria Carmen A1 - Kurths, Jürgen A1 - Rolfs, Martin A1 - Kliegl, Reinhold T1 - Generating surrogates from recurrences N2 - In this paper, we present an approach to recover the dynamics from recurrences of a system and then generate (multivariate) twin surrogate (TS) trajectories. In contrast to other approaches, such as the linear-like surrogates, this technique produces surrogates which correspond to an independent copy of the underlying system, i.e. they induce a trajectory of the underlying system visiting the attractor in a different way. We show that these surrogates are well suited to test for complex synchronization, which makes it possible to systematically assess the reliability of synchronization analyses. We then apply the TS to study binocular fixational movements and find strong indications that the fixational movements of the left and right eye are phase synchronized. This result indicates that there might be only one centre in the brain that produces the fixational movements in both eyes or a close link between the two centres. Y1 - 2008 UR - http://rsta.royalsocietypublishing.org/ SN - 1364-503X ER - TY - JOUR A1 - Risse, Sarah A1 - Engbert, Ralf A1 - Kliegl, Reinhold T1 - Eye-movement control in reading : experimental and corpus-analysis challenges for a computational model Y1 - 2008 SN - 978-7-201-06107-8 ER - TY - JOUR A1 - Angele, Bernhard A1 - Slattery, Timothy J. A1 - Yang, Jinmian A1 - Kliegl, Reinhold A1 - Rayner, Keith T1 - Parafoveal processing in reading : manipulating n+1 and n+2 previews simultaneously N2 - The boundary paradigm (Rayner, 1975) with a novel preview manipulation was used to examine the extent of parafoveal processing of words to the right of fixation. Words n + 1 and n + 2 had either correct or incorrect previews prior to fixation (prior to crossing the boundary location). In addition, the manipulation utilized either a high or low frequency word in word n + 1 location on the assumption that it would be more likely that n + 2 preview effects could be obtained when word n + 1 was high frequency. The primary findings were that there was no evidence for a preview benefit for word n + 2 and no evidence for parafoveal-on-foveal effects when word n + 1 is at least four letters long. We discuss implications for models of eye-movement control in reading. Y1 - 2008 UR - http://www.informaworld.com/smpp/title~content=t713683696~db=all U6 - https://doi.org/10.1080/13506280802009704 SN - 1350-6285 ER - TY - JOUR A1 - Göthe, Katrin A1 - Oberauer, Klaus A1 - Kliegl, Reinhold T1 - Age differences in dual-task performance after practice N2 - This study investigated whether older adults could acquire the ability to perform 2 cognitive operations in parallel in a paradigm in which young adults had been shown to be able to do so (K. Oberauer & R. Kliegl, 2004). Twelve young and 12 older adults practiced a numerical and a visuospatial continuous memory updating task in single-task and dual-task conditions for 16 to 24 sessions. After practice, 9 young adults were able to process the 2 tasks without dual- task costs, but none of the older adults had reached the criterion of parallel processing. The results suggest a qualitative difference between young and older adults in how they approach dual-task situations. Y1 - 2008 UR - http://psycnet.apa.org/index.cfm?fa=browsePA.volumes&jcode=pag U6 - https://doi.org/10.1037/0882-7974.22.3.596 SN - 0882-7974 ER - TY - JOUR A1 - Kinder, Annette A1 - Rolfs, Martin A1 - Kliegl, Reinhold T1 - Sequence learning at optimal stimulus-response mapping : evidence from a serial reaction-time task N2 - We propose a new version of the serial reaction time (SRT) task in which participants merely looked at the target instead of responding manually. As response locations were identical to target locations, stimulus - response compatibility was maximal in this task. We demonstrated that saccadic response times decreased during training and increased again when a new sequence was presented. It is unlikely that this effect was caused by stimulus - response (S - R) learning because bonds between (visual) stimuli and (oculomotor) responses were already well established before the experiment started. Thus, the finding shows that the building of S - R bonds is not essential for learning in the SRT task. Y1 - 2008 UR - http://tandfprod.literatumonline.com/doi/full/10.1080/17470210701557555 U6 - https://doi.org/10.1080/17470210701557555 ER - TY - JOUR A1 - Kliegl, Reinhold T1 - Publication statistics show collaboration, not competition Y1 - 2008 ER - TY - JOUR A1 - Lindenberger, Ulman A1 - Brehmer, Y. A1 - Kliegl, Reinhold A1 - Baltes, Paul B. T1 - Benefits of graphic design expertise in old age : compensatory effects of a graphical lexicon? Y1 - 2008 SN - 978-0-521-87205-8 ER - TY - JOUR A1 - Laubrock, Jochen A1 - Engbert, Ralf A1 - Kliegl, Reinhold T1 - Fixational eye movements predict the perceived direction of ambiguous apparent motion N2 - Neuronal activity in area LIP is correlated with the perceived direction of ambiguous apparent motion (Z. M. Williams, J. C. Elfar, E. N. Eskandar, L. J. Toth, & J. A. Assad, 2003). Here we show that a similar correlation exists for small eye movements made during fixation. A moving dot grid with superimposed fixation point was presented through an aperture. In a motion discrimination task, unambiguous motion was compared with ambiguous motion obtained by shifting the grid by half of the dot distance. In three experiments we show that (a) microsaccadic inhibition, i.e., a drop in microsaccade frequency precedes reports of perceptual flips, (b) microsaccadic inhibition does not accompany simple response changes, and (c) the direction of microsaccades occurring before motion onset biases the subsequent perception of ambiguous motion. We conclude that microsaccades provide a signal on which perceptual judgments rely in the absence of objective disambiguating stimulus information. Y1 - 2008 UR - http://www.journalofvision.org/content/by/year U6 - https://doi.org/10.1167/8.14.13 SN - 1534-7362 ER - TY - JOUR A1 - Moshel, Shay A1 - Zivotofsky, Ari Z. A1 - Liang, Jin-Rong A1 - Engbert, Ralf A1 - Kurths, Jürgen A1 - Kliegl, Reinhold A1 - Havlin, Shlomo T1 - Persistence and phase synchronization properties of fixational eye movement N2 - When we fixate our gaze on a stable object, our eyes move continuously with extremely small involuntary and autonomic movements, that even we are unaware of during their occurrence. One of the roles of these fixational eye movements is to prevent the adaptation of the visual system to continuous illumination and inhibit fading of the image. These random, small movements are restricted at long time scales so as to keep the target at the centre of the field of view. In addition, the synchronisation properties between both eyes are related to binocular coordination in order to provide stereopsis. We investigated the roles of different time scale behaviours, especially how they are expressed in the different spatial directions (vertical versus horizontal). We also tested the synchronisation between both eyes. Results show different scaling behaviour between horizontal and vertical movements. When the small ballistic movements, i.e., microsaccades, are removed, the scaling behaviour in both axes becomes similar. Our findings suggest that microsaccades enhance the persistence at short time scales mostly in the horizontal component and much less in the vertical component. We also applied the phase synchronisation decay method to study the synchronisation between six combinations of binocular fixational eye movement components. We found that the vertical-vertical components of right and left eyes are significantly more synchronised than the horizontal-horizontal components. These differences may be due to the need for continuously moving the eyes in the horizontal plane in order to match the stereoscopic image for different viewing distances. Y1 - 2008 UR - 1960 = DOI: 10.1140/epjst/e2008-00762-3 SN - 1951-6355 ER - TY - JOUR A1 - Ong, James Kwan Yau A1 - Kliegl, Reinhold T1 - Conditional co-occurrence probability acts like frequency in predicting fixation durations Y1 - 2008 UR - http://www.jemr.org/ SN - 1995-8692 ER - TY - JOUR A1 - Baptista, Murilo da Silva A1 - Bohn, Christiane A1 - Kliegl, Reinhold A1 - Engbert, Ralf A1 - Kurths, Jürgen T1 - Reconstruction of eye movements during blinks Y1 - 2008 UR - http://chaos.aip.org/ U6 - https://doi.org/10.1063/1.2890843 SN - 1054-1500 ER - TY - JOUR A1 - Rolfs, Martin A1 - Laubrock, Jochen A1 - Kliegl, Reinhold T1 - Microsaccade-induced prolongation of saccadic latencies depends on microsaccade amplitude Y1 - 2008 UR - http://www.jemr.org/ SN - 1995-8692 ER - TY - GEN A1 - Ong, James Kwan Yau A1 - Kliegl, Reinhold T1 - Conditional co-occurrence probability acts like frequency in predicting fixation durations N2 - The predictability of an upcoming word has been found to be a useful predictor in eye movement research, but is expensive to collect and subjective in nature. It would be desirable to have other predictors that are easier to collect and objective in nature if these predictors were capable of capturing the information stored in predictability. This paper contributes to this discussion by testing a possible predictor: conditional co-occurrence probability. This measure is a simple statistical representation of the relatedness of the current word to its context, based only on word co-occurrence patterns in data taken from the Internet. In the regression analyses, conditional co-occurrence probability acts like lexical frequency in predicting fixation durations, and its addition does not greatly improve the model fits. We conclude that readers do not seem to use the information contained within conditional co-occurrence probability during reading for meaning, and that similar simple measures of semantic relatedness are unlikely to be able to replace predictability as a predictor for fixation durations. Keywords: Co-occurrence probability, Cloze predictability, frequency, eye movement, fixation duration. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - paper 232 KW - Co-occurrence probability KW - Cloze predictability KW - eye movement KW - frequency KW - fixation duration Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-56771 ER - TY - GEN A1 - Kliegl, Reinhold T1 - Publication Statistics Show Collaboration, Not Competition T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - paper 258 Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-57198 ER - TY - JOUR A1 - Fanselow, Gisbert A1 - Kliegl, Reinhold A1 - Schlesewsky, Matthias T1 - Syntactic variation in German wh-questions Y1 - 2008 ER - TY - GEN A1 - Angele, Bernhard A1 - Slattery, Timothy J. A1 - Yang, Jinmian A1 - Kliegl, Reinhold A1 - Rayner, Keith T1 - Parafoveal processing in reading: Manipulating n+1 and n+2 previews simultaneously N2 - The boundary paradigm (Rayner, 1975) with a novel preview manipulation was used to examine the extent of parafoveal processing of words to the right of fixation. Words n+1 and n+2 had either correct or incorrect previews prior to fixation (prior to crossing the boundary location). In addition, the manipulation utilized either a high or low frequency word in word n+1 location on the assumption that it would be more likely that n+2 preview effects could be obtained when word n+1 was high frequency. The primary findings were that there was no evidence for a preview benefit for word n+2 and no evidence for parafoveal-on-foveal effects when word n+1 is at least four letters long. We discuss implications for models of eye-movement control in reading. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - paper 251 Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-57128 ER - TY - JOUR A1 - Rolfs, Martin A1 - Kliegl, Reinhold A1 - Engbert, Ralf T1 - Toward a model of microsaccade generation : the case of microsaccadic inhibition Y1 - 2008 UR - http://www.journalofvision.org/content/by/year U6 - https://doi.org/10.1167/8.11.5 SN - 1534-7362 ER - TY - JOUR A1 - Boston, Marisa Ferrara A1 - Hale, John A1 - Kliegl, Reinhold A1 - Patil, Umesh A1 - Vasishth, Shravan T1 - Parsing costs as predictors of reading difficulty : an evaluation using the Potsdam Sentence Corpus Y1 - 2008 UR - http://www.jemr.org/ SN - 1995-8692 ER - TY - JOUR A1 - Boston, Marisa Ferrara A1 - Hale, John A1 - Kliegl, Reinhold A1 - Vasishth, Shravan T1 - Surprising parser actions and reading difficulty Y1 - 2008 ER - TY - GEN A1 - Boston, Marisa Ferrara A1 - Hale, John A1 - Kliegl, Reinhold A1 - Patil, Umesh A1 - Vasishth, Shravan T1 - Parsing costs as predictors of reading difficulty: An evaluation using the Potsdam Sentence Corpus N2 - The surprisal of a word on a probabilistic grammar constitutes a promising complexity metric for human sentence comprehension difficulty. Using two different grammar types, surprisal is shown to have an effect on fixation durations and regression probabilities in a sample of German readers’ eye movements, the Potsdam Sentence Corpus. A linear mixed-effects model was used to quantify the effect of surprisal while taking into account unigram and bigram frequency, word length, and empirically-derived word predictability; the so-called “early” and “late” measures of processing difficulty both showed an effect of surprisal. Surprisal is also shown to have a small but statistically non-significant effect on empirically-derived predictability itself. This work thus demonstrates the importance of including parsing costs as a predictor of comprehension difficulty in models of reading, and suggests that a simple identification of syntactic parsing costs with early measures and late measures with durations of post-syntactic events may be difficult to uphold. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - paper 253 Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-57139 ER -