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As a contribution to a theoretical debate about the degree of high-level influences on saccade targeting during sentence reading, we investigated eye movements during the reading of structurally ambiguous Chinese character strings and examined whether parafoveal word segmentation could influence saccade-target selection. As expected, ambiguous strings took longer to process. More critically there were theoretically relevant interactions between ambiguity and launch site when first-fixation location and saccade amplitude served as dependent variables: Ambiguous strings in the parafovea triggered longer saccades and more rightward fixations for close launch sites than unambiguous ones; the reverse result was obtained for far launch sites. These crossover interactions indicate that parafoveal word segmentation influences saccade generation in Chinese and provide support of the hypothesis that high-level information can be involved in the decision about where to fixate next.
This article introduces childLex, an online database of German read by children. childLex is based on a corpus of children's books and comprises 10 million words that were syntactically annotated and lemmatized. childLex reports linguistic norms for lexical, superlexical, and sublexical variables in three different age groups: 6-8 (grades 1-2), 9-10 (grades 3-4), and 11-12 years (grades 5-6). Here, we describe how childLex was collected and analyzed. In addition, we provide information about the distributions of word frequency, word length, and orthographic neighborhood size, as well as their intercorrelations. Finally, we explain how childLex can be accessed using a Web interface.
Cognitive plasticity
(2002)
Cognitive research on the plasticity of fluid intelligence has demonstrated that older adults benefit markedly from guided practice in cognitive skills and problem-solving strategies. We examined to what degree older adults are capable by themselves of achieving similar practice gains, focusing on the fluid ability of figural relations. A sample of 72 healthy older adults was assigned randomly to three conditions: control, tutor-guided training, self-guided training. Training time and training materials were held constant for the two training conditions. Posttraining performances were analyzed using a transfer of training paradigm in terms of three indicators: correct responses, accuracy, and level of item difficulty. The training programs were effective and produced a significant but narrow band of within-ability transfer. However, there was no difference between the two training groups. Older adults were shown to be capable of producing gains by themselves that were comparable to those obtained following tutor-guided training in the nature of test-relevant cognitive skills.
During reading, our eyes perform complicated sequences of fixations on words. Stochastic models of eye movement control suggest that this seemingly erratic behaviour can be attributed to noise in the oculomotor system and random fluctuations in lexical processing. Here, we present a qualitative analysis of a recently published dynamical model [Engbert et al., 2002] and propose that deterministic nonlinear control accounts for much of the observed complexity of eye movement patterns during reading. Based on a symbolic coding technique we analyze robust statistical features of simulated fixation sequences
Concluding observations
(1999)
Word recognition in sentence reading is influenced by information from both preview and context. Recently, semantic preview effect (SPE) was observed being modulated by the constraint of context, indicating that context might accelerate the processing of semantically related preview words. Besides, SPE was found to depend on preview time, which suggests that SPE may change with different processing stages of preview words. Therefore, it raises the question of whether preview time-dependent SPE would be modulated by contextual constraint. In this study, we not only investigated the impact of contextual constraint on SPE in Chinese reading but also examined its dependency on preview time. The preview word and the target word were identical, semantically related or unrelated to the target word. The results showed a significant three-way interaction: The SPE depended on contextual constraint and preview time. In separate analyses for low and high contextual constraint of target words, the SPE significantly decreased with an increase in preview duration when the target word was of low constraint in the sentence. The effect was numerically in the same direction but weaker and statistically nonsignificant when the target word was highly constrained in the sentence. The results indicate that word processing in sentences is a dynamic process of integrating information from both preview (bottom-up) and context (top-down).
Brain-electric correlates of reading have traditionally been studied with word-by-word presentation, a condition that eliminates important aspects of the normal reading process and precludes direct comparisons between neural activity and oculomotor behavior. In the present study, we investigated effects of word predictability on eye movements (EM) and fixation-related brain potentials (FRPs) during natural sentence reading. Electroencephalogram (EEG) and EM (via video-based eye tracking) were recorded simultaneously while subjects read heterogeneous German sentences, moving their eyes freely over the text. FRPs were time-locked to first-pass reading fixations and analyzed according to the cloze probability of the currently fixated word. We replicated robust effects of word predictability on EMs and the N400 component in FRPs. The data were then used to model the relation among fixation duration, gaze duration, and N400 amplitude, and to trace the time course of EEG effects relative to effects in EM behavior. In an extended Methodological Discussion section, we review 4 technical and data-analytical problems that need to be addressed when FRPs are recorded in free-viewing situations (such as reading, visual search, or scene perception) and propose solutions. Results suggest that EEG recordings during normal vision are feasible and useful to consolidate findings from EEG and eye-tracking studies.
Fixational eye movements occur involuntarily during visual fixation of stationary scenes. The fastest components of these miniature eye movements are microsaccades, which can be observed about once per second. Recent studies demonstrated that microsaccades are linked to covert shifts of visual attention. Here, we generalized this finding in two ways. First, we used peripheral cues, rather than the centrally presented cues of earlier studies. Second, we spatially cued attention in vision and audition to visual and auditory targets. An analysis of microsaccade responses revealed an equivalent impact of visual and auditory cues on microsaccade-rate signature (i.e. an initial inhibition followed by an overshoot and a final return to the pre-cue baseline rate). With visual cues or visual targets, microsaccades were briefly aligned with cue direction and then opposite to cue direction during the overshoot epoch, probably as a result of an inhibition of an automatic saccade to the peripheral cue. With left auditory cues and auditory targets microsaccades oriented in cue direction. We argue that microsaccades can be used to study crossmodal integration of sensory information and to map the time course of saccade preparation during covert shifts of visual and auditory attention
Linguistic and psycholinguistic accounts based on the study of English may prove unreliable as guides to sentence processing in even closely related languages. The present study illustrates this claim in a test of sentence interpretation by German-, Italian-, and English-speaking adults. Subjects were presented with simple transitive sentences in which contrasts of (1) word order, (2) agreement, (3) animacy, and (4) stress were systematically varied. For each sentence, subjects were asked to state which of the two nouns was the actor. The results indicated that Americans relied overwhelming on word order, using a first-noun strategy in NVN and a second-noun strategy in VNN and NNV sentences. Germans relied on both agreement and animacy. Italians showed extreme reliance on agreement cues. In both German and Italian, stress played a role in terms of complex interactions with word order and agreement. The findings were interpreted in terms of the “competition model” of Bates and MacWhinney (in H. Winitz (Ed.), Annals of the New York Academy of Sciences Conference on Native and Foreign Language Acquisition. New York: New York Academy of Sciences, 1982) in which cue validity is considered to be the primary determinant of cue strength. According to this model, cues are said to be high in validity when they are also high in applicability and reliability.
Current advances in SWIFT
(2006)
Models of eye movement control are very useful for gaining insights into the intricate connections of different cognitive and oculomotor subsystems involved in reading. The SWIFT model (Engbert, Longtin, & Kliegl (2002). Vision Research, 42, 621 - 636) proposed a unified mechanism to account for all types of eye movement patterns that might be observed in reading behavior. The model is based on the notion of spatially distributed, or parallel, processing of words in a sentence. We present a refined version of SWIFT introducing a letter-based approach that proposes a processing gradient in the shape of a smooth function. We show that SWIFT extents its capabilities by accounting for distributions of landing positions.
Vier Forschungsansätze im Bereich der Altersintelligenz und des Altersgedächtnisses werden referiert: Untersuchungen (1) Uber unterschiedliche Altersverläufe intellektueller und kognitiver Prozesse, (2) über interindividuelle Variabilität und historischen Wandel, (3) über Plastizität und Reservekapazität und (4) über Leistungsgrenzen. Das Wesen der Altersintelligenz erschöpft sich nicht in einem Prozeß des Leistungsabfalls. Vielmehr treten sowohl Wachstum als auch Abbau und komplexe Wechselwirkungen zwischen beidem auf. Altersbedingter Abbau zeigt sich am ehesten an den Leistungsgrenzen der Grundmechanismen der Intelligenz. Wachstum kann in jenen Bereichen stattfinden, in denen Menschen Wissenssysteme weiterentwickeln und üben (Pragmatik der Intelligenz). Die Methode des Belastungstests (Testing-the-Limits oder Grenztesten) wird als eine Strategie vorgestellt, mit deren Hilfe Mechanismen positiver und negativer Veränderungen beim kognitiven Altern bestimmt werden können. Die Anwendung des kognitiven Belastungstests wird für die neuropsychologische Forschung, beispielsweise für Untersuchungen über die Altersdemenz, empfohlen.
The development of phonetic codes in memory of 141 pairs of normal and disabled readers from 7.8 to 16.8 years of age was tested with a task adapted from L. S. Mark, D. Shankweiler, I. Y. Liberman, and C. A. Fowler (Memory & Cognition, 1977, 5, 623–629) that measured false-positive errors in recognition memory for foil words which rhymed with words in the memory list versus foil words that did not rhyme. Our younger subjects replicated Mark et al., showing a larger difference between rhyming and nonrhyming false-positive errors for the normal readers. The older disabled readers' phonetic effect was comparable to that of the younger normal readers, suggesting a developmental lag in their use of phonetic coding in memory. Surprisingly, the normal readers' phonetic effect declined with age in the recognition task, but they maintained a significant advantage across age in the auditory WISC-R digit span recall test, and a test of phonological nonword decoding. The normals' decline with age in rhyming confusion may be due to an increase in the precision of their phonetic codes.
This longitudinal study investigated patterns of developmental problems across depression, aggression, and academic achievement during adolescence, using two measurement points two years apart (N = 1665; age T1: M = 13.14; female = 49.6%). Latent Profile Analyses and Latent Transition Analyses yielded four main findings: A three-type solution provided the best fit to the data: an asymptomatic type (i.e., low problem scores in all three domains), a depressed type (i.e., high scores in depression), an aggressive type (i.e., high scores in aggression). Profile types were invariant over the two data waves but differed between girls and boys, revealing gender specific patterns of comorbidity. Stabilities over time were high for the asymptomatic type and for types that represented problems in one domain, but moderate for comorbid types. Differences in demographic variables (i.e., age, socio-economic status) and individual characteristics (i.e., self-esteem, dysfunctional cognitions, cognitive capabilities) predicted profile type memberships and longitudinal transitions between types.
Many studies have shown that previewing the next word n + 1 during reading leads to substantial processing benefit (e.g., shorter word viewing times) when this word is eventually fixated. However, evidence of such preprocessing in fixations on the preceding word n when in fact the information about the preview is acquired is far less consistent. A recent study suggested that such effects may be delayed into fixations on the next word n + 1 (Risse & Kliegl, 2012). To investigate the time course of parafoveal information-acquisition on the control of eye movements during reading, we conducted 2 gaze-contingent display-change experiments and orthogonally manipulated the processing difficulty (i.e., word frequency) of an n + 1 preview word and its validity relative to the target word. Preview difficulty did not affect fixation durations on the pretarget word n but on the target word n + 1. In fact, the delayed preview-difficulty effect was almost of the same size as the preview benefit associated with the n + 1 preview validity. Based on additional results from quantile-regression analyses on the time course of the 2 preview effects, we discuss consequences as to the integration of foveal and parafoveal information and potential implications for computational models of eye guidance in reading.
Dissociating retention and access in working memory : an age-comparative study of mental arithmetic
(2001)
The lexical database dlexDB supplies in form of an online database frequency-based norms of numerous process-related word properties for psychological and linguistic research. These values include well known variables such as printed frequency of word form and lemma as documented also in CELEX (Baayen, Piepenbrock und Gulikers, 1995). In addition, we compute new values like frequencies based on syllables, and morphemes as well as frequencies of character chains, and multiple word combinations. The statistics are based on the Kernkorpus des Digitalen Wrterbuchs der deutschen Sprache (DWDS) with over 100 million running words. We illustrate the validity of these norms with new results about fixation durations in sentence reading.
Mit der lexikalischen Datenbank dlexDB stellen wir der psychologischen und linguistischen Forschung im World Wide Web online statistische Kennwerte für eine Vielzahl von verarbeitungsrelevanten Merkmalen von Wörtern zur Verfügung. Diese Kennwerte umfassen die durch CELEX (Baayen, Piepenbrock und Gulikers, 1995) bekannten Variablen der Häufigkeiten von Wortformen und Lemmata in Texten geschriebener Sprache. Darüber hinaus berechnen wir eine Reihe neuer Kennwerte wie die Häufigkeiten von Silben, Morphemen, Zeichenfolgen und Mehrwortverbindungen sowie Wortähnlichkeitsmaße. Die Datengrundlage bildet das Kernkorpus des Digitalen Wörterbuchs der deutschen Sprache (DWDS) mit über 100 Millionen laufenden Wörtern. Wir illustrieren die Validität dieser Kennwerte mit neuen Ergebnissen zu ihrem Einfluss auf Fixationsdauern beim Lesen von Sätzen.
Dyslexic and normal readers' eye movements were compared while tracking a moving fixation point and in reading. Contrary to previous reports, the dyslexic and normal readers did not differ in their number of saccades, percentage of regressions, or stability of fixations in the tracking task. Thus, defective oculomotor control was not associated with or a causal factor in dyslexia, and the dyslexics' abnormal eye movements in reading must be related to differences in higher cognitive processes. However, individual differences in oculmotor efficiency, independent of reading ability, were found within both the dyslexic and normal groups, and these differences were correlated in reading and tracking tasks.
Elderly adults (N = 116; average age = 73 years) were randomly assigned to one of four treatment groups varying in the amount of training and testing on fluid intelligence tests. They were compared before and after treatment on self-efficacy and utility beliefs for intelligence tests and everyday competence. Although both ability training and extended retest practice resulted in significant gains in objective test performance (Baltes, Kliegl, & Dittmann-Kohli, 1988), only ability training resulted in positive changes in self-efficacy. However, these changes were restricted to testrelated self-efficacy. Training had no impact on perceived utility or on everyday self-efficacy beliefs. Implications of the results are discussed with regard to interventions to increase intellectual self-efficacy in elderly persons.
Objective:
Therapist competence is considered essential for the success of psychotherapy. Feedback is an intervention which has the potential to improve therapist competence. The present study investigated whether competence feedback leads to an improvement of therapist competence and patient outcome.
Method:
Sixty-seven master-level clinical trainees were randomly assigned to either a competence feedback group (CFG) or a control group (CG). Patients with a diagnosis of major depression (N = 114) were randomly assigned to CFG or CG. Treatment included 20 individual sessions of cognitive behavioral therapy (CBT). In CFG, therapists received, parallel to the treatment, five competence feedbacks, based on videotaped therapy sessions. Independent raters assessed therapist competence with the Cognitive Therapy Scale (CTS) and provided the competence feedback. Patient outcome was evaluated with the Beck Depression Inventory-II (BDI-II) and therapeutic alliance (Helping Alliance Questionnaire [HAQ]) from both therapist's (HAQ-T) and patient's (HAQ-P) perspective were evaluated after each of the 20 sessions.
Results:
(a) Therapist competence (CTS) increased significantly more for CFG than CG. (b) Depression (BDI-II) decreased significantly across sessions for both groups, but without evidence for a group-differential benefit for the CFG. (c) Therapeutic alliance (HAQ-T/P) increased significantly across sessions for both groups from both perspectives, but without group differences. (d) There is a positive effect of BDI-II on CTS at the beginning and a negative effect of CTS on BDI-II at the end of therapy.
Conclusion:
Competence feedback improves therapists' independently rated competence, but there is no evidence that competence feedback in CBT leads to better outcome.
What is the public health significance of this article? This study suggests the substantial value of systematic competence feedback for improving therapist competence in the psychotherapy of depression. No significant effect of competence feedback on the reduction of reported depressive symptoms was found.
EMAN is an eye-movement analysis program that consists of four modules. The first module rescales eye positions to coordinates of the display. The second and third modules reduce data to a fixation format and identify areas of bad measurement by means of iterative passes over the data. In the fourth module iterative algorithms are employed for the identification of line numbers and for achieving congruence between fixations and display.
Human information processing depends critically on continuous predictions about upcoming events, but the temporal convergence of expectancy-based top-down and input-driven bottom-up streams is poorly understood. We show that, during reading, event-related potentials differ between exposure to highly predictable and unpredictable words no later than 90 ms after visual input. This result suggests an extremely rapid comparison of expected and incoming visual information and gives an upper temporal bound for theories of top-down and bottom-up interactions in object recognition.
During reading information is acquired from word(s) beyond the word that is currently looked at. It is still an open question whether such parafoveal information can influence the current viewing of a word, and if so, whether such parafoveal-on-foveal effects are attributable to distributed processing or to mislocated fixations which occur when the eyes are directed at a parafoveal word but land on another word instead. In two display-change experiments, we orthogonally manipulated the preview and target difficulty of word n+2 to investigate the role of mislocated fixations on the previous word n+1. When the eyes left word n, an easy or difficult word n+2 preview was replaced by an easy or difficult n+2 target word. In Experiment 1, n+2 processing difficulty was manipulated by means of word frequency (i.e., easy high-frequency vs. difficult low-frequency word n+2). In Experiment 2, we varied the visual familiarity of word n+2 (i.e., easy lower-case vs. difficult alternating-case writing). Fixations on the short word n+1, which were likely to be mislocated, were nevertheless not influenced by the difficulty of the adjacent word n+2, the hypothesized target of the mislocated fixation. Instead word n+1 was influenced by the preview difficulty of word n+2, representing a delayed parafoveal-on-foveal effect. The results challenge the mislocated-fixation hypothesis as an explanation of parafoveal-on-foveal effects and provide new insight into the complex spatial and temporal effect structure of processing inside the perceptual span during reading.
It is well established that fixation durations during reading vary with processing difficulty, but there are different views on how oculomotor control, visual perception, shifts of attention, and lexical (and higher cognitive) processing are coordinated. Evidence for a one-to-one translation of input delay into saccadic latency would provide a much needed constraint for current theoretical proposals. Here, we tested predictions of such a direct-control perspective using the stimulus-onset delay (SOD) paradigm. Words in sentences were initially masked and, on fixation, were individually unmasked with a delay (0-, 33-, 66-, 99-ms SODs). In Experiment 1, SODs were constant for all words in a sentence; in Experiment 2, SODs were manipulated on target words, while nontargets were unmasked without delay. In accordance with predictions of direct control, nonzero SODs entailed equivalent increases in fixation durations in both experiments. Yet, a population of short fixations pointed to rapid saccades as a consequence of low-level information at nonoptimal viewing positions rather than of lexical processing. Implications of these results for theoretical accounts of oculomotor control are discussed.
Linear mixed models (LMMs) provide a still underused methodological perspective on combining experimental and individual-differences research. Here we illustrate this approach with two-rectangle cueing in visual attention (Egly et al., 1994). We replicated previous experimental cue-validity effects relating to a spatial shift of attention within an object (spatial effect), to attention switch between objects (object effect), and to the attraction of attention toward the display centroid (attraction effect), also taking into account the design-inherent imbalance of valid and other trials. We simultaneously estimated variance/covariance components of subject-related random effects for these spatial, object, and attraction effects in addition to their mean reaction times (RTs). The spatial effect showed a strong positive correlation with mean RT and a strong negative correlation with the attraction effect. The analysis of individual differences suggests that slow subjects engage attention more strongly at the cued location than fast subjects. We compare this joint LMM analysis of experimental effects and associated subject-related variances and correlations with two frequently used alternative statistical procedures.
Linear mixed models (LMMs) provide a still underused methodological perspective on combining experimental and individual-differences research. Here we illustrate this approach with two-rectangle cueing in visual attention (Egly et al., 1994). We replicated previous experimental cue-validity effects relating to a spatial shift of attention within an object (spatial effect), to attention switch between objects (object effect), and to the attraction of attention toward the display centroid (attraction effect), also taking into account the design-inherent imbalance of valid and other trials. We simultaneously estimated variance/covariance components of subject-related random effects for these spatial, object, and attraction effects in addition to their mean reaction times (RTs). The spatial effect showed a strong positive correlation with mean RT and a strong negative correlation with the attraction effect. The analysis of individual differences suggests that slow subjects engage attention more strongly at the cued location than fast subjects. We compare this joint LMM analysis of experimental effects and associated subject-related variances and correlations with two frequently used alternative statistical procedures
The present study explored the age-related changes of eye movement control in reading-that is, where to send the eyes and when to move them. Different orthographies present readers with somewhat different problems to solve, and this might, in turn, be reflected in different patterns of development of reading skill. Participants of different developmental levels (Grade 3, N = 30; Grade 5, N = 27 and adults, N = 27) were instructed to read sentences for comprehension while their eye movements were recorded. Contrary to previous findings that have been well documented indicating early maturation of saccade generation in English, current results showed that saccade generation among Chinese readers was still under development at Grade 5, although immediate lexical processing was relatively well-established. The distinct age-related changes in eye movements are attributable to certain linguistic properties of Chinese including the lack of interword spaces and word boundary uncertainty. The present study offers an example of how human eye movement adapts to the orthographic environment.
The development of theories and computational models of reading requires an understanding of processing constraints, in particular of timelines related to word recognition and oculomotor control. Timelines of word recognition are usually determined with event-related potentials (ERPs) recorded under conditions of serial visual presentation (SVP) of words; timelines of oculomotor control are derived from parameters of eye movements (EMs) during natural reading. We describe two strategies to integrate these approaches. One is to collect ERPs and EMs in separate SVP and natural reading experiments for the same experimental material (but different subjects). The other strategy is to co-register EMs and ERPs during natural reading from the same subjects. Both strategies yield data that allow us to determine how lexical properties influence ERPs (e.g., the N400 component) and EMs (e.g., fixation durations) across neighboring words. We review our recent research on the effects of frequency and predictability of words on both EM and ERP measures with reference to current models of eye-movement control during reading. Results are in support of the proposition that lexical access is distributed across several fixations and across brain-electric potentials measured on neighboring words.
Eye movements during reading proverbs and regular sentences: the incoming word predictability effect
(2014)
It is generally accepted that low-level features (e.g., inter-word spaces) are responsible for saccade-target selection in eye-movement control during reading. In two experiments using Uighur script known for its rich suffixes, we demonstrate that, in addition to word length and launch site, the number of suffixes influences initial landing positions. We also demonstrate an influence of word frequency. These results are difficult to explain purely by low-level guidance of eye movements and indicate that due to properties specific to Uighur script low-level visual information and high-level information such as morphological structure of parafoveal words jointly influence saccade programming. (C) 2014 Elsevier B.V. All rights reserved.
Contents: I. Introduction II. Word Coding Processes A. Word Recognition B. Orthographic Coding C. Phonological Coding III. Eye Monitor and Reading Task IV. Group Differences V. Dimensions of Individual Differences A. Regressive Fixation Index and Word Recognition B. Regressive Fixation Index and IQ C. Regressive Fixation Index and Saccade Length D. Regressive Fixation Index and Relative Phonological Skill VI. Multiple Regression Models of Individual Differences A. Disabled Readers in the Aloud Condition B. Disabled Readers in the Silent Condition C. Normal Readers in Silent and Aloud Conditions VII. Conclusions
We measured Chinese dyslexic and control children's eye movements during rapid automatized naming (RAN) with alphanumeric (digits) and symbolic (dice surfaces) stimuli. Both types of stimuli required identical oral responses, controlling for effects associated with speech production. Results showed that naming dice was much slower than naming digits for both groups, but group differences in eye-movement measures and in the eye-voice span (i.e. the distance between the currently fixated item and the voiced item) were generally larger in digit-RAN than in dice-RAN. In addition, dyslexics were less efficient in parafoveal processing in these RAN tasks. Since the two RAN tasks required the same phonological output and on the assumption that naming dice is less practiced than naming digits in general, the results suggest that the translation of alphanumeric visual symbols into phonological codes is less efficient in dyslexic children. The dissociation of the print-to-sound conversion and phonological representation suggests that the degree of automaticity in translation from visual symbols to phonological codes in addition to phonological processing per se is also critical to understanding dyslexia.
We resolve a controversy about reading fixations before word-skipping saccades which were reported as longer or shorter than control fixations in earlier studies. Our statistics are based on resampling of matched sets of fixations before skipped and nonskipped words, drawn from a database of 121,321 single fixations contributed by 230 readers of the Potsdam sentence corpus. Matched fixations originated from single-fixation forward-reading patterns and were equated for their positions within words. Fixations before skipped words were shorter before short or high-frequency words and longer before long or low-frequency words in comparison with control fixations. Reasons for inconsistencies in past research and implications for computational models are discussed
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.
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.
Bei N = 101 Arbeitnehmern verschiedener Berufe wurden mit der Experience Sampling Method (ESM) eine Woche lang Daten zum Flow-Erleben, zu Glück/Zufriedenheit und zur Zielausrichtung laufender Aktivitäten erhoben (N = 4603 Messungen). Die Daten wurden mit GLMM-Analysen ausgewertet. Auch bei der jetzt vollständigen Erfassung aller Flow-Komponenten mit der FKS bestätigte sich das „Paradoxon der Arbeit“, wonach während der Arbeit höhere Flow-Werte, aber niedrigere Werte für Glück/Zufriedenheit auftreten als jeweils in der Freizeit. Während der Arbeit waren Aktivitäten häufiger auf die Erreichung von Zielen ausgerichtet als während der Freizeit. Die Zielausrichtung wirkte auf Flow vs. Glück/Zufriedenheit signifikant verschieden. Während der Arbeit hat die Zielausrichtung auf Flow einen stark positiven Effekt, auf Glück/Zufriedenheit jedoch nicht. Im Freizeitbereich war der Effekt von Zielausrichtung auf Glück/Zufriedenheit sogar negativ. Das „Paradoxon der Arbeit“ lässt sich partiell als Effekt der Zielausrichtung verstehen.
In alphabetic writing systems, saccade amplitude (a close correlate of reading speed) is independent of font size, presumably because an increase in the angular size of letters is compensated for by a decrease of visual acuity with eccentricity. We propose that this invariance may (also) be due to the presence of spaces between words, guiding the eyes across a large range of font sizes. Here, we test whether saccade amplitude is also invariant against manipulations of font size during reading Chinese, a character-based writing system without spaces as explicit word boundaries for saccade-target selection. In contrast to word-spaced alphabetic writing systems, saccade amplitude decreased significantly with increased font size, leading to an increase in the number of fixations at the beginning of words and in the number of refixations. These results are consistent with a model which assumes that word beginning (rather than word center) is the default saccade target if the length of the parafoveal word is not available.
Effects of frequency, predictability, and position of words on event-related potentials were assessed during word-by-word sentence reading in 48 subjects in an early and in a late time window corresponding to P200 and N400. Repeated measures multiple regression analyses revealed a P200 effect in the high-frequency range also the P200 was larger on words at the beginning and end of sentences than on words in the middle of sentences (i.e., a quadratic effect of word position). Predictability strongly affected the N400 component; the effect was stronger for low than for high- frequency words. The P200 frequency effect indicates that high-frequency words are lexically accessed very fast, independent of context information. Effects on the N400 suggest that predictability strongly moderates the late access especially of low-frequency words. Thus, contextual facilitation on the N400 appears to reflect both lexical and post- lexical stages of word recognition, questioning a strict classification into lexical and post-lexical processes.
Manipulations of presentation time have a long history in research on the development of memory, with a number of paradoxical results deriving from methodological shortcomings as well as from insufficient theoretical specifications. After a look at some of the problems in earlier research, a psychophysics approach to investigate episodic memory functions is presented in which criterion-referenced manipulation of presentation time is used to estimate the effects of experimental manipulations and the effects of individual differences. Criterion'referenced presentation time (CRPT), defined as the time required to score at an a priori specified level of accuracy, is interpreted as a preliminary indicator of internal processing time. CRPTs are shown to be valid predictors of traditional measures of memory accuracy. Moreover, an extension of this psychophysics approach yields estimates of complete condition-specific timeaccuracy functions and of function-specific processing times (plus other parameters) for individual subjects. It is argued that both from a cognitive and a developmental perspective it is often advantageous to trade experimental equivalence in presentation times for functional equivalence in accuracy of performance; this applies not only to episodic memory processes.
Earlier testing-the-limits research on age differences in cognitive plasticity of a memory skill was extended by 18 additional assessment and training sessions to explore whether older adults were able to catch up with additional practice and improved training conditions. The focus was on the method of loci, which requires mental imagination to encode and retrieve lists of words from memory in serial order. Of the original 37 subjects, 35 (16 young, ranging from 20 to 30 years of age, and 19 older adults, ranging from 66 to 80 years of age) participated in the follow-up study. Older adults showed sizable performance deficits when compared with young adults and tested for limits of reserve capacity. The negative age difference was substantial, resistant to extensive practice, and applied to all subjects studied. The primary origin for this negative age difference may be a loss in the production and use of mental imagination for operations of the mind.
Gedächtnistraining im Alter
(2000)
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 one centre only in the brain that produces the fixational movements in both eyes or a close link between two centres.
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.
How preview space/time translates into preview cost/benefit for fixation durations during reading
(2013)
Eye-movement control during reading depends on foveal and parafoveal information. If the parafoveal preview of the next word is suppressed, reading is less efficient. A linear mixed model (LMM) reanalysis of McDonald (2006) confirmed his observation that preview benefit may be limited to parafoveal words that have been selected as the saccade target. Going beyond the original analyses, in the same LMM, we examined how the preview effect (i.e., the difference in single-fixation duration, SFD, between random-letter and identical preview) depends on the gaze duration on the pretarget word and on the amplitude of the saccade moving the eye onto the target word. There were two key results: (a) The shorter the saccade amplitude (i.e., the larger preview space), the shorter a subsequent SFD with an identical preview; this association was not observed with a random-letter preview. (b) However, the longer the gaze duration on the pretarget word, the longer the subsequent SFD on the target, with the difference between random-letter string and identical previews increasing with preview time. A third patternincreasing cost of a random-letter string in the parafovea associated with shorter saccade amplitudeswas observed for target gaze durations. Thus, LMMs revealed that preview effects, which are typically summarized under preview benefit, are a complex mixture of preview cost and preview benefit and vary with preview space and preview time. The consequence for reading is that parafoveal preview may not only facilitate, but also interfere with lexical access.
We question the assumption of serial attention shifts and the assumption that saccade programs are initiated or canceled only after stage one of word identification. Evidence: (1) Fixation durations prior to skipped words are not consistently higher compared to those prior to nonskipped words. (2) Attentional modulation of microsaccade rate might occur after early visual processing. Saccades are probably triggered by attentional selection.
We question the assumption of serial attention shifts and the assumption that saccade programs are initiated or canceled only after stage one of word identification. Evidence: (1) Fixation durations prior to skipped words are not consistently higher compared to those prior to non-skipped words. (2) Attentional modulation of microsaccade rate might occur after early visual processing. Saccades are probably triggered by attentional selection
Factorial experiments in research on memory, language, and in other areas are often analyzed using analysis of variance (ANOVA). However, for effects with more than one numerator degrees of freedom, e.g., for experimental factors with more than two levels, the ANOVA omnibus F-test is not informative about the source of a main effect or interaction. Because researchers typically have specific hypotheses about which condition means differ from each other, a priori contrasts (i.e., comparisons planned before the sample means are known) between specific conditions or combinations of conditions are the appropriate way to represent such hypotheses in the statistical model. Many researchers have pointed out that contrasts should be "tested instead of, rather than as a supplement to, the ordinary 'omnibus' F test" (Hays, 1973, p. 601). In this tutorial, we explain the mathematics underlying different kinds of contrasts (i.e., treatment, sum, repeated, polynomial, custom, nested, interaction contrasts), discuss their properties, and demonstrate how they are applied in the R System for Statistical Computing (R Core Team, 2018). In this context, we explain the generalized inverse which is needed to compute the coefficients for contrasts that test hypotheses that are not covered by the default set of contrasts. A detailed understanding of contrast coding is crucial for successful and correct specification in linear models (including linear mixed models). Contrasts defined a priori yield far more useful confirmatory tests of experimental hypotheses than standard omnibus F-tests. Reproducible code is available from https://osf.io/7ukf6/.
I. Introduction A. Theoretical Framework and Selection of Tests B. Related Studies of Reading Disability Subtypes C. Overview of Specific Questions and Article Outline II. Selection criteria nd performance on standardized measures III. Group differences between disabled and normal readers A. Phonetic Memory B. Picture-Naming Speed and Automatic Responses to Print C. Phonological and Orthographic Skill D. Easy Regular and Exception Word Reading E. Difficult Regular and Exception Words IV. Individual diferences in reading disability A. Phonological Skill, Orthographic Skill, and the Regularity Effect B. Phonological Skill, Orthographic Skill, and Spelling Errors V. Eye movement reading style A. The "Plodder-Explorer" Dimension of Eye Movement Reading Style B. Eye Movements, Coding Skills, and Spelling Ratings C. Verbal Intelligence and the Plodder-Explorer Dimension D. Eye Movements in a Nonreading Task and the "Visual-Spatial" Subtype VI. Distribution and etiology of reading disabilities A. Distribution Issues B. Etiology of Reading Disabilities VII. Summary and new directions in research
Protanopie, deuteranopic and tritanopic neutral points were computed by determining the wavelength of light that produced the same quantal-catch ratio in the photopigments as that produced by a broad-band light of specified color temperature (range: 2 800—6 600 K). The Vos-Walraven primaries were used as photopigment absorption spectra that were screened by varying densities of ocular (0.5—2.5 at 400 nm) and macular (0.0—1.0 at 460 nm) pigmentation. The computations were carried out in 1 nm steps for the wavelength range of 380 to 720 nm. Most of the empirically determined mean, neutral-point loci in the literature were predicted from these computations to within 1—2nm when average ocular and macular pigment densities were used. The neutral-point range associated with the extreme values of the prereceptoral screening pigments was up to 25 nm for protanopes and deuteranopes and up to 13 nm for tritanopes.
There has been a substantial increase in the percentage for publications with co-authors located in departments from different countries in 12 major journals of psychology. The results are evidence for a remarkable internationalization of psychological research, starting in the mid 1970s and increasing in rate at the beginning of the 1990s. This growth occurs against a constant number of articles with authors from the same country; it is not due to a concomitant increase in the number of co-authors per article. Thus, international collaboration in psychology is obviously on the rise.
There has been a substantial increase in the percentage for publications with co-authors located in departments from different countries in 12 major journals of psychology. The results are evidence for a remarkable internationalization of psychological research, starting in the mid 1970s and increasing in rate at the beginning of the 1990s. This growth occurs against a constant number of articles with authors from the same country; it is not due to a concomitant increase in the number of co-authors per article. Thus, international collaboration in psychology is obviously on the rise.
There has been a substantial increase in the percentage for publications with co-authors located in departments from different countries in 12 major journals of psychology. The results are evidence for a remarkable internationalization of psychological research, starting in the mid 1970s and increasing in rate at the beginning of the 1990s. This growth occurs against a constant number of articles with authors from the same country; it is not due to a concomitant increase in the number of co-authors per article. Thus, international collaboration in psychology is obviously on the rise.
Kognitive Komplexität
(1996)
Kognitive Plastizität und altersbedingte Grenzen am Beispiel des Erwerbs einer Gedächtnistechnik
(1989)
Die Bedeutung kognitiver Entwicklungskapazität (Plastizität) und ihrer altersabhängigen Grenzen für Theorien kognitiven Alters wird thematisiert. Für kognitive Basisprozesse wird erwartet, daß die durch Training umgesetzte Entwicklungskapazität älterer Menschen zwar ausreicht, die Ausgangsleistung junger Erwachsener zu übertreffen, daß aber aufgrund altersbedingter Grenzen der Entwicklungskapazität nur sehr wenige ältere Erwachsene das Leistungsniveau trainierter junger Erwachsener erreichen werden. Am Beispiel eines Gedächtnistrainingsprogrammes zur Erhöhung der Merkfähigkeit für Wortlisten werden zwei Forschungsstrategien vorgestellt: (a) das Training von sehr leistungsfähigen älteren Erwachsenen und (b) Längsschnitt-Einzelfall-Studien. Die experimentellen Befunde bestätigten die theoretischen Erwartungen. Zwar waren die Leistungen der besten älteren Erwachsenen etwa doppelt so hoch wie die untrainierter junger Erwachsener, aber die durch das Training aufgedeckten Altersverluste konnten auch in bis zu 75 weiteren Übungsstunden nicht behoben werden.
Gedächtnishöchstleistungen sind auch im Alter möglich. Dies konnte am Beispiel der »Methode der Orte« experimentell bestätigt werden. Hierbei hat sich gezeigt, daß das Gehirn über große kognitive Kapazitätsreserven verfügt. In einer speziellen Testmethode (»testing the limits«) zeigt sich aber im Hochleistungsbereich, trotz der grundsätzlichen Plastizität, ein altersbezogenes Nachlassen der Gedächtnismechanik. Offenbar gibt es biologische Grenzen in der Schnelligkeit der menschlichen Vorstellungskraft. Vielleicht gelingt es auf der Grundlage dieser Erkentnnis, einen zuverlässigen Markierungsindikator für das hirnphysiologische Altern zu finden. Daraus könnten sich auch neue Methoden zur Früherkennung von Demenzen ableiten lassen.
Semantic processing from parafoveal words is an elusive phenomenon in alphabetic languages, but it has been demonstrated only for a restricted set of noncompound Chinese characters. Using the gaze-contingent boundary paradigm, this experiment examined whether parafoveal lexical and sublexical semantic information was extracted from compound preview characters. Results generalized parafoveal semantic processing to this representative set of Chinese characters and extended the parafoveal processing to radical (sublexical) level semantic information extraction. Implications for notions of parafoveal information extraction during Chinese reading are discussed.
The complexity of eye-movement control during reading allows measurement of many dependent variables, the most prominent ones being fixation durations and their locations in words. In current practice, either variable may serve as dependent variable or covariate for the other in linear mixed models (LMMs) featuring also psycholinguistic covariates of word recognition and sentence comprehension. Rather than analyzing fixation location and duration with separate LMMs, we propose linking the two according to their sequential dependency. Specifically, we include predicted fixation location (estimated in the first LMM from psycholinguistic covariates) and its associated residual fixation location as covariates in the second, fixation-duration LMM. This linked LMM affords a distinction between direct and indirect effects (mediated through fixation location) of psycholinguistic covariates on fixation durations. Results confirm the robustness of distributed processing in the perceptual span. They also offer a resolution of the paradox of the inverted optimal viewing position (IOVP) effect (i.e., longer fixation durations in the center than at the beginning and end of words) although the opposite (i.e., an OVP effect) is predicted from default assumptions of psycholinguistic processing efficiency: The IOVP effect in fixation durations is due to the residual fixation-location covariate, presumably driven primarily by saccadic error, and the OVP effect (at least the left part of it) is uncovered with the predicted fixation-location covariate, capturing the indirect effects of psycholinguistic covariates. We expect that linked LMMs will be useful for the analysis of other dynamically related multiple outcomes, a conundrum of most psychonomic research.
Messung von Blickbewegungen
(2006)
We compared effects of covert spatial-attention shifts induced with exogenous or endogenous cues on microsaccade rate and direction. Separate and dissociated effects were obtained in rate and direction measures. Display changes caused microsaccade rate inhibition, followed by sustained rate enhancement. Effects on microsaccade direction were differentially tied to cue class (exogenous vs. endogenous) and type (neutral vs. directional). For endogenous cues, direction effects were weak and occurred late. Exogenous cues caused a fast direction bias towards the cue (i.e., early automatic triggering of saccade programs), followed by a shift in the opposite direction (i.e, controlled inhibition of cue-directed saccades, leading to a 'leakage' of microsaccades in the opposite direction). (C) 2004 Elsevier Ltd. All rights reserved
It has recently been demonstrated that the presentation of a rare target in a visual oddball paradigm induces a prolonged inhibition of microsaccades. In the field of electrophysiology, the amplitude of the P300 component in event-related potentials (ERP) has been shown to be sensitive to the stimulus category (target vs. non target) of the eliciting stimulus, its overall probability, and the preceding stimulus sequence. In the present study we further specify the functional underpinnings of the prolonged microsaccadic inhibition in the visual oddball task, showing that the stimulus category, the frequency of a stimulus and the preceding stimulus sequence influence microsaccade rate. Furthermore, by co-recording ERPs and eye-movements, we were able to demonstrate that, despite being largely sensitive to the same experimental manipulation, the amplitude of P300 and the microsaccadic inhibition predict each other very weakly, and thus constitute two independent measures of the brain’s response to rare targets in the visual oddball paradigm.
It has recently been demonstrated that the presentation of visual oddballs induces a prolonged inhibition of microsaccades. The amplitude of the P300 component in event-related potentials (ERPs) has been shown to be sensitive to the category (target vs. nontarget) of the eliciting stimulus, its overall probability, and the preceding stimulus sequence. In the present study we further specify the functional underpinnings of the prolonged microsaccadic inhibition in the visual oddball task, showing that the stimulus category, the frequency of a stimulus, and the preceding stimulus sequence influence microsaccade rate. Furthermore, by co-recording ERPs and eye movements, we were able to demonstrate that, despite being largely sensitive to the same experimental manipulation, the amplitude of P300 and the microsaccadic inhibition predict each other only weakly.
Covert shifts of attention are usually reflected in RT differences between responses to valid and invalid cues in the Posner spatial attention task. Such inferences about covert shifts of attention do not control for microsaccades in the cue target interval. We analyzed the effects of microsaccade orientation on RTs in four conditions, crossing peripheral visual and auditory cues with peripheral visual and auditory discrimination targets. Reaction time was generally faster on trials without microsaccades in the cue-target interval. If microsaccades occurred, the target-location congruency of the last microsaccade in the cuetarget interval interacted in a complex way with cue validity. For valid visual cues, irrespective of whether the discrimination target was visual or auditory, target-congruent microsaccades delayed RT. For invalid cues, target-incongruent microsaccades facilitated RTs for visual target discrimination, but delayed RT for auditory target discrimination. No reliable effects on RT were associated with auditory cues or with the first microsaccade in the cue-target interval. We discuss theoretical implications on the relation about spatial attention and oculomotor processes.