In this study the mechanisms that control attention in natural scenes was examined. It was explored whether familiarity with the environment makes participants more sensitive to changes or novel events in the scene. Previous investigation of this issue has been based on viewing 2D pictures/images of simple objects or of natural scenes, a situation which does not accurately reflect the challenges of natural vision. In order to examine this issue, as well as the differences between 2D and 3D environments, two experiments were designed in which the general task demands could be manipulated. The results revealed that familiarity with the environment significantly increased the time spent fixating regions in the scene where a change had occurred. The results support the hypothesis that we learn the structure of natural scenes over time, and that attention is attracted by deviations from the stored scene representation. Such a mechanism would allow attention to objects or events that were not explicitly on the current cognitive agenda.

This thesis is about diagrammatic reasoning and error-finding in conceptual modeling diagrams. Specifically, the differences of the cognitive strategies and behaviors of notation-familiar participants versus domain-familiar participants working on conceptual modeling diagrams are inspected. The domain-familiar participants are experienced in the topic being represented, but they do not have any formal training in software development representations. On the other hand, the notation-familiar participants are educated in software representations, but unfamiliar with the topic represented. The main experiment and the follow-up experiment also aim to study how some properties of diagrams affect the error-finding behaviors. The participant groups&rsquo / performances in the main experiment are investigated and compared by the analysis of verbal protocol data and eye movement data. The combination of the two different methods enhances detailed analyses. In the follow-up experiment, only eye movement data is involved to evaluate how some properties of diagrams affect problem-solving. By means of both experiments, it is concluded that diagrammatic complexity has a negative effect on reasoning whereas the degree of causal chaining improves diagrammatic reasoning. In the main experiment, some differences in the diagrammatic reasoning processes between the groups are observed, too. The notation-familiar participants are observed to be more successful in error-finding although they are unfamiliar with the topic. This study underlines the interaction of cognitive science and software engineering by integrating eye movement data, verbal protocol analysis and performance data into the cognitive inspection of software engineering notations.

This study aims to investigate the effects of event type (concepts represented by the graph) in graph comprehension with three graph types (line, bar, area) and two graph designs (linear, round) by means of two different task types (trend assessment, discrete comparison). A novel round graph type was designed for that purpose. Five hypotheses were investigated: H1: Graph type affects comparison strategies / H2: Event type affects comparison strategies / H3: Graph design affects comparison strategies / H4: Graph design and event type interact / H5: Task type affects comparison strategies. As a method to collect data on subjects&#039 / graph perception and comprehension, behavioral (recollected values, word preferences in the description task) and eye-tracking data (scan paths, gaze length, number of fixation, fixation duration and number of transitions) were collected. As an outcome of this thesis, while the event type and the task type seemed to affect the graph comprehension, the effect of graph type, the graph design and interaction between graph design and event type were partially observed. These results point out that although round and linear graph designs are informationally equivalent, the round graphs are computationally better suited than linear graphs for the interpretation of cyclic concepts. However, grasping trend information for the linear events and making discrete comparisons were achieved with the same effort in both graph designs. This result is not trivial at all, given the fact that participants were not familiar with the round graph design and were confronted with them in this experiment for the first time.

In this study, Concept map (CM) development processes of the experts and novices were explored. This studyaimed to investigate the similarities and differences among novices and experts&rsquo / CM development process regarding their cognitive processes. Two experiments were designed / eye-tracking, written and verbal data were collected from 29 pre-service teachers and 6 subject matter experts.Data were analyzed by using qualitative and quantitative data analysis methods. The results indicated that eventhough some of the strategies were similar, there were different patterns followed by the experts and novices during the CM development process. Both experts and novices embraced &lsquo / deductive reasoning&rsquo / , and preferred &lsquo / hierarchical&rsquo / type of CMs. The other patterns recognized during the process were&lsquo / filling information in an order&rsquo / , &lsquo / branch construction pattern&rsquo / ,&lsquo / content richness&rsquo / and &lsquo / progress pattern&rsquo / . Novices and experts were distinguished in their content richness measures which used to determine the quality of the maps. Regarding the progress pattern, novices and experts differed in terms of the frequency and duration for specific acts invarious phases of their progress in CM development process. Furthermore, expert participants differed from novices in their fixation count numbers, fixation durations, visit duration periods for specific actions. Fixation count numbers of the novices were higher than the experts during the entire process and in specific dimensions of the CM development process. As a conclusion, these pattern differences affect the CM development process directly and the instructors need to give emphasis to these critical points while using CM during the instruction, and with the help of these pattern differences, instructors could guide the learner effectively and acquire content rich CMs.

In order to attract the attention of users current online shopping environments often involve the use of dynamic display changes such as animation, flashing or rotating text, and pop-up boxes. While there is some experimental evidence that supports the effectiveness of such changes for the purpose of capturing attention, such changes might also distract the user and hinder task performance. Thus, a key usability challenge for the designers of such environments involves balancing the need to attract attention with the desire to minimize any interruption of the performance of users. To date there is very little systematic investigation of the influence of display changes on consumers¡¦ attention and decisions during the browsing of online shopping web sites. The main goal of the present experiments was to research factors that might be important in determining the influence of such display changes. To accomplish that experimental tasks were created that resembled some aspects of the visual decision process and dynamic changes that occur during online shopping. However, in order to permit greater experimental control, the information environment used in the present tasks was substantially simplified as compared to online environments. Specifically, in 3 experiments, participants¡¦ eye movements were monitored while they chose between 2 alternatives, each represented by a set of visual images, with one set placed on the top of the screen and the other on the bottom. Immediately prior to this decision participants performed one or more binary decisions based on subsets of these images. On some trials, images were spatially swapped in the display presented during the final decision as compared to a prior presentation. Across experiments, we manipulated the relevance of the change to task performance as well as the recency of the information that was modified. By analyzing behavioral and eye movement measures, we documented evidence that participants flexibly and effectively accommodated to a variety of display changes. However, there was cost associated with display changes in the form of longer viewing times. In addition, task relevant changes and changes to recently viewed information were generally more disruptive. We discuss the implications of the present findings for the design of online shopping web sites and for future research that would attempt to generalize the present findings to more complex and more realistic online environments.

Does visual recognition entail verifying an idea about what is perceived? This question was addressed in the three studies of this thesis. The main hypothesis underlying the investigation was that visual recognition is an active process involving hypothesis testing. Recognition of faces (Study 1), scenes (Study 2) and objects (Study 3) was investigated using eye movement registration as a window on the recognition process. In Study 1, a functional relationship between eye movements and face recognition was established. Restricting the eye movements reduced recognition performance. In addition, perceptual reinstatement as indicated by eye movement consistency across study and test was related to recollective experience at test. Specifically, explicit recollection was related to higher eye movement consistency than familiarity-based recognition and false rejections (Studies 1-2). Furthermore, valid expectations about a forthcoming stimulus scene produced eye movements which were more similar to those of an earlier study episode, compared to invalid expectations (Study 2). In Study 3 participants recognized fragmented objects embedded in nonsense fragments. Around 8 seconds prior to explicit recognition, participants began to fixate the object region rather than a similar control region in the stimulus pictures. Before participants’ indicated awareness of the object, they fixated it with an average of 9 consecutive fixations. Hence, participants were looking at the object as if they had recognized it before they became aware of its identity. Furthermore, prior object information affected eye movement sampling of the stimulus, suggesting that semantic memory was involved in guiding the eyes during object recognition even before the participants were aware of its presence. Collectively, the studies support the view that gaze control is instrumental to visual recognition performance and that visual recognition is an interactive process between memory representation and information sampling.

Describing human eye movement behavior as an alternating sequence of saccades and fixations turns out to be an oversimplification because the eyes continue to move during fixation. Small-amplitude saccades (e.g., microsaccades) are typically observed 1-2 times per second during fixation. Research on microsaccades came in two waves. Early studies on microsaccades were dominated by the question whether microsaccades affect visual perception, and by studies on the role of microsaccades in the process of fixation control. The lack of evidence for a unique role of microsaccades led to a very critical view on the importance of microsaccades. Over the last years, microsaccades moved into focus again, revealing many interactions with perception, oculomotor control and cognition, as well as intriguing new insights into the neurophysiological implementation of microsaccades. In contrast to early studies on microsaccades, recent findings on microsaccades were accompanied by the development of models of microsaccade generation. While the exact generating mechanisms vary between the models, they still share the assumption that microsaccades are generated in a topographically organized saccade motor map that includes a representation for small-amplitude saccades in the center of the map (with its neurophysiological implementation in the rostral pole of the superior colliculus). In the present thesis I criticize that models of microsaccade generation are exclusively based on results obtained during prolonged presaccadic fixation. I argue that microsaccades should also be studied in a more natural situation, namely the fixation following large saccadic eye movements. Studying postsaccadic fixation offers a new window to falsify models that aim to account for the generation of small eye movements. I demonstrate that error signals (visual and extra-retinal), as well as non-error signals like target eccentricity influence the characteristics of small-amplitude eye movements. These findings require a modification of a model introduced by Rolfs, Kliegl and Engbert (2008) in order to account for the generation of small-amplitude saccades during postsaccadic fixation. Moreover, I present a promising type of survival analysis that allowed me to examine time-dependent influences on postsaccadic eye movements. In addition, I examined the interplay of postsaccadic eye movements and postsaccadic location judgments, highlighting the need to include postsaccadic eye movements as covariate in the analyses of location judgments in the presented paradigm. In a second goal, I tested model predictions concerning preparatory influences on microsaccade generation during presaccadic fixation. The observation, that the preparatory set significantly influenced microsaccade rate, supports the critical model assumption that increased fixation-related activity results in a larger number of microsaccades. In the present thesis I present important influences on the generation of small-amplitude saccades during fixation. These eye movements constitute a rich oculomotor behavior which still poses many research questions. Certainly, small-amplitude saccades represent an interesting source of information and will continue to influence future studies on perception and cognition. / Die Beschreibung des Blickbewegungsverhaltens als eine sich abwechselnde Folge von Sakkaden und Fixationen stellt eine starke Vereinfachung dar, denn auch während einer Fixation bewegen sich die Augen. Typischerweise treten Bewegungen von kleiner Amplitude (z.B. Mikrosakkaden), 1-2 mal pro Sekunde während einer Fixation auf. Frühe Studien zu Mikrosakkaden wurden von Fragen bezüglich des Einflusses von Mikrosakkaden auf die visuelle Wahrnehmung, und Studien zu der Rolle von Mikrosakkaden bei der Fixationskontrolle dominiert. Fehlende Evidenz für eine Rolle, die ausschließlich Mikrosakkaden zufällt, führten zu einer sehr kritischen Betrachtung von Mikrosakkaden. In den letzten Jahren rückten Mikrosakkaden wieder mehr in den Fokus. Vielerlei Zusammenhänge mit Wahrnehmung, okulomotorischer Kontrolle und Kognition, sowie neue Erkenntnisse bezüglich der neurophysiologischen Implementierung von Mikrosakkaden konnten aufgedeckt werden. In den letzten Jahren wurden verschiedene Modelle der Mikrosakkadengenerierung vorgestellt. Auch wenn sich diese in ihren exakten Mechanismen unterscheiden, so teilen sie doch die Annahme, dass Mikrosakkaden in einer topographisch organisierten motorischen Karte für Sakkaden ausgelöst werden. Diese Karten beinhalten eine Repräsentation für klein-amplitudige Sakkaden im Zentrum der Karte (mit dem rostralen Pol der colliculi superiores als neurophysiologische Implementierung). In der vorliegenden Arbeit kritisiere ich, dass Modelle der Mikrosakkadengenerierung ausschließlich auf Resultaten langanhaltender präsakkadischer Fixation beruhen. Ich führe an, dass Mikrosakkaden in einer natürlicheren Situation untersucht werden sollten, nämlich während der Fixation nach einer großen Sakkade. Die Untersuchung postsakkadischer Fixation bietet eine neue Möglichkeit Modelle der Mikrosakkadengenerierung zu falsifizieren. In den Studien zeige ich, dass Signale über den Fehler in der Sakkadenlandeposition (visuelle und extra-retinale), sowie fehler-unabhängige Signale, wie die Zielreiz-Exzentrizität, einen entscheidenden Einfluss auf kleine Sakkaden haben. Diese Resultate erfordern Modifikationen an dem kürzlich eingeführten Modell von Rolfs, Kliegl und Engbert (2008), um die Generierung von kleinen Sakkaden auch während der postsakkadischen Fixation erklären zu können. Darüber hinaus präsentiere ich eine viel versprechende Ereigniszeitanalyse, die uns erlaubt zeitabhängige Einflüsse auf das postsakkadische Blickbewegungsverhalten zu untersuchen. Außerdem untersuche ich das Zusammenspiel von postsakkadischen Augenbewegungen und postsakkadischen Positionsurteilen. Dabei wird die Bedeutung von postsakkadischen Augenbewegungen als Kovariate in den statistischen Analysen betont. Ein zweites Ziel dieser Arbeit besteht darin Modellvorhersagen bezüglich vorbereitender Einflüsse auf die Mikrosakkadengenerierung zu untersuchen. Die Ergebnisse, hinsichtlich eines signifikanten Einflusses des preparatory set auf die Mikrosakkadenrate unterstützt die wesentliche Modellannahme, dass erhöhte fixationsbezogene Aktivität zu einer größeren Anzahl an Mikrosakkaden führt. In der vorliegenden Arbeit präsentiere ich wichtige Einflüsse auf die Generierung von kleinen Sakkaden während der Fixation. Diese Augenbewegungen stellen ein vielseitiges okulomorisches Verhalten dar, welche weiterhin zahlreiche Fragen mit sich bringen und sicherlich zukünftige Studien zu Wahrnehmung und Kognition beeinflussen werden.

The theme of Master project of Electronical engineer is actual, because humans vision depends on possibility to perform sacadic eye movements and orient the eye so, that person could see concern targets in the view. The main sacadic movements use precipitated studies of characterizing their features. The purpose of the theme is to find what can eye movements show about rewiew and perception of the view. Experiments are performed using contact-free eye movement research method. During experiment was filmed the eye of the investigative person. In the work we wiewed ower methods of eye movement research and earlier performed eye movements research during review of the view. Also we performed two new experiments and did such conclusions: 1. Persons can control sacadic movement and instead of one movement to memorized target (when primary review is available) is performing some sakades, who are typical. In most primary review cases the error of final point is lesser. 2. We proved hypothesis, which says that viewing over objects the look is shifted to places, who can give more information. 3. We proved hypothesis, which says that in the case of continually alterativing similar views arises lasstitude, which smoothes perception. The results of experiments we can use in computer adaptabillity for disable persons, publicity, warning signs, creation of automobiles and et. c.

Žmogaus akių judesiai yra plačiai tyrinėjami ir taikomi praktikoje. Jie yra labai informatyvūs, todėl jais domisi įvairių sričių mokslininkai. Atskiri akių judesių parametrai yra tyrinėjimo objektai daugelyje mokslo sričių. Vienur akių judesiai patys yra tyrimo objektas, kituose yra tiriamas akių judesių vaidmuo regėjimo procese ir dar kituose akių judesių analizė naudojama sudėtingesnių žmogaus veiklos formų tyrime. Tokių sudėtingų uždavinių sprendimas neįmanomas be atitinkamų algoritmų sudarymo ir jų kompiuterinio modeliavimo. Darbo tikslas – sukurti programinę įrangą žmogaus akių sukties judesių modeliavimui ir rezultatų pateikimui. Darbe pateikiami žmogaus akių judesių tipai, jų matematinio aprašymo, registravimo ir pateikimo būdai. Taip pat aprašomas akies sukties judesių matavimo elektromagnetiniu metodu matematinis modelis. Siekiant geresnių rezultatų kuriant programinę įrangą, atliktas tyrimas nustatymui, kokie programavimo įrankiai plačiausiai taikomi akių judesių analizei. Pateikiami modeliavimo sistemos projektavimo etapai, keliami funkciniai reikalavimai, reikalavimai duomenims, sistemos išvaizdai, panaudojimui, pritaikymui. Aprašoma modeliavimo eiga ir sistemos testavimo rezultatai. Nurodomi sukurtos sistemos trūkumai ir keliai tolimesniam vystymui. Galutinis darbo rezultatas – sukurta programinė įranga akių sukties judesiams, įrašytiems elektromagnetiniu būdu, modeliuoti ir paruošti pradinius duomenis tolimesnei analizei. / Human eye movements are widely studied and applied in practice. They are very informative, and therefore they are interested in various fields of scientists. Individual parameters of the eye movements of research facilities in many scientific fields. Some eye movements are themselves the subject of the investigation, the other is studied eye movements of the role of vision and the other motion analysis using more sophisticated forms of human activity study. Such complex tasks can not be processed without the appropriate algorithms and their computer simulation. The aim - to create the software of human torsion eye movements modeling and presentation of results. The work presents the types of human eye movements, their mathematical description, recording and presentation techniques. It also describes the torsion eye movements measuring with electromagnetic method mathematical model. In order to better results in software development, a survey of the most widely applied tools of programming eye movements analysis. The design stages of simulation system, the functional requirements, data requirements, system appearance, recovery, adaptation are described. Describes the modeling process and system test results. Refer to the shortcomings of created system and ways for further development. Final result - designed software to the torsion eye movements recorded electromagnetically modeling, and preparation of baseline data for further analysis.

During reading oculomotor processes guide the eyes over the text. The visual information recorded is accessed, evaluated and processed. Only by retrieving the meaning of a word from the long-term memory, as well as through the connection and storage of the information about each individual word, is it possible to access the semantic meaning of a sentence. Therefore memory, and here in particular working memory, plays a pivotal role in the basic processes of reading. The following dissertation investigates to what extent different demands on memory and memory capacity have an effect on eye movement behavior while reading. The frequently used paradigm of the reading span task, in which test subjects read and evaluate individual sentences, was used for the experimental review of the research questions. The results speak for the fact that working memory processes have a direct effect on various eye movement measurements. Thus a high working memory load, for example, reduced the perceptual span while reading. The lower the individual working memory capacity of the reader was, the stronger was the influence of the working memory load on the processing of the sentence. / Beim Lesen steuern okulomotorische Prozesse die Blickbewegungen über den Text. Die aufgenommenen visuellen Informationen werden erschlossen, beurteilt und verarbeitet. Erst durch den Abruf der Wortbedeutung aus dem Langzeitgedächtnis, und die Verknüpfung sowie Speicherung der einzelnen Wortinformationen erschließt sich die semantische Bedeutung eines Satzes. Somit stellt das Gedächtnis und hier insbesondere das Arbeitsgedächtnis eines der grundlegenden Prozesse für das Lesen dar. Die vorliegende Dissertation untersucht inwieweit sich unterschiedliche Gedächtnisanforderungen und Gedächtniskapazitäten auf das Blickverhalten während des Lesens auswirken. Für die experimentelle Überprüfung der Forschungsfragen wurde das in der Arbeitsgedächtnisforschung sehr häufig genutzte Paradigma der Lesespannenaufgabe verwendet, bei dem Probanden einzelne Sätze lesen und beurteilen. Die Ergebnisse sprechen für einen direkten Einfluss von Arbeitsgedächtnisprozessen auf verschiedene Blickbewegungsmaße. So reduzierte eine hohe Arbeitsgedächtnisbelastung beispielsweise die perzeptuelle Spanne während des Lesens. Je geringer die individuelle Arbeitsgedächtniskapazität des Lesers war, desto stärker war der Einfluss der Arbeitsgedächtnisbelastung auf die Satzverarbeitung.