A USER’S COGNITIVE WORKLOAD PERSPECTIVE IN NEGOTIATION SUPPORT SYSTEMS: AN EYE-TRACKING EXPERIMENT

Replying to several research calls, I report promising results from an initial experiment which com-pares different negotiation support system approaches concerning their potential to reduce a user’s cognitive workload. Using a novel laboratory-based non-intrusive objective measurement technique which derives the user’s cognitive workload from pupillary responses and eye-movements, I experi-mentally evaluated a standard, a chat-based, and an argumentation-based negotiation support system and found that a higher assistance level of negotiation support systems actually leads to a lower user’s cognitive workload. In more detail, I found that an argumentation-based system which fully automates the generation of the user’s arguments significantly decreases the user’s cognitive workload compared to a standard system. In addition I found that a negotiation support system implementing an additional chat function significantly causes higher cognitive workload for users compared to a standard system

PERSUASIVE PACKAGING: AN EYE-TRACKING APPROACH TO DESIGN

This dissertation details the development of a consensus-centered strategy for managing packaging design projects that enables designers from various fields to participate (seriously play) in the development process. The Work/Flow developed was quantified though a series of empirical eye-tracking experiments to determine if objects produced through the system resulted in longer fixation durations than the control. It was determined that packages developed through the Work/Flow were significantly more persuasive than the control (P \u3c 0.0005). The second experiment observed the effectiveness of designs produced through the Work/Flow in respect to the competitive retail array. Out of three product categories tested, one package was developed which garnered significantly different total fixation duration than the competition (P \u3c 0.0005). The remaining two packages failed to significantly attract attention more than the competitive array. However, the results showed that the designs developed did not differ, and thus all designs produced through the Work/Flow were as equally as persuasive against the competition. The dissertation details an intensive review of literature on three areas of study: serious design and play, participatory strategies, and rhetorical persuasion and seduction. The last chapter provides a detailed analysis and description of implementing the teaching and communicating the Work/Flow to professional packaging engineers, designers from various backgrounds, and academia

Sensory Manipulation as a Countermeasure to Robot Teleoperation Delays: System and Evidence

In the field of robotics, robot teleoperation for remote or hazardous environments has become increasingly vital. A major challenge is the lag between command and action, negatively affecting operator awareness, performance, and mental strain. Even with advanced technology, mitigating these delays, especially in long-distance operations, remains challenging. Current solutions largely focus on machine-based adjustments. Yet, there's a gap in using human perceptions to improve the teleoperation experience. This paper presents a unique method of sensory manipulation to help humans adapt to such delays. Drawing from motor learning principles, it suggests that modifying sensory stimuli can lessen the perception of these delays. Instead of introducing new skills, the approach uses existing motor coordination knowledge. The aim is to minimize the need for extensive training or complex automation. A study with 41 participants explored the effects of altered haptic cues in delayed teleoperations. These cues were sourced from advanced physics engines and robot sensors. Results highlighted benefits like reduced task time and improved perceptions of visual delays. Real-time haptic feedback significantly contributed to reduced mental strain and increased confidence. This research emphasizes human adaptation as a key element in robot teleoperation, advocating for improved teleoperation efficiency via swift human adaptation, rather than solely optimizing robots for delay adjustment.Comment: Submitted to Scientific Report

Kognitive Interpretationen mehrdeutiger visueller Reize

Unser Gehirn muss zu jeder Zeit relevante Signale von irrelevanten Informationen trennen. Dazu müssen diese als spezifische Einheiten erkannt und klassifiziert werden. Mehrdeutigkeit ist ein wesentlicher Aspekt dieses Verarbeitungsprozesses und kann durch verrauschte Eingangssignale und durch den Aufbau unserer sensorischer Systeme entstehen. Beispielsweise können Reize mehrdeutig sein, wenn sie verrauscht oder unvollständig sind oder nur kurzzeitig wahrgenommen werden. Unter solchen Bedingungen werden Wahrnehmung und Klassifikation eines Reizes deutlich erschwert. Bereits vorhandene kognitive Repräsentationen werden somit möglicherweise nicht aktiviert. Folglich müssen Rückschlüsse über die Reize aufgrund von Kontext und Erfahrung gezogen werden. Ein und derselbe Reiz kann jedoch unterschiedlich repräsentiert und im sensorischen System kodiert werden. Da nur eine Repräsentation die Basis zukünftigen Handelns bilden kann, entsteht eine Art Konkurrenz innerhalb der Wahrnehmung. Derartige Wahrnehmungsphänomene, die mit der Mehrdeutigkeit von Reizen in Verbindung stehen, bilden den Mittelpunkt der vorliegenden Dissertation. Wenn einem physikalisch konstanten Reiz mehrere Interpretationen zugeordnet werden, entsteht ein Wechsel zwischen diesen Einordnungen, den man wahrnimmt und Rivalität ("rivalry") nennt. In dieser Dissertation werden diverse neue Erkenntnisse zu diesem grundlegenden Phänomen der sensorischen Verarbeitung beschrieben. So wird gezeigt, dass Übergänge zwischen drei wahrgenommenen Interpretationen – ein vergleichsweise selten untersuchtes Phänomen, da Rivalität meist mit zweideutigen Reizen untersucht wird – vorhersehbaren Mustern folgen (Kapitel 2). Darüber hinaus zeigt sich, dass derartige Übergänge spezifische Eigenschaften aufweisen, welche die Geschwindigkeit und die Richtung ihrer räumlichen Ausbreitung im visuellen Feld bestimmen (Kapitel 3). Diese Eigenschaften der Mehrdeutigkeit werden weiterhin stark von Aufmerksamkeit und anderen, introspektiven Prozessen beeinflusst. Um die der Rivalität in der Wahrnehmung tatsächlich zugrundeliegenden Prozesse und die damit verbundenen Änderungen des Bewusstseins von derartigen subjektiven Prozessen abzugrenzen, müssen letztere kontrolliert oder sogar vollständig umgangen werden. Ein objektives Maß der Rivalität in der Wahrnehmung wird zur Lösung dieser Aufgabe vorgeschlagen und bietet eine wertvolle Alternative zu introspektivem Berichten über den Wahrnehmungszustand (Kapitel 4). Übergänge in der Wahrnehmung entstehen entlang einer bestimmten Merkmalsdimension des Reizes, wie beispielsweise der Orientierung des berühmten Neckerwürfels. Zudem kann auch eine Änderung in der Merkmalsdimension der Luminanz eine unterschiedliche Interpretation des Reizes hervorrufen. Es wird gezeigt, dass die Pupille kleiner wird, wenn eine Interpretation mit hoher Luminanz die Wahrnehmung übernimmt, und umgekehrt, dass die Pupille größer wird, wenn eine Interpretation mit niedriger Luminanz die Wahrnehmung übernimmt. Folglich kann die Pupille als ein zuverlässiges und objektives Maß für Änderungen in der Wahrnehmung verwendet werden. Durch die Verwendung solcher objektiven Maße konnten neue Eigenschaften der Übergänge in der Wahrnehmung aufgezeigt werden, welche die Theorie unterstützen, dass Introspektion die der Verarbeitung mehrdeutiger Situationen zugrundeliegenden Prozesse merklich beeinflussen kann. Als Nächstes wurden mehrdeutiger Reize im Zusammenhang mit der Wahrnehmung von Objekten eingesetzt (Kapitel 5). Am Beispiel der Kippfigur des "bewegten Diamanten" wird dabei die Bedeutung von mehrdeutigen Reizen veranschaulicht. Beim bewegten Diamanten werden zwei Interpretationen wahrgenommen, die sich entlang der Dimension der Objektkohärenz abwechseln. Das bedeutet, dass die Wahrnehmung zwischen einem einzelnen zusammenhängenden Objekt (Diamant) und mehreren unzusammenhängenden Komponenten kippt. Es wird gezeigt, dass die Interpretation des Reizes als ein einziges kohärentes Objekt, verglichen mit der Interpretation als mehrere Komponenten, zu einer Erhöhung der visuellen Empfindlichkeit innerhalb des Objektes führt. Diese Ergebnisse sind ein Beleg dafür, wie die Aktivierung einer Interpretation eines Reizes als Einzelobjekt (im Vergleich zur Komponentenwahrnehmung) dazu führt, dass die Aufmerksamkeit top-down zu den relevanten Bereichen des Gesichtsfeldes gelenkt wird. Es wird weiter untersucht, welche Eigenschaften des Reizes zu einer bottom-up Aktivierung der Interpretation solcher Objekte beitragen (Kapitel 6). Die Mehrdeutigkeit von Objekten kann erfolgreich aufgehoben werden, indem man einen starken Kontrast in Luminanz oder Farbe zwischen dem Objekt und dem Hintergrund erzeugt. Auch die Größe und die Form haben einen großen Einfluss auf die Detektion und Identifikation von Objekten. Des Weiteren sind die Eigenschaften eines Objektes nicht nur bestimmend für die Erfolgsquote bei der Objekterkennung, sondern ebenso bedeutend für die Speicherung der Repräsentation im Gedächtnis, beispielsweise von neu wahrgenommenen Objekten. Das Klassifizieren von Objekten durch die Versuchsperson wird ebenfalls durch Mehrdeutigkeit beeinflusst. So kann ein Objekt der Versuchsperson einerseits als neu erscheinen, obwohl es bereits bekannt war, weil es beispielsweise der Versuchsperson schon einmal gezeigt worden ist. Andererseits kann auch ein eigentlich unbekanntes Objekt der Versuchsperson dennoch vertraut vorkommen. In dieser Arbeit wird gezeigt, dass solche subjektiven Effekte einen Einfluss auf die Pupillengröße haben (Kapitel 7). Außerdem verkleinert sich die Pupille der Versuchspersonen beim Betrachten neuer Bilder stärker als bei bekannten. Ein ähnlicher Effekt wird gefunden, wenn das Bild vorher erfolgreich im Gedächtnis gespeichert wurde. Daher ist es wahrscheinlich, dass die Pupille die Verfestigung von neuen Objekten im Gedächtnis widerspiegelt. Abschließend wird untersucht, ob sich kognitive Prozesse, wie Entscheidungsfindung – ein wichtiger Prozess, falls mehreren Optionen zur Verfügung stehen und Mehrdeutigkeit aufgehoben werden soll – auch in der Pupille widerspiegeln (Kapitel 8). Es wird zunächst bestätigt, dass die Pupillen sich erweitern, nachdem man eine Entscheidung getroffen hat. Neu wird gezeigt, dass diese Pupillenausdehnungen erfolgreich von anderen Personen erkannt und verwendet werden können, um ein interaktives Spiel gegen die erste Person (den "Gegner") zu gewinnen. Insgesamt wird in dieser Dissertation untersucht, wie mehrdeutige Reize die Wahrnehmung beeinflussen und wie Mehrdeutigkeit verwendet werden kann, um Prozesse des Gehirns zu studieren. Es hat sich gezeigt, dass Mehrdeutigkeit vorhersehbaren Mustern folgt, sie objektiv mit Reflexen gemessen werden kann, und Einblicke in neuronale Prozesse wie Aufmerksamkeit, Objektwahrnehmung und Entscheidungsmechanismen liefern kann. Diese Ergebnisse zeigen, dass Mehrdeutigkeit eine zentrale Eigenschaft sensorischer Systeme ist, und Lebewesen in die Lage versetzt, mit ihrer Umwelt flexibel zu interagieren. Mehrdeutigkeit macht das Verhalten vielfältiger, ermöglicht es dem Gehirn, mit der Welt auf verschiedenen Wegen zu interagieren, und ist die Basis der Dynamik von Wahrnehmung, Interpretation und Entscheidung.Brains can sense and distinguish signals from background noise in physical environments, and recognize and classify them as distinct entities. Ambiguity is an inherent part of this process. It is a cognitive property that is generated by the noisy character of the signals, and by the design of the sensory systems that process them. Stimuli can be ambiguous if they are noisy, incomplete, or only briefly sensed. Such conditions may make stimuli indistinguishable from others and thereby difficult to classify as single entities by our sensory systems. In these cases, stimuli fail to activate a representation that may have been previously stored in the system. Deduction, through context and experience, is consequently needed to reach a decision on what is exactly sensed. Deduction can, however, also be subject to ambiguity as stimuli and their properties may receive multiple representations in the sensory system. In such cases, these multiple representations compete for perceptual dominance, that is, for becoming the single entity taken by the system as a reference point for subsequent behavior. These types of ambiguity and several phenomena that relate to them are at the center of this dissertation. Perceptual rivalry, the phenomenal experience of alternating percepts over time, is an example of how the brain may give multiple interpretations to a stimulus that is physically constant. Rivalry is a very typical and general sensory process and this thesis demonstrates some newly discovered properties of its dynamics. It was found that alternations between three perceptual interpretations – a relatively rare condition as rivalry generally occurs between two percepts – follow predictable courses (Chapter 2). Furthermore, such alternations had several properties that determine their speed and direction of spatial spread (suppression waves) in the visual field (Chapter 3). These properties of ambiguity were further strongly affected by attention and other introspective processes. To demarcate the true underlying process of perceptual rivalry and the accompanied changes in awareness, these subjective processes need to be either circumvented or controlled for. An objective measure of perceptual rivalry was proposed that resolved this issue and provided a good alternative for introspective report of ambiguous states (Chapter 4). Changes in percepts occur along a specific feature domain such as depth orientation for the famous Necker cube. Alternatively, luminance may also be a rivalry feature and one percept may appear brighter as the other rivaling percept. It was demonstrated that the pupil gets smaller when a percept with high luminance becomes dominant, and vice versa, gets bigger when a percept with low luminance gets dominant during perceptual rivalry. As such, the pupil can serve as a reliable objective indicator of changes in visual awareness. By using such reflexes during rivalry, several new properties of alternations were discovered and it was again confirmed that introspection can confound the true processes involved in ambiguity. Next, the usefulness of ambiguous stimuli was explored in the context of objects as entities (Chapter 5). Some ambiguous stimuli can induce two percepts that alternate along the feature domain of object coherency, that is, whether a single coherent object or multiple incoherent objects are seen. In other words, an ambiguous stimulus can induce two cognitive interpretations of either seeing an entity or not. It was reported that being aware of a single coherent object results in the increase in visual sensitivity for the areas that constitute the object. These results are evidence of how the activation of a representation of a single and unique object can guide and allocate attentional resources to relevant areas in the visual field in a top-down way. It was further explored which features help to bottom-up access such object representations (Chapter 6). Ambiguity of objects can be successfully resolved by adding strong contrasts between the object and its background in luminance and color. The size and variability of the object's shape was also found to be an important factor for its successful detection and identification. Furthermore, the characteristics of objects do not only determine the rate of success in a recognition task, but are equally important for the storage of their representations in memory if, for instance, the object is novel to the observer. The subjective experience of a novel object is also subject to ambiguity and objects may appear novel to the observer although they are familiar (i.e., previously shown to the observer), or vice versa, they appear familiar to the observer although they are actually novel. It was here shown that such subjective effects are reflected in the pupil (Chapter 7). In addition, if novel images were presented to observers, their pupils constricted stronger as compared to if familiar images were presented. Similarly, if novel stimuli were shown to observers, pupillary constrictions were stronger if these stimuli were successfully stored in memory as compared to those later forgotten. As such, the pupil reflected the cognitive process of novelty encoding. Finally, it was tested whether other cognitive processes, such as decision-making – an important process when multiple options are available and ambiguity has to be resolved with a conscious decision – were also reflected in changes of pupil size (Chapter 8). It was confirmed that the pupil tends to dilate after an observer has made a decision. These dilations can successfully be detected between individuals and further used to gain the upper hand during an interactive game. In sum, this thesis has explored how ambiguous signals affect perception and how ambiguity inside perceptual systems can be used to study processes of the brain. It is found that ambiguity follows predictable courses, can be objectively assessed with reflexes, and can provide insights into other neuronal mechanisms such as attention, object representations, and decision-making. These findings demonstrate that ambiguity is a core property of the sensory systems that enable living beings to interact with their surroundings. Ambiguity adds variation to behavior, allows the brain to flexibly interact with the world, and lies at the bottom of the dynamics of sense, interpretations, and behavioral decisions

Non-Intrusive Affective Assessment in the Circumplex Model from Pupil Diameter and Facial Expression Monitoring

Automatic methods for affective assessment seek to enable computer systems to recognize the affective state of their users. This dissertation proposes a system that uses non-intrusive measurements of the user’s pupil diameter and facial expression to characterize his /her affective state in the Circumplex Model of Affect. This affective characterization is achieved by estimating the affective arousal and valence of the user’s affective state. In the proposed system the pupil diameter signal is obtained from a desktop eye gaze tracker, while the face expression components, called Facial Animation Parameters (FAPs) are obtained from a Microsoft Kinect module, which also captures the face surface as a cloud of points. Both types of data are recorded 10 times per second. This dissertation implemented pre-processing methods and fixture extraction approaches that yield a reduced number of features representative of discrete 10-second recordings, to estimate the level of affective arousal and the type of affective valence experienced by the user in those intervals. The dissertation uses a machine learning approach, specifically Support Vector Machines (SVMs), to act as a model that will yield estimations of valence and arousal from the features derived from the data recorded. Pupil diameter and facial expression recordings were collected from 50 subjects who volunteered to participate in an FIU IRB-approved experiment to capture their reactions to the presentation of 70 pictures from the International Affective Picture System (IAPS) database, which have been used in large calibration studies and therefore have associated arousal and valence mean values. Additionally, each of the 50 volunteers in the data collection experiment provided their own subjective assessment of the levels of arousal and valence elicited in him / her by each picture. This process resulted in a set of face and pupil data records, along with the expected reaction levels of arousal and valence, i.e., the “labels”, for the data used to train and test the SVM classifiers. The trained SVM classifiers achieved 75% accuracy for valence estimation and 92% accuracy in arousal estimation, confirming the initial viability of non-intrusive affective assessment systems based on pupil diameter and face expression monitoring

The Usefulness of Multi-Sensor Affect Detection on User Experience: An Application of Biometric Measurement Systems on Online Purchasing

abstract: Traditional usability methods in Human-Computer Interaction (HCI) have been extensively used to understand the usability of products. Measurements of user experience (UX) in traditional HCI studies mostly rely on task performance and observable user interactions with the product or services, such as usability tests, contextual inquiry, and subjective self-report data, including questionnaires, interviews, and usability tests. However, these studies fail to directly reflect a user’s psychological involvement and further fail to explain the cognitive processing and the related emotional arousal. Thus, capturing how users think and feel when they are using a product remains a vital challenge of user experience evaluation studies. Conversely, recent research has revealed that sensor-based affect detection technologies, such as eye tracking, electroencephalography (EEG), galvanic skin response (GSR), and facial expression analysis, effectively capture affective states and physiological responses. These methods are efficient indicators of cognitive involvement and emotional arousal and constitute effective strategies for a comprehensive measurement of UX. The literature review shows that the impacts of sensor-based affect detection systems to the UX can be categorized in two groups: (1) confirmatory to validate the results obtained from the traditional usability methods in UX evaluations; and (2) complementary to enhance the findings or provide more precise and valid evidence. Both provided comprehensive findings to uncover the issues related to mental and physiological pathways to enhance the design of product and services. Therefore, this dissertation claims that it can be efficient to integrate sensor-based affect detection technologies to solve the current gaps or weaknesses of traditional usability methods. The dissertation revealed that the multi-sensor-based UX evaluation approach through biometrics tools and software corroborated user experience identified by traditional UX methods during an online purchasing task. The use these systems enhanced the findings and provided more precise and valid evidence to predict the consumer purchasing preferences. Thus, their impact was “complementary” on overall UX evaluation. The dissertation also provided information of the unique contributions of each tool and recommended some ways user experience researchers can combine both sensor-based and traditional UX approaches to explain consumer purchasing preferences.Dissertation/ThesisDoctoral Dissertation Human Systems Engineering 201

Effects of online advertising on children's visual attention and task performance during free and goal-directed internet use : A media psychology approach to children's website interaction and advert distraction

This dissertation consists of four eye-tracking studies that investigate how salient online advertising and children's level of executive function contributes to their advert distraction. In Study 1, children aged 9 were instructed to surf freely on the internet while all advert material appearing on-screen was registered. The analyses examined how perceptual prominence in each online advert was related to children's visual attention. In Study 2, a mock-up advergame website was designed with controlled advert conditions, and children aged 9 and 12 were instructed to solve a number of in-game tasks. This study investigated the combined effects of perceptual prominence (e.g. abrupt onset) and content relevance (e.g. personalized content) on children's advert distraction. The results of the first two studies showed significant positive effects of advert saliency on children's visual attention. Due to the task-oriented research design used in the second study, it was possible to interpret these effects on visual attention in terms of advert distraction. Both studies showed that higher levels of inhibitory control in children significantly decreased the effects of advert saliency on visual attention and advert distraction.The following two studies, investigated how advert animation affected children's online reading comprehension and information search on commercial websites. In Study 3, children aged 9 were presented with factual texts that they were instructed to read in order to answer comprehension questions. Each text was presented on a web page which also featured static or animated online adverts. In Study 4, children aged 9 were instructed to solve two online task types featuring concurrent online advertising: reading and information search. The results of these studies showed that animated online advertising had significant negative effects on children's task performance. In the third study, it was found that animated adverts had a negative effect on children's reading comprehension, and that this negative effect was stronger among children with low levels of inhibitory control. The fourth study found that advert animation had a significant positive effect on children's cognitive load across task types. Taken together, this dissertation project has studied children's online advert distraction in a wide range of realistic internet usage situations

VIP: A UNIFYING FRAMEWORK FOR COMPUTATIONAL EYE-GAZE RESEARCH

Ph.DDOCTOR OF PHILOSOPH