Study of an Extensive Set of Eye Movement Features: Extraction Methods and Statistical Analysis

This work presents a study of an extensive set of 101 categories of eye movement features from three types of eye movement events: fixations, saccades, and post-saccadic oscillations. We present a unified framework of methods for the extraction of features that describe the temporal, positional and dynamic characteristics of eye movements. We perform statistical analysis of feature values by employing eye movement data from a normative population of 298 subjects, recorded during a text reading task. We present overall measures for the central tendency and variability of feature values, and we quantify the test-retest reliability of features using either the Intraclass Correlation Coefficient (for normally distributed and normalized features) or Kendall’s coefficient of concordance (for non-normally distributed features). Finally, for the case of normally distributed and normalized features we additionally perform factor analysis and provide interpretations of the resulting factors. The presented methods and analysis can provide a valuable tool for researchers in various fields that explore eye movements, such as in behavioral studies, attention and cognition research, medical research, biometric recognition, and human-computer interaction

Γραμματισμός και Παραπληροφόρηση: Η περίπτωση των εμβολίων κατά της Covid - 19

Στην εργασία με τίτλο Γραμματισμός και Παραπληροφόρηση διερευνάται η κατασκευή και διαπραγμάτευση νοημάτων σε ειδησεογραφικά κείμενα με θέμα τον εμβολιασμό κατά της Covid - 19 που ελέγχονται ως παραπληροφορητικά. Παράλληλα, εξετάζονται οι διαδικασίες σχεδιασμού νοημάτων στα κείμενα που τους ασκούν τον έλεγχο και στα σχόλια του κοινού γύρω από αυτά. Έπειτα από μία επισκόπηση της έρευνας με θέμα το δημοσιογραφικό λόγο (ή λόγο των Μέσων), η εργασία επικεντρώνεται στις έννοιες της σκόπιμης παραπληροφόρησης (disinformation), των ψευδών ειδήσεων (fake news) και των μυθευμάτων (myths) που κυριαρχούν στο πλαίσιο των σημερινών μετανεωτερικών, μετα-αληθειακών (post-truth) κοινωνιών. Οι επικοινωνιακές αλληλεπιδράσεις που συντελούνται, αναλύονται ως συμβάντα γραμματισμού, ως δραστηριότητες δηλαδή που περιστρέφονται με αφορμή και γύρω από γραπτά κείμενα. Για την πραγματοποίηση της ανάλυσης καταρτίζεται ένα μεθοδολογικό εργαλείο (Ιντζίδης, 2019, Ιντζίδης & Ρήγας, 2022), το οποίο αντλεί στοιχεία από ποικίλες γλωσσολογικές θεωρίες και κλάδους, όπως η Συστημική Λειτουργική Γραμματική, η Κριτική Ανάλυση Λόγου, η Πραγματολογία και η Γνωσιακή Γλωσσολογία. Στο κύριο μέρος της εργασίας, όψεις του εργαλείου εφαρμόζονται αρχικά στο πρωτότυπο κείμενο που ελέγχεται ως παραπληροφορητικό, έπειτα στο κείμενο που του ασκεί τον έλεγχο και τέλος στα σχόλια του κοινού που έπονται των δύο προαναφερθέντων κειμένων. Ο πρώτιστος στόχος της εργασίας είναι η αναλυτική περιγραφή των διαδικασιών αναπαράστασης της πραγματικότητας μέσω της γλώσσας και των άλλων σημειωτικών πόρων (εικόνες, βίντεο, μουσική) που αξιοποιούν οι άνθρωποι, όταν σχεδιάζουν τα νοήματά τους στο πολυτροπικό συνεχές προφορικού - γραπτού λόγου. Ο απώτερος στόχος της είναι να καταστήσει τους αναγνώστες ειδησεογραφικών κειμένων (γραπτών ή/και προφορικών) συνειδητούς γνώστες αυτών των διαδικασιών και να τους επιτρέψει να τις αναγνωρίζουν και οι ίδιοι στα ποικίλα ειδησεογραφικά (ενίοτε παραπληροφορητικά) κείμενα, στα οποία εκτίθενται καθημερινά.The thesis entitled Literacy and Disinformation investigates the construction and negotiation of meaning in news articles concerning the harmful effects of the vaccines against Covid - 19 that can be regarded as disinformative. These articles are examined in conjunction with texts that check the facts mentioned, as well as reader comments on them. After an overview of the research literature on media discourse, the thesis focuses on the concepts of disinformation, fake news and myths, prevailing in today's post-truth society. The communicative interactions that take place are analyzed as literacy events, that is as activities that contain and revolve around written texts. A methodological tool, which draws inspiration from various linguistic theories and disciplines, such as Systemic Functional Grammar, Critical Discourse Analysis, Pragmatics and Cognitive Linguistics, is constructed and proposed for the analysis (Intzidis, 2019, Intzidis & Rigas, 2022). In the main body of the work, aspects of the tool are applied firstly to the text that is regarded as disinformative, then to the text that conducts the fact - checking and finally to the social media comments of the audience that follow the aforementioned texts. The primary goal of the thesis is the detailed description of the processes through which language and other semiotic resources (images, video, music) represent reality, when they are used by writers who design their meanings in the multimodal continuum of oral-written discourse. Its ultimate goal is to make the readers of news texts (written and / or oral) more aware of these processes and to enable their identification in the various (disinformative or not) news texts to which they are exposed on a daily basis

Diminished social motivation in early psychosis is associated with polygenic liability for low vitamin D

Insufficiency of vitamin D levels often occur in individuals with schizophrenia and first-episode psychosis (FEP). However, it is unknown whether this represents a biological predisposition, or it is essentially driven by illness-related alterations in lifestyle habits. Lower vitamin D has also been associated with adverse neurodevelopmental outcomes and predominant negative psychotic symptoms. This study aimed to investigate the contribution of polygenic risk score for circulating 25-hydroxyvitamin D concentration (PRS-vitD) to symptom presentation among individuals with FEP enrolled in the Athens First-Episode Psychosis Research Study (AthensFEP n = 205) and the Psychosis Incident Cohort Outcome Study (PICOS n = 123). The severity of psychopathology was evaluated using the Positive and Negative Syndrome Scale at baseline and follow-up assessments (AthensFEP: 4-weeks follow-up, PICOS: 1-year follow-up). Premorbid intelligence and adjustment domains were also examined as proxy measures of neurodevelopmental deviations. An inverse association between PRS-vitD and severity of negative symptoms, in particular lack of social motivation, was detected in the AthensFEP at baseline (adjusted R2 = 0.04, p < 0.001) and follow-up (adjusted R2 = 0.03, p < 0.01). The above observation was independently validated in PICOS at follow-up (adjusted R2 = 0.06, p < 0.01). No evidence emerged for a relationship between PRS-vitD and premorbid measures of intelligence and adjustment, likely not supporting an impact of lower PRS-vitD on developmental trajectories related to psychotic illness. These findings suggest that polygenic vulnerability to reduced vitamin D impairs motivation and social interaction in individuals with FEP, thereby interventions that encourage outdoor activities and social engagement in this patient group might attenuate enduring negative symptoms

The Role of Eye Gaze in Security and Privacy Applications: Survey and Future HCI Research Directions

For the past 20 years, researchers have investigated the use of eye tracking in security applications. We present a holistic view on gaze-based security applications. In particular, we canvassed the literature and classify the utility of gaze in security applications into a) authentication, b) privacy protection, and c) gaze monitoring during security critical tasks. This allows us to chart several research directions, most importantly 1) conducting field studies of implicit and explicit gaze-based authentication due to recent advances in eye tracking, 2) research on gaze-based privacy protection and gaze monitoring in security critical tasks which are under-investigated yet very promising areas, and 3) understanding the privacy implications of pervasive eye tracking. We discuss the most promising opportunities and most pressing challenges of eye tracking for security that will shape research in gaze-based security applications for the next decade

Mixed Models as a Tool for Comparing Groups of Time Series in Plant Sciences

Plants adapt to continual changes in environmental conditions throughout their life spans. High-throughput phenotyping methods have been developed to noninvasively monitor the physiological responses to abiotic/biotic stresses on a scale spanning a long time, covering most of the vegetative and reproductive stages. However, some of the physiological events comprise almost immediate and very fast responses towards the changing environment which might be overlooked in long-term observations. Additionally, there are certain technical difficulties and restrictions in analyzing phenotyping data, especially when dealing with repeated measurements. In this study, a method for comparing means at different time points using generalized linear mixed models combined with classical time series models is presented. As an example, we use multiple chlorophyll time series measurements from different genotypes. The use of additional time series models as random effects is essential as the residuals of the initial mixed model may contain autocorrelations that bias the result. The nature of mixed models offers a viable solution as these can incorporate time series models for residuals as random effects. The results from analyzing chlorophyll content time series show that the autocorrelation is successfully eliminated from the residuals and incorporated into the final model. This allows the use of statistical inference