Quantifying the predictability of visual scanpaths using active information storage

Entropy-based measures are an important tool for studying human gaze behavior under various conditions. In particular, gaze transition entropy (GTE) is a popular method to quantify the predictability of fixation transitions. However, GTE does not account for temporal dependencies beyond two consecutive fixations and may thus underestimate a scanpath's actual predictability. Instead, we propose to quantify scanpath predictability by estimating the active information storage (AIS), which can account for dependencies spanning multiple fixations. AIS is calculated as the mutual information between a processes' multivariate past state and its next value. It is thus able to measure how much information a sequence of past fixations provides about the next fixation, hence covering a longer temporal horizon. Applying the proposed approach, we were able to distinguish between induced observer states based on estimated AIS, providing first evidence that AIS may be used in the inference of user states to improve human-machine interaction.Comment: 19 pages, 3 figure

Biophilic interventions in crew quarters for deep space transit habitats to improve cognitive and physiological health measures

While the concept of biophilic design has been around for many decades, new methods for studying and quantifying the effects of biophilic design in virtual reality present unique opportunities for interior designers and architects, while exploring design concepts for spacecrafts and space habitats. When a person experiences a space with biophilic design, it can result in both cognitive and physiological benefits. There is a critical need to not only integrate biophilia into the design of the interiors of spacecraft but to study the benefits of this as well. The purpose of this study was to assess if the integration of biophilic design in a virtual simulation of personal crew quarters on the International Space Station (ISS) can help improve emotions and feelings while also improving cognitive responses in individuals. The specific aims of the study include the following: a) Determine if virtual biophilic crew quarters result in an improvement to overall feelings and emotions when compared to the current design; b) Determine if virtual crew quarters designed with the integration of biophilic design result in an improvement in cognitive load when compared to the current design; c) Determine if virtual crew quarters designed with the integration of biophilic design result in an improvement in satisfaction and intent to spend more time in the space when compared to the current design; d) Determine if virtual crew quarters designed with the integration of biophilic design result in an improvement in cognitive responses when compared to the current design. The participants answered survey questions to assess specific measures related to feelings and emotions, task load, and cognitive responses and heart rate and pupil dilation were also measured. The study found that there were significant differences in feelings and emotions, pupil dilation, performance, and effort, and moderate to strong correlations between satisfaction with the space and intention to spend more time in the space. This study has important implications for the design of space habitats to help improve the health and wellbeing of astronauts and space travelers

Studying Eye Movements as a Basis for Measuring Cognitive Load

Users' cognitive load while interacting with a system is a valuable metric for evaluations in HCI. We encourage the analysis of eye movements as an unobtrusive and widely available way to measure cognitive load. In this paper, we report initial findings from a user study with 26 participants working on three visual search tasks that represent different levels of difficulty. Also, we linearly increased the cognitive demand while solving the tasks. This allowed us to analyze the reaction of individual eye movements to different levels of task difficulty. Our results show how pupil dilation, blink rate, and the number of fixations and saccades per second individually react to changes in cognitive activity. We discuss how these measurements could be combined in future work to allow for a comprehensive investigation of cognitive load in interactive settings.publishe