50 research outputs found
Gaze Distribution Analysis and Saliency Prediction Across Age Groups
Knowledge of the human visual system helps to develop better computational
models of visual attention. State-of-the-art models have been developed to
mimic the visual attention system of young adults that, however, largely ignore
the variations that occur with age. In this paper, we investigated how visual
scene processing changes with age and we propose an age-adapted framework that
helps to develop a computational model that can predict saliency across
different age groups. Our analysis uncovers how the explorativeness of an
observer varies with age, how well saliency maps of an age group agree with
fixation points of observers from the same or different age groups, and how age
influences the center bias. We analyzed the eye movement behavior of 82
observers belonging to four age groups while they explored visual scenes.
Explorativeness was quantified in terms of the entropy of a saliency map, and
area under the curve (AUC) metrics was used to quantify the agreement analysis
and the center bias. These results were used to develop age adapted saliency
models. Our results suggest that the proposed age-adapted saliency model
outperforms existing saliency models in predicting the regions of interest
across age groups
Visual Attention Saccadic Models Learn to Emulate Gaze Patterns From Childhood to Adulthood
International audienceHow people look at visual information reveals fundamental information about themselves, their interests and their state of mind. While previous visual attention models output static 2-dimensional saliency maps, saccadic models aim to predict not only where observers look at but also how they move their eyes to explore the scene. In this paper, we demonstrate that saccadic models are a flexible framework that can be tailored to emulate observer's viewing tendencies. More specifically, we use fixation data from 101 observers split into 5 age groups (adults, 8-10 y.o., 6-8 y.o., 4-6 y.o. and 2 y.o.) to train our saccadic model for different stages of the development of human visual system. We show that the joint distribution of saccade amplitude and orientation is a visual signature specific to each age group, and can be used to generate age-dependent scanpaths. Our age-dependent saccadic model does not only output human-like, age-specific visual scanpaths, but also significantly outperforms other state-of-the-art saliency models. We demonstrate that the computational modelling of visual attention, through the use of saccadic model, can be efficiently adapted to emulate the gaze behavior of a specific group of observers
Displaced vertices from pseudo-Dirac dark matter
Displaced vertices are relatively unusual signatures for dark matter searches at the LHC. We revisit the model of pseudo-Dirac dark matter (pDDM), which can accommodate the correct relic density, evade direct detection constraints, and generically provide observable collider signatures in the form of displaced vertices. We use this model as a benchmark to illustrate the general techniques involved in the analysis, the complementarity between monojet and displaced vertex searches, and provide a comprehensive study of the current bounds and prospective reach