Open Access
SeTA: semiautomatic tool for annotation of eye tracking images
(ACM, 2019) Larumbe Bergera, Andoni; Porta Cuéllar, Sonia; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Availability of large scale tagged datasets is a must in the field of deep learning applied to the eye tracking challenge. In this paper, the potential of Supervised-Descent-Method (SDM) as a semiautomatic labelling tool for eye tracking images is shown. The objective of the paper is to evidence how the human effort needed for manually labelling large eye tracking datasets can be radically reduced by the use of cascaded regressors. Different applications are provided in the fields of high and low resolution systems. An iris/pupil center labelling is shown as example for low resolution images while a pupil contour points detection is demonstrated in high resolution. In both cases manual annotation requirements are drastically reduced.
Open Access
Effects of a family-based lifestyle intervention plus supervised exercise training on abdominal fat depots in children with overweight or obesity: a secondary analysis of a nonrandomized clinical trial
(American Medical Association, 2022) Cadenas-Sánchez, Cristina; Cabeza Laguna, Rafael; Idoate, Fernando; Osés Recalde, Maddi; Medrano Echeverría, María; Villanueva Larre, Arantxa; Arenaza Etxeberría, Lide; Sanz Muñoz, Aritz; Ortega, Francisco B.; Ruiz, Jonatan R.; Labayen Goñi, Idoia; Ciencias de la Salud; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Institute of Smart Cities - ISC; Osasun Zientziak; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Importance Excess abdominal fat is a major determinant in the development of insulin resistance and other metabolic disorders. Increased visceral adipose tissue (VAT) seems to precede the development of insulin resistance and is therefore a prime target of childhood lifestyle interventions aimed at preventing diabetes. OBJECTIVES To examine the effect of added exercise to a family-based lifestyle intervention program designed to reduce VAT plus subcutaneous (ASAT), intermuscular (IMAAT), and pancreatic (PAT) adipose tissue in children with overweight or obesity and to explore the effect of changes in VAT on insulin resistance. DESIGN, SETTING, AND PARTICIPANTS This 2-group, parallel-design clinical trial was conducted in Vitoria-Gasteiz, Spain. A total of 116 children with overweight or obesity participated and were assigned to a 22-week family-based lifestyle program (control group [n = 57]) or the same program plus an exercise intervention (exercise group [n = 59]). Data were collected between September 1, 2014, and June 30, 2017, and imaging processing for fat depot assessments and data analysis were performed between May 1, 2019, and February 12, 2021. INTERVENTIONS The compared interventions consisted of a family-based lifestyle and psychoeducation program (two 90-minute sessions per month) and the same program plus supervised exercise (three 90-minute sessions per week). MAIN OUTCOMES AND MEASURES The primary outcome of this study was the change in VAT between baseline and 22 weeks as estimated by magnetic resonance imaging. The secondary outcomes were changes in ASAT, IMAAT, and PAT. The effect of changes in VAT area on insulin resistance was also recorded. RESULTS The 116 participants included in the analysis (62 girls [53.4%]) had a mean (SD) age of 10.6 (1.1) years, and 67 (57.8%) presented with obesity. Significantly greater reductions were recorded for the exercise group in terms of reduction in VAT (−18.1% vs −8.5% for the control group; P = .004), ASAT (−9.9% vs −3.0%; P = .001), and IMAAT (−6.0% vs −2.6%; P = .02) fat fractions compared with the control group. Changes in VAT explained 87.6% of the improvement seen in insulin resistance (β = −0.102 [95% CI, −0.230 to −0.002]). CONCLUSIONS AND RELEVANCE These findings suggest that the addition of exercise to a lifestyle intervention program substantially enhanced the positive effects on abdominal fat depots in children with overweight or obesity. In addition, the reduction in VAT seemed to largely mediate the improvement of insulin sensitivity. These results highlight the importance of including exercise as part of lifestyle therapies aimed at treating childhood obesity and preventing the development of type 2 diabetes.
Open Access
Low cost gaze estimation: knowledge-based solutions
(IEEE, 2020) Martinikorena Aranburu, Ion; Larumbe Bergera, Andoni; Ariz Galilea, Mikel; Porta Cuéllar, Sonia; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Eye tracking technology in low resolution scenarios is not a completely solved issue to date. The possibility of using eye tracking in a mobile gadget is a challenging objective that would permit to spread this technology to non-explored fields. In this paper, a knowledge based approach is presented to solve gaze estimation in low resolution settings. The understanding of the high resolution paradigm permits to propose alternative models to solve gaze estimation. In this manner, three models are presented: a geometrical model, an interpolation model and a compound model, as solutions for gaze estimation for remote low resolution systems. Since this work considers head position essential to improve gaze accuracy, a method for head pose estimation is also proposed. The methods are validated in an optimal framework, I2Head database, which combines head and gaze data. The experimental validation of the models demonstrates their sensitivity to image processing inaccuracies, critical in the case of the geometrical model. Static and extreme movement scenarios are analyzed showing the higher robustness of compound and geometrical models in the presence of user’s displacement. Accuracy values of about 3◦ have been obtained, increasing to values close to 5◦ in extreme displacement settings, results fully comparable with the state-of-the-art.
Open Access
Models for gaze tracking systems
(Hindawi Publishing Corporation, 2007) Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
One of the most confusing aspects that one meets when introducing oneself into gaze tracking technology is the wide variety, in terms of hardware equipment, of available systems that provide solutions to the same matter, that is, determining the point the subject is looking at. The calibration process permits generally adjusting nonintrusive trackers based on quite different hardware and image features to the subject. The negative aspect of this simple procedure is that it permits the system to work properly but at the expense of a lack of control over the intrinsic behavior of the tracker. The objective of the presented article is to overcome this obstacle to explore more deeply the elements of a video-oculographic system, that is, eye, camera, lighting, and so forth, from a purely mathematical and geometrical point of view. The main contribution is to find out the minimum number of hardware elements and image features that are needed to determine the point the subject is looking at. A model has been constructed based on pupil contour and multiple lighting, and successfully tested with real subjects. On the other hand, theoretical aspects of video-oculographic systems have been thoroughly reviewed in order to build a theoretical basis for further studies.
Open Access
Accurate pupil center detection in off-the-shelf eye tracking systems using convolutional neural networks
(MDPI, 2021) Larumbe Bergera, Andoni; Garde Lecumberri, Gonzalo; Porta Cuéllar, Sonia; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Remote eye tracking technology has suffered an increasing growth in recent years due to its applicability in many research areas. In this paper, a video-oculography method based on convolutional neural networks (CNNs) for pupil center detection over webcam images is proposed. As the first contribution of this work and in order to train the model, a pupil center manual labeling procedure of a facial landmark dataset has been performed. The model has been tested over both real and synthetic databases and outperforms state-of-the-art methods, achieving pupil center estimation errors below the size of a constricted pupil in more than 95% of the images, while reducing computing time by a 8 factor. Results show the importance of use high quality training data and well-known architectures to achieve an outstanding performance.
Open Access
Effects of time-restricted eating and resistance training on skeletal muscle tissue quantity, quality and function in postmenopausal women with overweight or obesity: a study protocol
(Elsevier, 2024-12-30) Alfaro-Magallanes, Víctor Manuel; Medrano Echeverría, María; Echarte Medina, Jon; Osés Recalde, Maddi; Izquierdo Rodríguez, Claudia; Concepción Álvarez, Mara de la Caridad; Galbete Jiménez, Arkaitz; Idoate, Fernando; Zugasti Murillo, Ana; Petrina Jáuregui, María Estrella; Goñi Gironés, María Elena; Ribelles, María Jesús; Amasene, María; Arenaza Etxeberría, Lide; Tejada Garrido, Clara Isabel; Elejalde, E.; Azcárate Jiménez, Unai Xabier; Ruiz Sarrias, Oskitz; Sayar-Beristain, Onintza; García-Ramos, Amador; Martínez Labari, Cristina; Armendáriz Brugos, Cristina; Villanueva Larre, Arantxa; Ruiz, Jonatan R.; Cabeza Laguna, Rafael; Labayen Goñi, Idoia; Ciencias de la Salud; Osasun Zientziak; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Background & aims: time-restricted eating (TRE) shows promise for weight loss and improving menopauserelated body composition and cardiometabolic health, but its effects on skeletal muscle tissue (SMT) in postmenopausal women are unknown. This study investigates the effects of three weight loss interventions over 12 weeks on SMT quantity, quality, function, and cardiometabolic health in postmenopausal women with overweight/obesity, with effects persistence evaluated at a 12-month follow-up. Methods and results: in this randomized controlled trial, 78 postmenopausal women (50–65 years; BMI 25–40 kg/m2; sedentary lifestyle; eating window ≥12 h/day; no severe metabolic impairments) will be recruited. Participants will be randomly assigned to one of three groups for 12 weeks: TRE, TRE + resistance training, or CR + resistance training. The TRE groups will reduce their eating window to 8 h and receive nutritional advice to adhere to a Mediterranean diet. The CR group will follow a personalized hypocaloric diet (− 500 kcal/day). Resistance training groups will perform supervised resistance training 3 times/week. Primary Outcome: Change in SMT quantity measured by MRI at baseline and after 12 weeks. Secondary Outcomes: intermuscular adipose tissue (IMAT), strength, power, body weight and composition, and cardiometabolic risk factors. Conclusion: this study will illustrate the effects of TRE and TRE combined with resistance exercise compared with the currently recommended obesity-lifestyle treatment on SMT quantity, quality, function, and cardiometabolic markers. The results will offer insights into dietary strategies to combat obesity and metabolic diseases without increasing sarcopenia risk in postmenopausal women, a sparsely studied and particularly affected population.
Open Access
Fisiopatología y técnicas de registro de los movimientos oculares
(Gobierno de Navarra, 2009) Gila Useros, Luis; Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
En el control de la motilidad ocular intervienen varios sistemas funcionales. Los reflejos vestíbulo-oculares y optocinéticos son respuestas automáticas para compensar los movimientos de la cabeza y del entorno visual y poder estabilizar la imagen retiniana sobre un determinado punto de fijación. Los movimientos sacádicos son rápidos desplazamientos de la fijación de un punto a otro del campo visual. Los movimientos de persecución lenta consisten en el seguimiento de estímulos móviles con la mirada. Finalmente, existen movimientos involuntarios de muy escasa amplitud que se producen durante el mantenimiento de la fijación. Cada modalidad funcional de movimiento depende de circuitos neuronales específicos que trabajan coordinadamente para codificar la contracción de los músculos oculomotores correspondiente a la posición adecuada en cada momento. Estos sistemas neuronales pueden verse alterados por múltiples procesos neurológicos de diferente naturaleza y localización dando lugar a una variada gama de trastornos oculomotores. Se revisan los aspectos más destacados de la fisiopatología y de los sistemas de registro de los movimientos oculares.
Open Access
Attention to online channels across the path to purchase: an eye-tracking study
(Elsevier, 2019) Cortiñas Ugalde, Mónica; Cabeza Laguna, Rafael; Chocarro Eguaras, Raquel; Villanueva Larre, Arantxa; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Enpresen Kudeaketa; Institute for Advanced Research in Business and Economics - INARBE; Ingeniería Eléctrica, Electrónica y de Comunicación; Gestión de Empresas
Currently, consumers display what is known as omnichannel behavior: the combined use of digital and physical channels providing them with multiple points of contact with firms. We combine the stimulus-organism-response (S-O-R) model and visual attention theory to study how customers’ attention to digital channels varies across different purchasing tasks. We use eye-tracking techniques to observe attention in an experimental setting. The experimental design is composed of four purchasing tasks in four different product categories and measures the attention to the website and time spent on each task in addition to several control variables. The results show that shoppers attend to more areas of the website for purposes of website exploration than for performing purchase tasks. The most complex and time-consuming task for shoppers is the assessment of purchase options. The actual purchase and post-purchase tasks require less time and the inspection of fewer areas of interest. Personal involvement also plays a role in determining these patterns by increasing attention to the product area.
Open Access
Development of a prediction protocol for the screening of metabolic associated fatty liver disease in children with overweight or obesity
(Wiley, 2022) Osés Recalde, Maddi; Cadenas-Sánchez, Cristina; Medrano Echeverría, María; Galbete Jiménez, Arkaitz; Miranda Ferrúa, Emiliano; Ruiz, Jonatan R.; Sánchez-Valverde, Félix; Ortega, Francisco B.; Cabeza Laguna, Rafael; Villanueva Larre, Arantxa; Idoate, Fernando; Labayen Goñi, Idoia; Osasun Zientziak; Institute of Smart Cities - ISC; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Ciencias de la Salud; Gobierno de Navarra / Nafarroako Gobernua
Background: the early detection and management of children with metabolic associ-ated fatty liver disease (MAFLD) is challenging. Objective: to develop a non-invasive and accurate prediction protocol for the identi-fication of MAFLD among children with overweight/obesity candidates to confirma-tory diagnosis. Methods: a total of 115 children aged 8–12 years with overweight/obesity, rec-ruited at a primary care, were enrolled in this cross-sectional study. The external vali-dation was performed using a cohort of children with overweight/obesity (N=46)aged 8.5–14.0 years. MAFLD (≥5.5% hepatic fat) was diagnosed by magnetic reso-nance imaging (MRI). Fasting blood biochemical parameters were measured, and25 candidates’ single nucleotide polymorphisms (SNPs) were determined. Variablespotentially associated with the presence of MAFLD were included in a multivariatelogistic regression. Results: children with MAFLD (36%) showed higher plasma triglycerides (TG),insulin, homeostasis model assessment ofinsulin resistance (HOMA-IR), alanineaminotransferase (ALT), aspartate transaminase (AST), glutamyl-transferase (GGT)and ferritin (p< 0.05). The distribution of the risk-alleles of PPARGrs13081389, PPARGrs1801282, HFErs1800562 and PNLPLA3rs4823173 was significantly different between children with and without MAFLD (p<0.05). Threebiochemical- and/or SNPs-based predictive models were developed, showingstrong discriminatory capacity (AUC-ROC: 0.708–0.888) but limited diagnosticperformance (sensitivity 67%–82% and specificity 63%–69%). A prediction proto-col with elevated sensitivity (72%) and specificity (84%) based on two consecutive steps was developed. The external validation showed similar results: sensitivity of 70% and specificity of 85%. Conclusions: the HEPAKID prediction protocol is an accurate, easy to implant, minimally invasive and low economic cost tool useful for the early identification and management of paediatric MAFLD in primary care.
Open Access
Evaluation of accurate eye corner detection methods for gaze estimation
(Bern Open Publishing, 2014) Bengoechea Irañeta, José Javier; Cerrolaza Martínez, Juan José; Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Accurate detection of iris center and eye corners appears to be a promising approach for low cost gaze estimation. In this paper we propose novel eye inner corner detection methods. Appearance and feature based segmentation approaches are suggested. All these methods are exhaustively tested on a realistic dataset containing images of subjects gazing at different points on a screen. We have demonstrated that a method based on a neural network presents the best performance even in light changing scenarios. In addition to this method, algorithms based on AAM and Harris corner detector present better accuracies than recent high performance face points tracking methods such as Intraface.