Oculomotor Activity Research Articles

Microsaccade rate activity during the preparation of pro- and antisaccades.

Microsaccades belong to the category of fixational micromovements and may be crucial for image stability on the retina. Eye movement paradigms typically requirefixational control, but this does not eliminate all oculomotor activity. The antisaccade task requires a planned eye movement in the direction opposite of an onset, allowing separation of planning and execution. We build on previous studies of microsaccades in the antisaccade task using a combination of fixed and mixed pro- and antisaccade blocks. We hypothesized that microsaccade rates may be reduced prior to the execution of antisaccades as compared with regular saccades (prosaccades). In two experiments, we measured microsaccades in four conditions across three trial blocks: one block each of fixed prosaccade and antisaccade trials, and a mixed block where both saccade types were randomized. We anticipated that microsaccade rates would be higher prior to antisaccades than prosaccades due to the need to preemptively suppress reflexive saccades during antisaccade generation. In Experiment 1, with monocular eye tracking, there was an interaction between the effects of saccade and block type on microsaccade rates, suggesting lower rates on antisaccade trials, but only within mixed blocks. In Experiment 2, eye tracking was binocular, revealing suppressed microsaccade rates on antisaccade trials. A cluster permutation analysis of the microsaccade rate over the course of a trial did not reveal any particular critical time for this difference in microsaccade rates. Our findings suggest that microsaccade rates reflect the degree of suppression of the oculomotor system during the antisaccade task.

Айтрекинг-исследование визуального внимания детей с нарушением слуха в ситуации обучения

<p>Potential mechanisms underlying atypical joint attention that impede effective learning are analyzed using the example of the consequences of hearing impairment. A sample of preschool children with hearing impairment after cochlear implantation (sensorineural hearing loss, ICD-10 class H90) was studied. For the study, an experimental situation was created that would allow tracing the learning difficulties in children with hearing impairments associated with the skills of joint attention. In the course of completing a training task jointly with an adult in children with hearing impairment, eye movements were recorded with a portable tracker in the form of Pupil Headset glasses. In the course of the study, it was possible to identify and visualize markers of oculomotor activity that impede their effective learning: distribution of visual attention over a wide area of the visual field, not in a focused mode; in the trajectory of eye movements and the position of fixations, there is a preference for non-social signals, non-target objects, difficulties in switching attention from one object to another. The main manifestation of joint attention deficit in preschoolers with hearing impairment is a decrease in the volume and time of stable maintenance of synchronicity of perception in the learning process. The parameters of oculomotor activity can serve as an indicator of the ability of a child with a hearing impairment to maintain attention to the sample form and a diagnostic indicator of the possible number of errors in the learning process. Such indicators are the duration and number of fixations. The role of multimodal means of maintaining visual attention to the sample in the process of teaching children with hearing impairment is shown. It was revealed that the attention of a child with hearing impairment to the face of an adult is part of the joint attention to the object, which improves the effectiveness of learning and is associated with a longer visual attention to the object (teaching pattern).</p>

The influence of the stimulus category on the characteristics of eye movements in visual search

Introduction. The speed and efficiency of visual search are important characteristics of the activities of a significant range of specialists working with visual information. Specialists have carefully studied the features of visual search from the point of view of cognitive psychology and in connection with the modeling of oculomotor activity. It has been shown that its effectiveness and the parameters of search eye movements are influenced by both stimulation factors and some cognitive factors (features of the subject's preset, the influence of previous search stages, etc.). We assume that the search features are also related to how well a person represents the desired stimulus: whether it belongs to a familiar semantic category, how accurate and unambiguous its visual representation is.
 The study aims to explore the relationship between the parameters of eye movements in visual search and the features of the mental representation of the target object.
 Materials and methods. We have created sets of stimuli belonging to different semantic categories, characterized by different accuracy of mental representations, but having similar sensory qualities. Each object (both the target stimulus and the distractor) in the search field was a black circle on a white background with four black segments inside. The segments formed one of three configurations: a) a face; b) a Roman numeral; c) a random configuration. The study participants were asked to find in a matrix of 84 objects a specific target stimulus belonging to one of the three specified categories. The scientists recorded the participant's eye movements during the search.
 Results. The results of the study generally confirmed the hypothesis about the relationship of search characteristics with the category of the target object. The smallest number of errors, the minimum duration of fixation and the maximum amplitude of saccades characterized the search for Roman numerals — objects with a well-formed and well-defined visual representation. The most difficult, as expected, was the search for objects representing random configurations of segments.
 Limitations. Since the study was largely exploratory in nature, the results obtained require clarification on a wider sample. It is possible that the characteristics of the search were influenced by such a factor not controlled in the study as the configuration of the lines, namely, the presence or absence of their intersections, which should be taken into account in further work.
 Conclusions. The better the visual representation of the target object is formed, the more successful its search is. In this case, eye movements are characterized by a shorter duration of fixation and a higher frequency of saccades of greater amplitude.
 Ethics. The study was conducted in compliance with the ethical principles set out in the Helsinki Declaration of the World Medical Association, all participants gave voluntary informed consent.

Do categorically distinct stressors alter the attention to visual food cues?

Stressor exposure affects food intake as well as the preference for high or low palatability foods, but little is known about how stressor types impact the visual attention to food images. We used eye tracking methodology in humans to determine if activation of the hypothalamus–pituitary-adrenal (HPA) axis and sympathetic nervous system is associated with changes in attention to food images as determined by measuring changes in oculomotor activity. Specifically, we tested two questions: 1) Do categorically distinct stressors alter aspects of visual attention to food images as determined by oculomotor activity (i.e., saccade latency, gaze duration, and saccade bouts)? 2) Do categorically distinct stressors differentially affect visual attention to food images of high or low palatability? A total of sixty participants were randomly divided into one of three test groups: controls, an anticipatory stressor group, or a reactive stressor group. We measured salivary cortisol and salivary alpha-amylase (sAA) before and after stressor exposure to confirm activation of the HPA axis and sympathetic nervous system, respectively. Following stressor exposure participants performed an eye-tracking test using a standardized food picture database (Food-pics). We analyzed saccade latency, gaze duration, and saccade bouts in balanced pairs of food and non-food images. Salivary cortisol was elevated by both stressors, although the elevation in salivary cortisol to the reactive stressor was driven by women only. sAA was elevated only by the anticipatory stressor. There were main effects of image type for all three eye-tracking variables, with initial saccades of shorter latency to food images and longer gaze duration and more saccade bouts with food images. Participants exposed to the reactive stressor reduced gaze duration on food images relative to controls, and this affect was not linked to palatability or salivary cortisol levels. We conclude that the reactive stressor decreased time spent looking at food, but not non-food, images. These data are partly consistent with the idea that reactive stressors reduce attention to non-critical visual signals.

Inferring visual space from ultra-fine extra-retinal knowledge of gaze position

It has long been debated how humans resolve fine details and perceive a stable visual world despite the incessant fixational motion of their eyes. Current theories assume these processes to rely solely on the visual input to the retina, without contributions from motor and/or proprioceptive sources. Here we show that contrary to this widespread assumption, the visual system has access to high-resolution extra-retinal knowledge of fixational eye motion and uses it to deduce spatial relations. Building on recent advances in gaze-contingent display control, we created a spatial discrimination task in which the stimulus configuration was entirely determined by oculomotor activity. Our results show that humans correctly infer geometrical relations in the absence of spatial information on the retina and accurately combine high-resolution extraretinal monitoring of gaze displacement with retinal signals. These findings reveal a sensory-motor strategy for encoding space, in which fine oculomotor knowledge is used to interpret the fixational input to the retina.

Method of print exposure assessment: Application in psycholinguistics and adaptation for the Russian language

Exposure to print represents the amount of time one devotes to reading. Print exposure is an essential measure of individual differences in research on language processing: it affects word recognition, reading speed, reading comprehension, oculomotor activity during the reading etc. An objective tool to assess the level print exposure is demanded in psycholinguistics and neurolinguistics. There are subjective methods to estimate print exposure like reading diaries and questionnaires, but they are based on introspection which makes the estimation inaccurate and exaggerating. So an objective tool — Author Recognition Test is considered to be more effective. It was first developed for English by K. Stanovich and R. West, who suggested a design based on the signal detection theory. This test provides a relative measure reflecting individual differences in print exposure. The first English version of Author Recognition Test cannot be representative for other languages and cultures, so it has to be adapted — Chinese, Korean, Dutch, German versions have been developed recently. In this article we present the Russian version of Author Recognition Test. The test shows high reliability. Author Recognition Test score shows a significant correlation with vocabulary size, spelling skills, and text comprehension skill. To sum up, this study is the first to develop a Russian version of Author Recognition Test. We show that Russian native speakers’ level of print exposure measured by this tool is correlated to some offline reading-related tasks.

The specificity of forming strategies of the dyad adult-child with hearing impairment in the process of learning: eye tracking of double eye tracking technologies (duet)

The article is devoted to the application of dual eye tracking (DUET) eye tracking technology in the analysis of multimodal cooperation in the process of learning the child-adult dyad. The methodology is described and the double eye tracking (DUET) procedure was tested during the performance of a learning task in the adultchild dyad. Synchronous registration of the dyad's eye movements was carried out by two portable trackers in the form of Pupil Headset goggles. A comparative study of the synchrony of perceptual processes was carried out in a sample of preschoolers 4-6 years old: typically developing children and children with hearing impairment after cochlear implantation (with sensorineural hearing loss, ICD-10 class H90). An analysis of the ways in which the gaze of the adult-child dyad moves makes it possible to model the learning process as the emergence and dynamic transformation of an intersubjective connection between the perceptionaction systems of a child and an adult. Comparison of gaze patterns showed that contrasting groups of children use different perceptual strategies in the learning process: the specificity of eye movements of contrasting groups is manifested in the perceptual actions themselves and in the pattern of eye movements relative to fixations in relevant areas corresponding to the task. It was found that the oculomotor activity of an adult changes in the process of interaction with children of contrasting groups and is organized taking into account the specific features of the child's perceptual activity.

Возможные маркеры аддиктивного поведения при окулографическом исследовании

The process of digitalization, creating conditions for the formation of new types of addictions - digital addictions, has transformed the existing mechanisms for the dissemination of chemical forms of addictive behavior. Changes in the forms, methods and varieties of psychoactive substances (PS) and behavioral models actualize the need for a deep understanding of the causes of this phenomenon and the definition of markers for its manifestation. The complexity of the preventive diagnosis of addictive behavior raises the question of using new, fundamentally different mechanisms for obtaining information. The oculography (or eyetracking) method has the necessary qualities, which allows you to determine the hidden intentions of a person by analyzing his oculomotor activity. The purpose of the study is to determine the diagnostic capabilities of the eye-tracking method in identifying a tendency to addictive behavior. The study was conducted as part of a laboratory experiment using the Tobii Pro Spectrum eyetracker by demonstrating the stimulus material “search for words in the fieldword”. The experiment tested the hypothesis of confirming the experience of using drugs, tobacco-containing substances and alcohol among young people on the basis of the psychophysiological data obtained as a result of eye-tracking. As a result of the study, it was found that the subjects do not show statistically significant differences in the search for neutral and trigger stimuli in the «Alcoholism» group, but they notice and read neutral words in the «Drug addiction» group more often. The conducted experiment allows us to state that the oculography method has diagnostic capabilities in relation to identifying markers of addictive behavior in the group of drug use. The continuation of experimental research in this direction seems promising and in demand, since the use of the psychophysiological methodincreases the reliability of the data obtained, minimizes the factor of social desirability and optimizes the diagnostic procedure itself.

Pursuit Eye Movements in the Context of Speech Development in Children with ASD

RESEARCH OBJECTIVE: The main goal of the presented research was to assess the pursuit eye movement of five- and six-year-old children with ASD in the context of speech development.
 RESEARCH PROBLEM AND METHODS: The research concerns the oculomotor activity of children with ASD in the situation of tracking slowly moving objects. The research questions refers to the relationships between the tracking movements and the dynamics of the speech development of the research participants, and to their current abilities in this area. The eye tracking method was used in the research.
 THE PROCESS OF ARGUMENTATION: We presented the basic information about the vision process, with particular emphasis on the role of the pursuit eye movement. We also described the research on the importance of eye movement in the process of acquiring communication skills, building social relationships and effective functioning.
 RESEARCH RESULTS: The obtained results indicate the correlation between the independent variable (the pattern of smooth pursuit presented by the children taking part in the research), and the dynamics of disorder development and the level of speech development in the children with reference to the analyses of other authors.
 CONCLUSIONS, INNOVATIONS AND RECOMMENDATIONS: The conducted analyses revealed strong and moderate correlations between the variables and made it possible for the author to confirm the main hypothesis that the eye movements while tracking slow-moving objects in all directions are characterized by variability related to the dynamics of speech development in early childhood and the current abnormalities in this area among the research participants. The obtained results indicate the necessity to start vision training in children with ASD as early as possible.

Beyond alpha-band: The neural correlate of creative thinking

The compound nature of creativity entails the interplay of multiple cognitive processes, making it difficult to attribute creativity to a single neural signature. Divergent thinking paradigms, widely adopted to investigate creative production, have highlighted the key role of specific mental operations subserving creativity, such as inhibition of external stimuli, loose semantic associations, and mental imagery. Neurophysiological studies have typically shown a high alpha rhythm synchronization when individuals are engaged in creative ideation. Also, oculomotor activity and pupil diameter have been proposed as useful indicators of mental operations involved in such a thinking process. The goal of this study was to investigate whether beyond alpha-band activity other higher frequency bands, such as beta and gamma, may subserve divergent and convergent thinking and whether those could be associated with a different gaze bias and pupil response during ideas generation. Implementing a within-subjects design we collected behavioral measures, neural activity, gaze patterns, and pupil dilation while participants performed a revised version of the Alternative Uses Task, in which divergent thinking is contrasted to convergent thinking. As expected, participants took longer to generate creative ideas as compared to common ones. Interestingly, during divergent thinking participants displayed alpha synchronization along with beta and gamma desynchronization, more pronounced leftward gaze shift, and greater pupil dilation. During convergent thinking, an opposite pattern was observed: desynchronization in alpha and an increase in beta and gamma rhythm, along with a reduction of leftward gaze shift and greater pupil constriction. The present study uncovered specific neural dynamics and physiological patterns during idea generation, providing novel insight into the complex physiological signature of creative production.

Зрительное внимание у судебных экспертов и неэкспертов при восприятии и понимании поликодовых текстов

The article presents the results of experimental research into psychophysiological and psycholinguistic features of perception and understanding of multimodal texts with extremist content. The hypothesis verification was implemented by means of the analysis of the respondents' eye movement data, involving forensic linguists, practicing in anti-extremism cases, well-informed and not well-informed non-experts. Research methods were eye-tracking, quantitative data processing, structural-semantic analysis. The following statistically reliable data were obtained: experts and poorly informed respondents spent more time on the task and had some similarities in the parameters of oculomotor activity, in contrast to well-informed respondents, who quickly completed the task, avoiding detailed analysis of the stimulus; the respondents who answered "not sure", spent more time on the task, their viewing strategy was characterized by long frequent fixations in comparison to other groups; respondents who gave benchmark answers recognized the elements of the image with longer sparse fixations, within the least amount of time. The longest time of viewing, number and duration of fixations were revealed for the signs that have the largest number of connections with the surrounding components; one of the highest values of viewing time is recorded for incomprehensible signs. The results of the study demonstrate the psycholinguistic and psychophysiological features of perception and understanding multimodal texts in forensic linguists compared to professionals in other fields. Being applicable to fundamental research into information perception and processing, the results can also contribute to working out the methods of multimodal text forensic linguistic analysis.

«Цифровое поколение» осваивает чтение: влияние лингвистических параметров текста на глазодвигательные характеристики учеников 1–3-го классов

The level of reading literacy of the modern "digital generation" is an acute and significant topic. To explore this problem in dynamics it is necessary to objectively record the parameters of reading skills development in modern children. The article presents the results of an experimental study of the reading mechanism of elementary school students, performed using eye tracking. Fifty-three pupils in grades 1–3 of Moscow schools participated in the experiment, with real texts from Russian textbooks as stimulus material. Eye movements were recorded while reading texts from the screen, and after each text a comprehension question was asked. The results indicated a direct correlation between oculomotor characteristics and reading skill. From grade 1 to grade 3, the duration and number of fixations, amplitude duration, and reading time for both word and letter decreased, while the number of words with one or missing fixation increased. There was also a grade-independent effect of word length and word frequency factors on reading speed and oculomotor activity for students in all grades. Both factors had a significant effect on reading time, the average fixation duration was more sensitive to the frequency factor than to the word length factor, while word length alone influenced the first fixation duration.

Word frequency and text complexity: an eye-tracking study of young Russian readers

Although word frequency is often associated with the cognitive load on the reader and is widely used for automated text complexity assessment, to date, no eye-tracking data have been obtained on the effectiveness of this parameter for text complexity prediction for the Russian primary school readers. Besides, the optimal ways for taking into account the frequency of individual words to assess an entire text complexity have not yet been precisely determined. This article aims to fill these gaps. The study was conducted on a sample of 53 children of primary school age. As a stimulus material, we used 6 texts that differ in the classical Flesch readability formula and data on the frequency of words in texts. As sources of the frequency data, we used the common frequency dictionary based on the material of the Russian National Corpus and DetCorpus - the corpus of literature addressed to children. The speed of reading the text aloud in words per minute averaged over the grades was employed as a measure of the text complexity. The best predictive results of the relative reading time were obtained using the lemma frequency data from the DetCorpus. At the text level, the highest correlation with the reading speed was shown by the text coverage with a list of 5,000 most frequent words, while both sources of the lists - Russian National Corpus and DetCorpus - showed almost the same correlation values. For a more detailed analysis, we also calculated the correlation of the frequency parameters of specific word forms and lemmas with three parameters of oculomotor activity: the dwell time, fixations count, and the average duration of fixations. At the word-by-word level, the lemma frequency by DetCorpus demonstrated the highest correlation with the relative reading time. The results we obtained confirm the feasibility of using frequency data in the text complexity assessment task for primary school children and demonstrate the optimal ways to calculate frequency data.

Scene Viewing Characteristics: Oculomotor Activity of Children 4–6 Years of Age

Scene Viewing Characteristics: Oculomotor Activity of Children 4–6 Years of Age

Assessment of Mental Workload by Visual Motor Activity among Control Group and Patient Suffering from Depressive Disorder.

Major depressive disorder (MDD) is a mood state that is not usually associated with vision problems. Recent research has found that the inhibitory neurotransmitter GABA levels in the occipital brain have dropped. Aim. The aim of the research is to evaluate mental workload by single channel electroencephalogram (EEG) approach through visual-motor activity and comparison of parameter among depressive disorder patient and in control group. Method. Two tests of a visual-motor task similar to reflect drawings were performed in this study to compare the visual information processing of patients with depression to that of a placebo group. The current study looks into the accuracy of monitoring cognitive burden with single-channel portable EEG equipment. Results. The alteration of frontal brain movement in reaction to fluctuations in cognitive burden stages generated through various vasomotor function was examined. By applying a computerised oculomotor activity analogous to reflector image diagram, we found that the complexity of the path to be drawn was more important than the real time required accomplishing the job in determining perceived difficulty in depressive disorder patients. The overall perceived difficulty of the exercise is positively linked with EEG activity measured from the motor cortex region at the start of every experiment test. The average rating for task completion for depression patients and in control group observed and no statistical significance association reported between rating scale and time spent on each trial (p=1.43) for control group while the normalised perceived difficulty rating had 0.512, 0.623, and 0.821 correlations with the length of the pathway, the integer of inclination in the pathway, and the time spent to complete every experiment test, respectively (p < 0.0001) among depression patients. The findings imply that alterations in comparative cognitive burden levels during an oculomotor activity considerably modify frontal EEG spectrum. Conclusion. Patients with depression perceived the optical illusion in the arrays as weaker, resulting in a little bigger disparity than individuals who were not diagnosed with depression. This discovery provided light on the prospect of adopting a user-friendly mobile EEG technology to assess mental workload in everyday life.

Oculomotor Activity during Solution of Visual Cognitive Tasks in Different Time Conditions

Oculomotor Activity during Solution of Visual Cognitive Tasks in Different Time Conditions

АЙТРЕКИНГ ИССЛЕДОВАНИЯ ИСПОЛЬЗОВАНИЯ РАЗНЫХ ФОРМ ИНСТРУКЦИИ В ОБУЧЕНИИ ДЕТЕЙ С НАРУШЕНИЕМ СЛУХА

Background. It is analyzed how the method of eye movement registration can be used to study the learning processes of children with hearing impairment. On the basis of oculomotor activity data, diffi culties are identifi ed that impede the learning of children with hearing impairment, which contributes to the discovery of eff ective ways of learning. A separate research issue is the search for the eff ective use of diff erent forms of instruction. Objective. Eye-tracking study of learning diffi culties with diff erent forms of instruction (as diff erent forms of multimodal means of establishing joint attention). Sample. Th e study sample consisted of 15 preschool children with hearing impairment (sensoneural hearing loss, class H90 according to ICD-11), eight girls, seven boys, mean age 5.4±0.8. Methods. A task was used in the form of a correction test to fi ll in the fi gures (according to the Pieron-Ruser method). To understand diff erent forms of instruction in 4 series of the experiment, the combination of the speech form and the use of action in explaining the rule for fi lling in the fi gures varied. Th e main method is the method of eye movement registration using the PLabs portable tracker-the eye tracker. Results. Th e most important criterion for the eff ectiveness of diff erent forms of instruction is the time from the beginning of the presentation of the instruction to the fi rst fi xation on the target object and the duration of attention delay in non-target areas. With multimodal instruction, longer fi xations are observed in relevant areas and short fi xations in irrelevant areas, fi xations are more oft en and faster in relevant areas. With the transition to independent analysis, tasks at the beginning of fi xation in relevant and irrelevant areas become reduced in time and quantity, and then begin to take on an increasingly long character. Conclusion. A diff erent form of instruction allows you to restructure the perception of a child with a hearing impairment, focusing attention on the elements that are relevant to the task. Th e most eff ective is the simultaneous use of multimodal means of explaining instructions to attract and regulate attention.

An information model of the data structure and an experimental technique for improving the human-computer graphical interface

In the article, the authors describe the developed and tested methodology for conducting a computational experiment to study the effect of color solutions on the visual perception of a video frame by the viewer. The developed technique is designed to assess the subjective emotional reaction of the viewer that occurs at the final stage of the human visual system when perceiving visual information. The article describes methods of preparation of stimulus material, methods of conducting an experiment using a developed software module located on a network resource. The authors have developed a methodology for conducting an experiment with online testing, the information structure of the database, a questionnaire for collecting information, the form of testing by the subjects, algorithms for statistical processing of the results of the experiment. This study is based on the results of a series of experiments conducted using a software and hardware complex for fixing oculomotor activity - an eye tracker, which allows obtaining objective parametric data of a template for viewing stimulus material. The technique described in the article is an addition to the experimental study using the eytracking technology. The results of the experiment should be used in the development of textbooks on color correction, as well as in the design of control interface elements. The methodology is programmatically implemented and tested in the local network of Peter the Great St. Petersburg Polytechnic University. It is planned to finalize the Internet survey module and conduct a global experiment with subsequent statistical processing of the results.

Оценка состояния пилота по данным видеоокулографии и параметрам альфа-ритмов головного мозга путем моделирования его нейронной активности

The H.R. Wilson and J.D. Cowan model of human brain neural activity is considered, which connects the latent (non-measurable) parameters of external excitation with the brain neuronal activity parameters which are available for observation, with alpha rhythm frequencies being in use in this capacity. By means of computational experiments, revealed are the ranges of latent parameters, which ensure the occurrence of the Poincaré—Andronov—Hopf bifurcation (transforming the spiral sink to the spiral source equilibrium point with a limit cycle, or vice versa) that leads, in the first approximation, to the appearance of alpha rhythms. Relative changes of the latent parameters representing external excitation are estimated through the primary indices of oculomotor activity (gaze movement entropies and gaze fixation durations), which makes it possible to assess the pilot proximity to falling into a low efficiency state, including the real time mode.

Методические особенности оценки педофильного расстройства с применением айтрекера

The article presents the results of an original pilot study aimed at revealing peculiarities of oculomotor activity in persons with pedophilic disorder under conditions of specific erotic visual stimulation. 36 men were examined at the Laboratory of Forensic Sexology of the V.P. Serbsky National Medical Research Centre for Psychiatry and Narcology of the Ministry of Health of the Russian Federation. The study group consisted of the subjects diagnosed with pedophilia (28%), the control group included those tested without clinical signs of sexual preference disorder (72%). Oculomotor behavior was studied when viewing photographs of women and children in everyday settings. The results of the study revealed that subjects with pedophile disorder had peculiarities of oculomotor activity that differed from those in the normative sample. In particular, persons with pedophilia commit a greater number of fixations on the image of a child, and the total duration of fixations when viewing the image of a child is longer than in the control group. The findings suggest that fixation activity is significant in the evaluation of sexual preferences in the examined subjects.