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1.
Vestn Oftalmol ; 136(5): 142-148, 2020.
Artigo em Russo | MEDLINE | ID: mdl-33056976

RESUMO

Vertical strabismus caused by hyperfunction of the inferior oblique muscle is a common oculomotor disorder. It is found in one third of all patients with strabismus, and in 70% of cases it is combined with esotropia. To date, there is no single approach to determining the degree of hyperfunction of the inferior oblique muscle, and the most common classifications are very subjective and inaccurate. Thus, in connection with the need to understand the severity of the disease, as well as to determine the tactics of treatment and prognosis of the surgical outcomes, it is necessary to standartize the classification of this pathology. The mechanism of action of the inferior oblique muscles of the eye is very complex and depends on the position of the eyeball at the time of their contraction. In addition to horizontal and vertical movements, they provide torsional movement. Any impairment of these muscles leads to the development of not only vertical strabismus, but excyclotropia that reduces the effectiveness of strabismus treatment. To identify all the symptoms associated with hyperfunction of the inferior oblique muscle, taking into account the peculiarities of its triple action, it is necessary to conduct a thorough diagnostic study.


Assuntos
Estrabismo , Movimentos Oculares , Humanos , Músculos Oculomotores/cirurgia , Estrabismo/diagnóstico , Estrabismo/etiologia , Estrabismo/cirurgia
2.
Nat Commun ; 11(1): 4553, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917902

RESUMO

Eye tracking has been widely used for decades in vision research, language and usability. However, most prior research has focused on large desktop displays using specialized eye trackers that are expensive and cannot scale. Little is known about eye movement behavior on phones, despite their pervasiveness and large amount of time spent. We leverage machine learning to demonstrate accurate smartphone-based eye tracking without any additional hardware. We show that the accuracy of our method is comparable to state-of-the-art mobile eye trackers that are 100x more expensive. Using data from over 100 opted-in users, we replicate key findings from previous eye movement research on oculomotor tasks and saliency analyses during natural image viewing. In addition, we demonstrate the utility of smartphone-based gaze for detecting reading comprehension difficulty. Our results show the potential for scaling eye movement research by orders-of-magnitude to thousands of participants (with explicit consent), enabling advances in vision research, accessibility and healthcare.


Assuntos
Confiabilidade dos Dados , Medições dos Movimentos Oculares , Movimentos Oculares , Smartphone , Adolescente , Adulto , Compreensão , Feminino , Fixação Ocular , Humanos , Masculino , Pessoa de Meia-Idade , Leitura , Visão Ocular , Percepção Visual , Adulto Jovem
3.
PLoS One ; 15(8): e0237854, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853262

RESUMO

Drug-induced long QT syndrome (diLQTS), characterized by a prolongation of the QT-interval on the electrocardiogram (ECG), is a serious adverse drug reaction that can cause the life-threatening arrhythmia Torsade de Points (TdP). Self-monitoring for diLQTS could therefore save lives, but detecting it on the ECG is difficult, particularly at high and low heart rates. In this paper, we evaluate whether using a pseudo-colouring visualisation technique and changing the coordinate system (Cartesian vs. Polar) can support lay people in identifying QT-prolongation at varying heart rates. Four visualisation techniques were evaluated using a counterbalanced repeated measures design including Cartesian no-colouring, Cartesian pseudo-colouring, Polar no-colouring and Polar pseudo-colouring. We used a multi-reader, multi-case (MRMC) receiver operating characteristic (ROC) study design within a psychophysical paradigm, along with eye-tracking technology. Forty-three lay participants read forty ECGs (TdP risk n = 20, no risk n = 20), classifying each QT-interval as normal/abnormal, and rating their confidence on a 6-point scale. The results show that introducing pseudo-colouring to the ECG significantly increased accurate detection of QT-interval prolongation regardless of heart rate, T-wave morphology and coordinate system. Pseudo-colour also helped to reduce reaction times and increased satisfaction when reading the ECGs. Eye movement analysis indicated that pseudo-colour helped to focus visual attention on the areas of the ECG crucial to detecting QT-prolongation. The study indicates that pseudo-colouring enables lay people to visually identify drug-induced QT-prolongation regardless of heart rate, with implications for the more rapid identification and management of diLQTS.


Assuntos
Eletrocardiografia , Frequência Cardíaca , Síndrome do QT Longo/diagnóstico por imagem , Síndrome do QT Longo/fisiopatologia , Adulto , Cor , Movimentos Oculares/fisiologia , Feminino , Fixação Ocular/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação Pessoal , Estimulação Luminosa , Psicofísica , Curva ROC , Tempo de Reação , Fatores de Risco , Sensibilidade e Especificidade , Adulto Jovem
4.
PLoS One ; 15(8): e0237346, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790721

RESUMO

PURPOSE: We investigated how the abnormalities of fixation eye movements (FEMs) of the amblyopic eye were linked with treatment outcomes following part-time patching therapy in children with amblyopia. METHODS: We recruited 53 patients, with at least 12 months of patching, and measured FEMs at the end of treatment. Subjects were classified based on FEM waveforms (those without nystagmus = 21, those with nystagmus without fusion maldevelopment nystagmus (FMN) = 21, and those with FMN = 11) and based on clinical type of amblyopia (anisometropic = 18, strabismic = 6, and mixed = 29). The treatment outcomes such as duration of treatment of receiving part-time patching therapy, visual acuity and stereo-acuity deficits at the end of treatment were determined. Bivariate contour ellipse area (BCEA), fast (fixational saccade/quick phases), and slow (inter-saccadic drifts/slow phases) FEMs of the fellow and amblyopic eye were analyzed. RESULTS: Anisometropic group had less residual amblyopia (0.23±0.19logMAR acuity) compared to strabismic/mixed (0.36±0.26) groups (p = 0.007). Treatment duration in patients without nystagmus was lower (12.6±9.5months) compared to nystagmus without FMN (25.6±23.2) and FMN (29.5±20.4) groups (p = 0.006). Patients without nystagmus had better stereopsis at the end of treatment (2.3±0.84logarcsecs) compared to nystagmus without FMN (2.6±0.84) group (p = 0.003). The majority of patients with FMN (8/11) had absent stereopsis. BCEA of the amblyopic eye was higher in patients with greater residual visual acuity deficits in patients without nystagmus. No such association was seen in Nystagmus no FMN and FMN groups. Increased amplitude of fast FEMs, increased eye position variance and eye velocity of slow FEMs were seen in patients who had received longer duration of part time patching therapy and in those with greater residual amblyopia, and poor stereopsis at the end of treatment. CONCLUSIONS: Assessment of FEM waveforms and fast and slow FEM characteristics are important measures while describing fixation instability in amblyopia. Several FEM abnormalities were associated with stereo-acuity and visual acuity deficits and treatment duration in patients with amblyopia treated with part time patching therapy.


Assuntos
Ambliopia/complicações , Ambliopia/terapia , Nistagmo Patológico/complicações , Ambliopia/fisiopatologia , Criança , Pré-Escolar , Medições dos Movimentos Oculares , Movimentos Oculares , Humanos , Lactente , Nistagmo Patológico/fisiopatologia , Estudos Retrospectivos , Resultado do Tratamento
5.
Nat Commun ; 11(1): 3341, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620746

RESUMO

The oculomotor system keeps the eyes steady in expectation of visual events. Here, recording microsaccades while people performed a tactile, frequency discrimination task enabled us to test whether the oculomotor system shows an analogous preparatory response for unrelated tactile events. We manipulated the temporal predictability of tactile targets using tactile cues, which preceded the target by either constant (high predictability) or variable (low predictability) time intervals. We find that microsaccades are inhibited prior to tactile targets and more so for constant than variable intervals, revealing a tight crossmodal link between tactile temporal expectation and oculomotor action. These findings portray oculomotor freezing as a marker of crossmodal temporal expectation. Moreover, microsaccades occurring around the tactile target presentation are associated with reduced task performance, suggesting that oculomotor freezing mitigates potential detrimental, concomitant effects of microsaccades and revealing a crossmodal coupling between tactile perception and oculomotor action.


Assuntos
Movimentos Oculares/fisiologia , Desempenho Psicomotor/fisiologia , Percepção do Tempo/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Músculos Oculomotores/inervação , Músculos Oculomotores/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia , Movimentos Sacádicos/fisiologia , Adulto Jovem
6.
Nat Commun ; 11(1): 3524, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32665559

RESUMO

Eye movements are inhibited prior to the onset of temporally-predictable visual targets. This oculomotor inhibition effect could be considered a marker for the formation of temporal expectations and the allocation of temporal attention in the visual domain. Here we show that eye movements are also inhibited before predictable auditory targets. In two experiments, we manipulate the period between a cue and an auditory target to be either predictable or unpredictable. The findings show that although there is no perceptual gain from avoiding gaze-shifts in this procedure, saccades and blinks are inhibited prior to predictable relative to unpredictable auditory targets. These findings show that oculomotor inhibition occurs prior to auditory targets. This link between auditory expectation and oculomotor behavior reveals a multimodal perception action coupling, which has a central role in temporal expectations.


Assuntos
Atenção/fisiologia , Movimentos Oculares/fisiologia , Músculos Oculomotores/fisiologia , Adulto , Análise de Variância , Feminino , Humanos , Tempo de Reação/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
7.
Proc Natl Acad Sci U S A ; 117(31): 18799-18809, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32680968

RESUMO

We try to deploy the retinal fovea to optimally scrutinize an object of interest by directing our eyes to it. The horizontal and vertical components of eye positions acquired by goal-directed saccades are determined by the object's location. However, the eccentric eye positions also involve a torsional component, which according to Donder's law is fully determined by the two-dimensional (2D) eye position acquired. According to von Helmholtz, knowledge of the amount of torsion provided by Listing's law, an extension of Donder's law, alleviates the perceptual interpretation of the image tilt that changes with 2D eye position, a view supported by psychophysical experiments he pioneered. We address the question of where and how Listing's law is implemented in the visual system and we show that neurons in monkey area V1 use knowledge of eye torsion to compensate the image tilt associated with specific eye positions as set by Listing's law.


Assuntos
Movimentos Oculares/fisiologia , Neurônios/fisiologia , Córtex Visual , Animais , Macaca mulatta , Masculino , Estimulação Luminosa , Córtex Visual/citologia , Córtex Visual/fisiologia
8.
Zh Nevrol Psikhiatr Im S S Korsakova ; 120(6. Vyp. 2): 54-60, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32729691

RESUMO

OBJECTIVE: To determine the network connections between clinical, cognitive, speech and oculographic parameters in patients with schizophrenia. MATERIAL AND METHODS: The study included 104 patients with schizophrenia and schizophrenia spectrum disorders and 70 healthy subjects. Clinical assessment of the patients was performed using a number of scales: PANSS, CDSS, YMRS, SAS and BAS. Basic cognitive functions were assessed by BACS. Eye movements were recorded using the SMI RED-500 non-invasive eye tracking system. Several experimental paradigms were used - free viewing of animal images with subsequent description of these images, performing progressive saccades in the experimental Go/NoGo scheme, and performing anti-saccades. RESULTS: The severity of clinical symptoms, cognitive impairments, oculomotor parameters and characteristics of speech structure of written speech are largely independent, although not completely isolated from each other. Cognitive and oculomotor parameters have the largest number of connections. In this case, the results of cognitive tests are the central element of the «network¼ that connects other groups. CONCLUSION: Further development of the approach should be aimed at studying the influence of node changes on the structure of the network that would potentially allows the identification of the most effective points of application of therapeutic and rehabilitation programs.


Assuntos
Movimentos Oculares , Esquizofrenia , Animais , Cognição , Humanos , Movimentos Sacádicos , Fala
9.
Fa Yi Xue Za Zhi ; 36(2): 229-232, 2020 Apr.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32530172

RESUMO

Abstract: Objective To investigate the application value of eye tracking in lie detection. Methods The 40 subjects were randomly divided into two groups. The pupil diameter, fixation duration, points of fixation and blink frequency of the subjects in the experimental group in observing target stimulation and non-target stimulation were recorded with eye tracker after they accomplished the mock crime. The eye movement parameters of subjects in the control group were directly collected. The differences in eye movement parameters of the experimental group and the control group in observing target stimulation and non-target stimulation were analyzed by t-test. Pearson coefficient analysis of correlation between eye movement parameters that had differences was conducted. The effectiveness of eye movement parameters to distinguish between the experimental group and the control group was calculated by the receiver operator characteristic (ROC) curve. Results Participants from the experimental group had shorter average pupil diameter, longer average fixation duration and fewer fixation points (P<0.05), but the differences in blink frequency had no statistical significance. The differences in the above indicators of the control group in observing target stimulation and non-target stimulation had no statistical significance. The average fixation duration showed a negative correlation with fixation points (r=-0.255, P<0.05); the average fixation duration showed a negative correlation with average pupil diameter (r=-0.218, P<0.05); the fixation points showed a positive correlation with average pupil diameter (r=0.09, P<0.05). The area under the curve of average pupil diameter, average fixation duration and fixation points was 0.603, 0.621 and 0.580, respectively. Conclusion The average pupil diameter, average fixation duration and fixation points obtained by the eye tracker under laboratory conditions can be used to detect lies.


Assuntos
Detecção de Mentiras , Pupila , Algoritmos , Movimentos Oculares , Humanos , Fatores de Tempo
10.
Fa Yi Xue Za Zhi ; 36(2): 233-238, 2020 Apr.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32530173

RESUMO

Abstract: Objective To analyze the differences in accuracy of different eye movement parameters in distinguishing the cooperation and non-cooperation during image completion test of patients with mental disorders caused by craniocerebral trauma. Methods One hundred and forty cases of patients with mental disorders caused by craniocerebral trauma who took psychiatric impairment assessments were collected. The 21 pictures from "image completion" of Wechsler intelligence test were used as stimulating pictures, then divided into cooperation group and non-cooperation group according to binomial forced-choice digit memory test and expert opinions. The eye movement parameters of research subjects during completion of images were obtained by the SMI eye-tracker. The accuracy of eye movement parameters in distinguishing the cooperation or non-cooperation of patients with mental disorders caused by craniocerebral trauma in psychiatric impairment assessments were evaluated by the ROC curve. Results During the process of the image completion test, the area under curve (AUC) value of frequency of blink, frequency of fixation, pupil size, frequency of saccade, latency of saccade, average acceleration of saccade, the average and peak longitudinal velocity of saccade was above 0.5. When it comed to a specific stimulating picture, the AUC value of frequency of blink in looking at a specific stimulating picture could be above 0.8, and the AUC value of X axis diameter of pupil size could be above 0.7. Conclusion The accuracy of eye movement parameters in distinguishing the cooperation or disguise of patients with mental disorders caused by craniocerebral trauma is related with the stimulating picture. The accuracy of frequency of blink in distinguishing cooperation and non-cooperation is better than that of other eye movement parameters.


Assuntos
Movimentos Oculares , Piscadela , Humanos , Testes de Inteligência
11.
Stud Health Technol Inform ; 270: 287-291, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32570392

RESUMO

Eye tracking studies have demonstrated deficits in attention in individuals with Autism Spectrum Disorder (ASD) for a range of different social attention-based tasks. Here we examined social attention skills in a large sample of ASD participants (n = 120), using eye tracking data from a social information processing task, and compared them with a typically developing (TD) group (n = 35). Assuming eye movement parameters are random variables generated by an underlying stochastic process, we modeled the fixation sequences of participants in ASD and TD groups with a Hidden Markov Model. The Regions of Interests (ROIs), modeled as hidden states, corresponded to the true ROIs with a prediction accuracy of >90% for each group. The transition between ROIs revealed bias towards a specific area in the scene in ASD group, which deviated from the TD group. Objective time-dynamic measures of gaze patterns can potentially serve as useful endpoints in ASD diagnosis. Clinical Trial Registration: NCT02299700.


Assuntos
Atenção/fisiologia , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/fisiopatologia , Movimentos Oculares/fisiologia , Fixação Ocular/fisiologia , Aprendizagem/fisiologia , Estudos de Casos e Controles , Humanos , Cadeias de Markov , Comportamento Social , Habilidades Sociais , Processos Estocásticos
12.
PLoS One ; 15(6): e0233968, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32512583

RESUMO

In adults, words are more effective than sounds at activating conceptual representations. We aimed to replicate these findings and extend them to infants. In a series of experiments using an eye tracker object recognition task, suitable for both adults and infants, participants heard either a word (e.g. cow) or an associated sound (e.g. mooing) followed by an image illustrating a target (e.g. cow) and a distracter (e.g. telephone). The results showed that adults reacted faster when the visual object matched the auditory stimulus and even faster in the word relative to the associated sound condition. Infants, however, did not show a similar pattern of eye-movements: only eighteen-month-olds, but not 9- or 12-month-olds, were equally fast at recognizing the target object in both conditions. Looking times, however, were longer for associated sounds, suggesting that processing sounds elicits greater allocation of attention. Our findings suggest that the advantage of words over associated sounds in activating conceptual representations emerges at a later stage during language development.


Assuntos
Linguagem Infantil , Percepção da Fala , Percepção Visual , Adolescente , Adulto , Atenção , Criança , Pré-Escolar , Movimentos Oculares , Feminino , Humanos , Lactente , Som , Vocabulário , Adulto Jovem
13.
PLoS One ; 15(6): e0235342, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32598385

RESUMO

This report elaborates on adaptations of the eyes of the whale shark Rhincodon typus (Elasmobranchii, Rhincodontidae), including the discovery that they are covered with dermal denticles, which is a novel mechanism of eye protection in vertebrates. The eye denticle differs in morphology from that of the dermal denticles distributed over the rest of the body, consistent with a different function (abrasion resistance). We also demonstrate that the whale shark has a strong ability to retract the eyeball into the eye socket. The retraction distance was calculated to be approximately half the diameter of the eye, which is comparable to those of other vertebrates that are known to have highly retractable eyes. These highly protective features of the whale shark eye seem to emphasize the importance of vision for environmental perception, which contradicts the general, though poorly established, notion of low reliance on vision in this species.


Assuntos
Movimentos Oculares/fisiologia , Olho/anatomia & histologia , Olho/fisiopatologia , Tubarões/anatomia & histologia , Tubarões/fisiologia , Animais
14.
PLoS One ; 15(6): e0233915, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32484819

RESUMO

Cognitive control and incentive sensitivity are related to overeating and obesity. Optimal white matter integrity is relevant for an efficient interaction among reward-related brain regions. However, its relationship with sensitivity to incentives remains controversial. The aim of this study was to assess the incentive sensitivity and its relationship to white matter integrity in normal-weight and overweight groups. Seventy-six young adults participated in this study: 31 were normal-weight (body mass index [BMI] 18.5 to < 25.0 kg/m2, 14 females) and 45 were overweight (BMI ≥ 25.0 kg/m2, 22 females). Incentive sensitivity was assessed using an antisaccade task that evaluates the effect of incentives (neutral, reward, and loss avoidance) on cognitive control performance. Diffusion tensor imaging studies were performed to assess white matter integrity. The relationship between white matter microstructure and incentive sensitivity was investigated through tract-based spatial statistics. Behavioral antisaccade results showed that normal-weight participants presented higher accuracy (78.0 vs. 66.7%, p = 0.01) for loss avoidance incentive compared to overweight participants. Diffusion tensor imaging analysis revealed a positive relationship between fractional anisotropy and loss avoidance accuracy in the normal-weight group (p < 0.05). No relationship reached significance in the overweight group. These results support the hypothesis that white matter integrity is relevant for performance in an incentivized antisaccade task.


Assuntos
Encéfalo/diagnóstico por imagem , Sistema Nervoso Central/fisiopatologia , Cognição/fisiologia , Obesidade/fisiopatologia , Adulto , Anisotropia , Índice de Massa Corporal , Encéfalo/fisiologia , Mapeamento Encefálico , Sistema Nervoso Central/diagnóstico por imagem , Chile/epidemiologia , Imagem de Tensor de Difusão , Movimentos Oculares/fisiologia , Feminino , Humanos , Masculino , Obesidade/diagnóstico por imagem , Obesidade/epidemiologia , Perda de Peso/fisiologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Adulto Jovem
15.
J Vis Exp ; (159)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32538905

RESUMO

Researchers usually theorize media exposure based on assumptions of legacy media. However, a new interactive video viewing format, in this case barrage video where viewers' comments are overlaid over visual content, challenges past perspectives. This study proposes an activation and match satisfaction model to study viewing behaviors of lonely people and to challenge previous claims. It presents a protocol to examine the mechanism of how loners use barrage videos by combining eye tracking and self-report measures. Eye tracking documents the audience's conscious and subconscious watching behaviors in real time and allows for inference of the amount of allocated cognitive resources in response to rational and emotional content. The self-report gauges the amount of satisfaction obtained. Overall, results from the measures supported an activation and match satisfaction model regarding loners and their barrage video viewing behaviors. Implications are discussed.


Assuntos
Movimentos Oculares/fisiologia , Solidão/psicologia , Gravação em Vídeo/métodos , Adolescente , Adulto , Humanos , Adulto Jovem
16.
Nature ; 582(7812): E6-E8, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555493
17.
PLoS One ; 15(4): e0232246, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353030

RESUMO

INTRODUCTION: Observational gait analysis is a widely used skill in physical therapy. Meanwhile, the skill has not been investigated using objective assessments. The present study investigated the differences in eye movement between professionals and trainees, while observing gait analysis. METHODS: The participants included in this study were 26 professional physical therapists and 26 physical therapist trainees. The participants, wearing eye tracker systems, were asked to describe gait abnormalities of a patient as much as possible. The eye movement parameters of interest were fixation count, average fixation duration, and total fixation duration. RESULTS: The number of gait abnormalities described was significantly higher in professionals than in trainees, overall and in limbs of the patient. The fixation count was significantly higher in professionals when compared to trainees. Additionally, the average fixation duration and total fixation duration were significantly shorter in professionals. Conversely, in trunks, the number of gait abnormalities and eye movements showed no significant differences between groups. CONCLUSIONS: Professionals require shorter fixation durations on areas of interest than trainees, while describing a higher number of gait abnormalities.


Assuntos
Movimentos Oculares/fisiologia , Marcha/fisiologia , Feminino , Fixação Ocular/fisiologia , Análise da Marcha/métodos , Humanos , Masculino , Apoio ao Desenvolvimento de Recursos Humanos/métodos
18.
Proc Natl Acad Sci U S A ; 117(20): 11178-11183, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32358186

RESUMO

It is known that attention shifts prior to a saccade to start processing the saccade target before it lands in the foveola, the high-resolution region of the retina. Yet, once the target is foveated, microsaccades, tiny saccades maintaining the fixated object within the fovea, continue to occur. What is the link between these eye movements and attention? There is growing evidence that these eye movements are associated with covert shifts of attention in the visual periphery, when the attended stimuli are presented far from the center of gaze. Yet, microsaccades are primarily used to explore complex foveal stimuli and to optimize fine spatial vision in the foveola, suggesting that the influences of microsaccades on attention may predominantly impact vision at this scale. To address this question we tracked gaze position with high precision and briefly presented high-acuity stimuli at predefined foveal locations right before microsaccade execution. Our results show that visual discrimination changes prior to microsaccade onset. An enhancement occurs at the microsaccade target location. This modulation is highly selective and it is coupled with a drastic impairment at the opposite foveal location, just a few arcminutes away. This effect is strongest when stimuli are presented closer to the eye movement onset time. These findings reveal that the link between attention and microsaccades is deeper than previously thought, exerting its strongest effects within the foveola. As a result, during fixation, foveal vision is constantly being reshaped both in space and in time with the occurrence of microsaccades.


Assuntos
Atenção/fisiologia , Movimentos Oculares/fisiologia , Fóvea Central/fisiologia , Movimentos Sacádicos/fisiologia , Visão Ocular/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Percepção Visual , Adulto Jovem
19.
PLoS One ; 15(5): e0233008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392271

RESUMO

The present study examined emotional facial perception (happy and angry) in 7, 9 and 11-year-old children from Caucasian and multicultural environments with an offset task for two ethnic groups of faces (Asian and Caucasian). In this task, participants were required to respond to a dynamic facial expression video when they believed that the first emotion presented had disappeared. Moreover, using an eye-tracker, we evaluated the ocular behavior pattern used to process these different faces. The analyses of reaction times do not show an emotional other-race effect (i.e., a facility in discriminating own-race faces over to other-race ones) in Caucasian children for Caucasian vs. Asian faces through offset times, but an effect of emotional face appeared in the oldest children. Furthermore, an eye-tracked ocular emotion and race-effect relative to processing strategies is observed and evolves between age 7 and 11. This study strengthens the interest in advancing an eye-tracking study in developmental and emotional processing studies, showing that even a "silent" effect should be detected and shrewdly analyzed through an objective means.


Assuntos
Emoções , Expressão Facial , Reconhecimento Facial , Ira , Grupo com Ancestrais do Continente Asiático , Criança , Desenvolvimento Infantil , Grupo com Ancestrais do Continente Europeu , Medições dos Movimentos Oculares , Movimentos Oculares , Feminino , Fixação Ocular , Felicidade , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Reconhecimento Psicológico
20.
PLoS One ; 15(4): e0230866, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32352984

RESUMO

Faces are one of the most important stimuli that we encounter, but humans vary dramatically in their behavior when viewing a face: some individuals preferentially fixate the eyes, others fixate the mouth, and still others show an intermediate pattern. The determinants of these large individual differences are unknown. However, individuals with Autism Spectrum Disorder (ASD) spend less time fixating the eyes of a viewed face than controls, suggesting the hypothesis that autistic traits in healthy adults might explain individual differences in face viewing behavior. Autistic traits were measured in 98 healthy adults recruited from an academic setting using the Autism-Spectrum Quotient, a validated 50-statement questionnaire. Fixations were measured using a video-based eye tracker while participants viewed two different types of audiovisual movies: short videos of talker speaking single syllables and longer videos of talkers speaking sentences in a social context. For both types of movies, there was a positive correlation between Autism-Spectrum Quotient score and percent of time fixating the lower half of the face that explained from 4% to 10% of the variance in individual face viewing behavior. This effect suggests that in healthy adults, autistic traits are one of many factors that contribute to individual differences in face viewing behavior.


Assuntos
Atenção , Transtorno do Espectro Autista/psicologia , Face , Adolescente , Adulto , Movimentos Oculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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