Role of Foveal and Peripheral Visual Information in Maintenance of Postural Equilibrium in Man

1980 ◽  
Vol 51 (3) ◽  
pp. 903-912 ◽  
Author(s):  
Bernard Amblard ◽  
Abel Carblanc

In a previous report (Amblard & Crémieux, 1976) we demonstrated that the maintenance of postural equilibrium, measured with the subject in Mann's stance on a foam rubber support, was significantly more difficult under stroboscopic rather than normal lighting conditions. The most plausible cause of the difficulty is the subject's loss of visual perception of movement as a result of the stroboscopic lighting. The present study was designed to look at this factor under normal lighting conditions. Also, the relative contributions of foveal and peripheral vision were assessed. During stance, the subjects (5 women and 6 men, aged from 25 to 55 yr.) viewed either a horizontal or a vertical rectangular grating. With horizontal lines, the visual perception of lateral movement is minimized. Lateral acceleration was measured at three anatomical levels: ankles, hips, and head. The horizontal stripe condition was significantly less effective than the vertical stripe one for maintenance of balance, both for measurements at the head level only and for values averaged from all three levels. Balance was significantly impaired with foveal vision alone compared to full vision or to peripheral vision alone, for measurements from each of the three levels. We conclude that the visual perception of movement is a very important factor in the maintenance of the equilibrium, peripheral vision playing the major role, and foveal vision only a supplementary one.

Author(s):  
Ralph Schumacher

The aim of this paper is to defend a broad concept of visual perception, according to which it is a sufficient condition for visual perception that subjects receive visual information in a way which enables them to give reliably correct answers about the objects presented to them. According to this view, blindsight, non-epistemic seeing, and conscious visual experience count as proper types of visual perception. This leads to two consequences concerning the role of the phenomenal qualities of visual experiences. First, phenomenal qualities are not necessary in order to see something, because in the case of blindsight, subjects can see objects without experiences phenomenal qualities. Second, they cannot be intentional properties, since they are not essential properties of visual experiences, and because the content of visual experiences cannot be constituted by contingent properties.


1986 ◽  
Vol 30 (6) ◽  
pp. 599-600
Author(s):  
Michael Venturino ◽  
Edward J. Rinalducci

Technological advances have signi-ficantly altered the nature of the man-machine inter-face. Notable changes include: 1) a redefinition of the role of the human from that of a manual operator to a monitor/manager of complex systems; and 2) the availability of large amounts of data, presented or updated at rapid rates. As a result of such changes, the human operator must monitor, integrate, evaluate, and utilize continually changing information from a large number of spatially separated displays. Such demands require complex scanning patterns among numerous displays, and maintaining large amounts of information in working memory. These requirements and demands often overload the human's limited processing capabilities, and lead to degraded performance and increased probability of error. One possible solution to this propagation of displays and consequent information overload is to make more efficient use of human visual capabilities by offloading some types of information from foveal vision to peripheral vision. If appropriate types of information are presented to each aspect of vision (foveal and peripheral), then the human operator's bandwidth of information intake may be usefully increased. However, significant issues must be addressed before attempts are made to design peripheral displays. Such issues may be grouped into three categories: 1) determine the characteristics of peripheral vision relevant to display design (e.g., luminance sensitivity, contrast sensitivity, and acuity); 2) determine the characteristics of peripheral information processing (e.g., the costs and benefits of covert orienting of attention, the effects of foveal load on peripheral processing and vice-versa, and events in peripheral vision that cause a saccade); and 3) determine what types of information structure provide useful information in peripheral vision, which would indicate what types of information should be displayed in peripheral vision. The answers to these issues will provide data that may help determine whether it is feasible to display useable information to both foveal and peripheral vision, and provide guidelines for the design of peripheral displays. The purpose of this symposium is to address theoretical and applied issues of peripheral vision. The description and evaluation of the properties and characteristics of peripheral vision will serve as fundamental knowledge in determining the feasibility and design of peripheral displays. The symposium will be empirical in nature, with the participants presenting experimental data relevant to the above issues.


1984 ◽  
Vol 11 (3) ◽  
pp. 645-664 ◽  
Author(s):  
Elaine S. Andersen ◽  
Anne Dunlea ◽  
Linda S. Kekelis

ABSTRACTAlthough the role of visual perception is central to many theories of language development, researchers have disagreed sharply on the effects of blindness on the acquisition process: some claim major differences between blind and sighted children; others find great similarities. With audio-and video-recorded longitudinal data from six children (with varying degrees of vision) aged 0; 9–3; 4, we show that there ARE basic differences in early language, which appear to reflect differences in cognitive development. We focus here on early lexical acquisition and on verbal role-play, demonstrating how previous analyses have failed to observe aspects of the blind child's language system because language was considered out of the context of use. While a comparison of early vocabularies does suggest surface similarities, we found that when sighted peers are actively forming hypotheses about word meanings, totally blind children are acquiring largely unanalysed ‘labels’. They are slow to extend words and rarely overextended any. Similarly, although verbal role-play appears early, attempts to incorporate this kind of language into conversations with others reveal clear problems with reversibility – specifically, the ability to understand the role of shifting perspectives in determining word meaning. Examination of language in context suggests that blind children have difficulties in just those areas of language acquisition where visual information can provide input about the world and be a stimulus for forming hypotheses about pertinent aspects of the linguistic system.


2014 ◽  
Vol 4 ◽  
Author(s):  
Marc Boucher

My contribution to critical and artistic dialogues within the intersecting fields of dance and screen-based images consists in examining the role of peripheral vision in the perception of dance in artistic contexts where projections are used. There is, as I will point out, sufficient evidence from phenomenological and neuro-physiological accounts to conclude that motion perception is affected by peripheral visual perceptions. Consequently, it is maintained that the spectator’s experience of dance, especially when screens are involved, depends to some degree on peripheral visual perception, which in turn contributes to proprioception.


2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Andrew M Haun

Abstract It is sometimes claimed that because the resolution and sensitivity of visual perception are better in the fovea than in the periphery, peripheral vision cannot support the same kinds of colour and sharpness percepts as foveal vision. The fact that a scene nevertheless seems colourful and sharp throughout the visual field then poses a puzzle. In this study, I use a detailed model of human spatial vision to estimate the visibility of certain properties of natural scenes, including aspects of colourfulness, sharpness, and blurriness, across the visual field. The model is constructed to reproduce basic aspects of human contrast and colour sensitivity over a range of retinal eccentricities. I apply the model to colourful, complex natural scene images, and estimate the degree to which colour and edge information are present in the model’s representation of the scenes. I find that, aside from the intrinsic drift in the spatial scale of the representation, there are not large qualitative differences between foveal and peripheral representations of ‘colourfulness’ and ‘sharpness’.


2021 ◽  
Author(s):  
Yusuke Nakashima ◽  
So Kanazawa ◽  
Masami K. Yamaguchi

AbstractRecurrent loops in the visual cortex play a critical role in visual perception, which is likely not mediated by purely feedforward pathways. However, the development of recurrent loops is poorly understood. The role of recurrent processing has been studied using visual backward masking, a perceptual phenomenon in which a visual stimulus is rendered invisible by a following mask, possibly because of the disruption of recurrent processing. Anatomical studies have reported that recurrent pathways are immature in early infancy. This raises the possibility that younger infants process visual information mainly in a feedforward manner, and thus, they might be able to perceive visual stimuli that adults cannot see because of backward masking. Here, we show that infants under 7 months of age are immune to visual backward masking and that masked stimuli remain visible to younger infants while older infants cannot perceive them. These results suggest that recurrent processing is immature in infants under 7 months and that they are able to perceive objects even without recurrent processing. Our findings indicate that the algorithm for visual perception drastically changes in the second half of the first year of life.


Author(s):  
Zozulia I.Ye. ◽  
Stadnii A.S.

The article offers experimental material on methods of teaching global reading to foreign students, which was used by teachers-speakers of Vinnytsia National Technical University. Global reading involves presenting the student with a whole word and I is designed for visual perception and the ability to memorize visual information. In this way, the foreign student does not read the word in letters, but perceives it as a picture. The student reads in Ukrainian at once in words. However, unlike an image that depicts a particular object, it contains a generalized representation of the object, that is, it has a certain meaning. It was found that this method is especially helpful for students who use the hieroglyphic writing system in their native language.During the traditional analytical-synthetic reading, the student must first learn sounds, letters, then sequential compound reading and finally – merged reading of words. Learning to read analytically is often associated with difficulties, as it involves visual perception, concentration, and analytical-synthetic mental activity. As a result students spend more time and effort.First, students read familiar tokens that start with different letters, from short to long. Then move from words to phrases, and then from phrases to reading texts. The page can contain 2–3 sentences in large font. Up to 20 such sentences should be read per day. Since foreign students enter universities after studying the Ukrainian language, it is desirable that these sentences (texts) should be of a scientific style.Global reading should not be limited just to demonstrating and naming picture words. Tasks can be varied and carried out in the form of a game. The article gives examples of games and tasks that were used in our work with foreign students in order to consolidate knowledge.The advantages of using the method of global reading in the process of learning Ukrainian as a foreign language are established. This method helps students understand language as a holistic system and observe the paradigmatic relationship between its units, more quickly master reading, enrich vocabulary, take an active part in the learning process. Students’ own results significantly motivate them to learn the language, as they notice it from the first days of study, and the opportunity to use knowledge in learning and life.Key words: foreign student, second foreign language, non-traditional methods, flash-cards, game forms. У статті запропоновано експериментальний матеріал із методики навчання іноземних студентів гло-бального читання, який використали викладачі-мовники Вінницького національного технічного універси-тету.Глобальне читання передбачає представлення студентові цілого слова й розраховане на зорове сприй-няття та здатність до запам’ятовування візуальної інформації. У такий спосіб іноземний студент не читає слово по буквах, а сприймає його як картинку й читає українською мовою одразу словами. Однак на відміну від зображення, на якому представлено якийсь конкретний предмет, воно містить узагальнене уявлення про об’єкт, тобто має певне значення. З’ясовано, що цей метод особливо ефективно допомагає студентам, в яких у рідній мові використовують ієрогліфічну систему письма.Під час традиційного аналітико-синтетичного читання студент повинен спочатку засвоїти звуки, букви, потім послідовне поскладове читання та врешті – злите читання слів. Навчання аналітичного читання нерідко пов’язане з труднощами, оскільки передбачає і зорове сприйняття, і концентрацію уваги, й аналітико-синтетичну розумову діяльність. У результаті студенти витрачають більше часу й зусиль.Спочатку студенти читають відомі їм лексеми, які починаються з різних літер, від коротких до довших. Потім переходять від слів до фраз, а далі від фраз до читання текстів. На сторінці може бути розміщено 2–3 речення шрифтом великого розміру. За день студенту варто прочитати до 20 таких речень. Оскільки іноземні студенти після вивчення української мови вступають до університетів, то бажано, щоб ці речення (тексти) були наукового стилю.Глобальне читання не варто обмежувати демонстрацією та називанням слів, відтворених на флешкартках. Завдання можна урізноманітнити й проводити в ігровій формі. У статті наведено приклади ігор і завдань, які використовували в нашій роботі з іноземними студентами з метою закріплення знань.Установлено переваги використання методу глобального читання в процесі вивчення української мови як іноземної. Цей метод сприяє тому, що іноземні студенти розуміють мову як цілісну систему й спостерігають парадигматичні відношення між її одиницями, швидше опановують читання, збагачують словниковий запас, беруть активну участь у процесі навчання. Значно мотивують до вивчення мови власні результати, які студенти помічають уже з перших днів навчання, та можливості використати знання в навчанні й житті.Ключові слова: іноземний студент, друга іноземна мова, нетрадиційні методи, флешкартки, ігрові форми.


Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3327
Author(s):  
Vicente Román ◽  
Luis Payá ◽  
Adrián Peidró ◽  
Mónica Ballesta ◽  
Oscar Reinoso

Over the last few years, mobile robotics has experienced a great development thanks to the wide variety of problems that can be solved with this technology. An autonomous mobile robot must be able to operate in a priori unknown environments, planning its trajectory and navigating to the required target points. With this aim, it is crucial solving the mapping and localization problems with accuracy and acceptable computational cost. The use of omnidirectional vision systems has emerged as a robust choice thanks to the big quantity of information they can extract from the environment. The images must be processed to obtain relevant information that permits solving robustly the mapping and localization problems. The classical frameworks to address this problem are based on the extraction, description and tracking of local features or landmarks. However, more recently, a new family of methods has emerged as a robust alternative in mobile robotics. It consists of describing each image as a whole, what leads to conceptually simpler algorithms. While methods based on local features have been extensively studied and compared in the literature, those based on global appearance still merit a deep study to uncover their performance. In this work, a comparative evaluation of six global-appearance description techniques in localization tasks is carried out, both in terms of accuracy and computational cost. Some sets of images captured in a real environment are used with this aim, including some typical phenomena such as changes in lighting conditions, visual aliasing, partial occlusions and noise.


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