scholarly journals Attention Trade-Off for Localization and Saccadic Remapping

Vision ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 24
Author(s):  
Anna Dreneva ◽  
Ulyana Chernova ◽  
Maria Ermolova ◽  
William Joseph MacInnes

Predictive remapping may be the principal mechanism of maintaining visual stability, and attention is crucial for this process. We aimed to investigate the role of attention in predictive remapping in a dual task paradigm with two conditions, with and without saccadic remapping. The first task was to remember the clock hand position either after a saccade to the clock face (saccade condition requiring remapping) or after the clock being displaced to the fixation point (fixation condition with no saccade). The second task was to report the remembered location of a dot shown peripherally in the upper screen for 1 s. We predicted that performance in the two tasks would interfere in the saccade condition, but not in the fixation condition, because of the attentional demands needed for remapping with the saccade. For the clock estimation task, answers in the saccadic trials tended to underestimate the actual position by approximately 37 ms while responses in the fixation trials were closer to veridical. As predicted, the findings also revealed significant interaction between the two tasks showing decreased predicted accuracy in the clock task for increased error in the localization task, but only for the saccadic condition. Taken together, these results point at the key role of attention in predictive remapping.

Author(s):  
Ziqing Yao ◽  
Xuanyi Lin ◽  
Xiaoqing Hu

Abstract When people are confronted with feedback that counters their prior beliefs, they preferentially rely on desirable rather than undesirable feedback in belief updating, i.e. an optimism bias. In two pre-registered EEG studies employing an adverse life event probability estimation task, we investigated the neurocognitive processes that support the formation and the change of optimism biases in immediate and 24 h delayed tests. We found that optimistic belief updating biases not only emerged immediately but also became significantly larger after 24 h, suggesting an active role of valence-dependent offline consolidation processes in the change of optimism biases. Participants also showed optimistic memory biases: they were less accurate in remembering undesirable than desirable feedback probabilities, with inferior memories of undesirable feedback associated with lower belief updating in the delayed test. Examining event-related brain potentials (ERPs) revealed that desirability of feedback biased initial encoding: desirable feedback elicited larger P300s than undesirable feedback, with larger P300 amplitudes predicting both higher belief updating and memory accuracies. These results suggest that desirability of feedback could bias both online and offline memory-related processes such as encoding and consolidation, with both processes contributing to the formation and change of optimism biases.


2014 ◽  
Vol 21 (6) ◽  
pp. 382-386 ◽  
Author(s):  
Ch Jo ◽  
Jh Ahn ◽  
Yd Shon ◽  
Gc Cho

Introduction The aim of this study was to determine the effect of hand positioning on the quality of external chest compression (ECC) by novice rescuers. Methods This observational simulation study was conducted for 117 included participants. After completion of an adult cardiopulmonary resuscitation (CPR) training program for 3-h, the participants selected which of their hands would be in contact with the mannequin during ECC and performed 5 cycles of single rescuer CPR on a recording mannequin. The participants were assigned to 2 groups: the dominant hand group (DH; n=40) and the non-dominant hand group (NH; n=29). The depth and rate of ECC were analysed to compare the effectiveness of ECC between 2 groups. Results The rate of ECC was significantly faster in the DH group (mean, 117.3 ±11.4/min) than in the NH group (mean, 110.9±12.2/min) (p=0.028). However, the depth of ECC in the dominant hand group (mean, 52.4±5.9 mm) was not significantly different from that in the non-dominant hand group (mean, 50.8±6.0 mm) (p=0.287). Similarly, the portion of ECC with inadequate depth in the dominant hand group (mean, 1.8±4.3%) was not significantly different from that in the non-dominant hand group (mean, 5.3±15.6%) (p=0.252). Conclusions ECC can be performed with an acceptably higher rate of compressions when the dominant hand of the novice rescuer is placed in contact with the sternum. However, the position of the dominant hand does not affect the depth of ECC. (Hong Kong j.emerg.med. 2014;21:382-386)


2018 ◽  
Author(s):  
Tao He ◽  
Matthias Fritsche ◽  
Floris P. de Lange

AbstractVisual stability is thought to be mediated by predictive remapping of the relevant object information from its current, pre-saccadic locations to its future, post-saccadic location on the retina. However, it is heavily debated whether and what feature information is predictively remapped during the pre-saccadic interval. Using an orientation adaptation paradigm, we investigated whether predictive remapping occurs for stimulus features and whether adaptation itself is remapped. We found strong evidence for predictive remapping of a stimulus presented shortly before saccade onset, but no remapping of adaptation. Furthermore, we establish that predictive remapping also occurs for stimuli that are not saccade targets, pointing toward a ‘forward remapping’ process operating across the whole visual field. Together, our findings suggest that predictive feature remapping of object information plays an important role in mediating visual stability.


Author(s):  
Tsymbalista L.R.

Валентність предиката має вирішальний вплив на структуру речення. Хоча активний і пасивний варіанти речення опису-ють одну й ту ж ситуацію, предикат проходить крізь трансформацію, яка тісно пов’язана з явищем валентності. У цій статті проаналізовано валентність предиката та її вплив на цю трансформацію у німецькій та українській мовах на прикладах із сучасної літератури.Мета. Метою статті є порівняння трансформації «актив – пасив» у німецькій та українській мовах та опис ролі валентності у цьому процесі.Методи. Для проведення дослідження було зібрано методом суцільної вибірки приклади пасивних конструкцій із сучас-них художніх текстів німецькою та українською мовами, які опісля було оброблено та проаналізовано з використанням типо-логічного, зіставного, описового методів, а також методу моделювання.Валентність предиката проявляється у його здатності формувати зв’язки з іншими елементами в реченні та дає змогу передбачити додаткові позиції у синтаксичній структурі речення, які можуть бути заповнені обов’язковими чи факультатив-ними компонентами. Для предиката властиві два типи валентності, які залежать від позиції поширювачів у реченні. Якщо лівобічну позицію переважно пов’язують із суб’єктом, то правобічна зазвичай стосується актантів з об’єктним, адресатним, локативним чи інструментальним значеннями.Результати. Зважаючи на те, що одна й та ж функція пасивних конструкцій у німецькій та українській мовах реалізується різними формами, валентні зміни у кожній з конструкцій мають свої особливості. Спільною рисою цих перетворень виступає зменшення облігаторних актантів на одну одиницю, яка може бути заповнена факультативно у разі комунікативної потреби у інформації про виконавця дії.Висновки. Можна зробити висновок, що валентність предиката є багатогранним феноменом, що підлягає впливу не лише формально-граматичних, а й семантико-синтаксичних чинників, а також мовленнєвої ситуації загалом. Відповідно, змін у валентності предикатів протягом трансформації з активу у пасив не можна уникнути. The valence of the predicate has a decisive effect on the structure of the sentence. Although the active and passive variant of the sentence describes the same situation, the predicate goes through a transformation that also has to do with valence. This article analyzes the valency of the predicate and its influence on such transformation in German and Ukrainian based on the examples from modern literature.Purpose. The purpose of the article is to compare the active-passive transformation in German and Ukrainian and to describe the role of valence in this process.Methods. For the research, we collected the examples of passive constructions from modern fiction in German and Ukrainian using the continuous sampling method, which were then processed and analyzed using typological, comparative, descriptive methods as well as the modelling method.The valence of the predicate verb shows in its ability to connect with other sentence elements and enables the prediction of the additional positions in the syntactic structure of the sentence, which can be supplemented by mandatory or optional components. The predicate is characterized by two types of valence, which depend on the position of the fillers in the sentence: the left-hand position is mainly connected the subject of the utterance, and the right-hand position has to do with actants which define object, addressee, location or have instrumental meaning.Results. Due to the fact that the same function of passive constructions in German and Ukrainian is realized in different forms, the valence changes in each of the constructions have their own features. A common feature of these transformations is the reduction of obligatory actants by one unit, which can be filled in optionally in case of communicative need for information about the performer of the action.Conclusions. We reach the conclusion that the valence of the predicate is a multilevel phenomenon that is influenced not only by formal grammatical but also by semantic and syntactic factors as well as the language situation in general. Accordingly, changes in the valence of predicates during the active-passive transformation are inevitable.


2020 ◽  
Vol 7 (7) ◽  
pp. 191974
Author(s):  
Liutao Yu ◽  
Chundi Wang ◽  
Si Wu ◽  
Da-Hui Wang

Communication plays an important role in consensus decision-making which pervades our daily life. However, the exact role of communication in consensus formation is not clear. Here, to study the effects of communication on consensus formation, we designed a dyadic colour estimation task, where a pair of isolated participants repeatedly estimated the colours of discs until they reached a consensus or completed eight estimations, either with or without communication. We show that participants’ estimates gradually approach each other, reaching towards a consensus, and these are enhanced with communication. We also show that dyadic consensus estimation is on average better than individual estimation. Surprisingly, consensus estimation without communication generally outperforms that with communication, indicating that communication impairs the improvement of consensus estimation. However, without communication, it takes longer to reach a consensus. Moreover, participants who partially cooperate with each other tend to result in better overall consensus. Taken together, we have identified the effect of communication on the dynamics of consensus formation, and the results may have implications on group decision-making in general.


2019 ◽  
Vol 59 (1) ◽  
pp. 214-226 ◽  
Author(s):  
Alyssa Y Stark ◽  
Christopher T Mitchell

Abstract The gecko adhesive system has inspired hundreds of synthetic mimics principally focused on replicating the strong, reversible, and versatile properties of the natural system. For geckos native to the tropics, versatility includes the need to remain attached to substrates that become wet from high humidity and frequent rain. Paradoxically, van der Waals forces, the principal mechanism responsible for gecko adhesion, reduce to zero when two contacting surfaces separate even slightly by entrapped water layers. A series of laboratory studies show that instead of slipping, geckos maintain and even improve their adhesive performance in many wet conditions (i.e., on wet hydrophobic substrates, on humid substrates held at low temperatures). The mechanism for this is not fully clarified, and likely ranges in scale from the chemical and material properties of the gecko’s contact structures called setae (e.g., setae soften and change surface confirmation when exposed to water), to their locomotor biomechanics and decision-making behavior when encountering water on a substrate in their natural environment (e.g., some geckos tend to run faster and stop more frequently on misted substrates than dry). Current work has also focused on applying results from the natural system to gecko-inspired synthetic adhesives, improving their performance in wet conditions. Gecko-inspired synthetic adhesives have also provided a unique opportunity to test hypotheses about the natural system in semi-natural conditions replicated in the laboratory. Despite many detailed studies focused on the role of water and humidity on gecko and gecko-inspired synthetic adhesion, there remains several outstanding questions: (1) what, if any, role does capillary or capillary-like adhesion play on overall adhesive performance of geckos and gecko-inspired synthetics, (2) how do chemical and material changes at the surface and in the bulk of gecko setae and synthetic fibrils change when exposed to water, and what does this mean for adhesive performance, and (3) how much water do geckos encounter in their native environment, and what is their corresponding behavioral response? This review will detail what we know about gecko adhesion in wet environments, and outline the necessary next steps in biological and synthetic system investigations.


1997 ◽  
Vol 77 (2) ◽  
pp. 1034-1038 ◽  
Author(s):  
S. Ferraina ◽  
P. B. Johnson ◽  
M. R. Garasto ◽  
A. Battaglia-Mayer ◽  
L. Ercolani ◽  
...  

Ferraina, S., P. B. Johnson, M. R. Garasto, A. Battaglia-Mayer, L. Ercolani, L. Bianchi, F. Lacquaniti, and R. Caminiti. Combination of hand and gaze signals during reaching: activity in parietal area 7m of the monkey. J. Neurophysiol. 77: 1034–1038, 1997. The role of area 7m has been studied by recording the activity of single neurons of monkeys trained to fixate and reach toward peripheral targets. The target was randomly selected from eight possible locations on a virtual circle, of radius 30° visual angle from a central target. Three tasks were employed to dissociate hand- from eye-related contributions. In the first task, animals looked and reached to the peripheral target. In a second task, the animal reached to the peripheral target while maintaining fixation on the central target. In the third task, the monkey maintained fixation on peripheral targets that were spatially coincident with those of the reaching tasks. The results show that cell activity in area 7m relates, for some cells to eye position, for others to hand position and movement, and for the majority of cells to a combination of visuomanual and oculomotor information. This area, therefore, seems to perform an early combination of information in the processing leading from target localization to movement generation.


1969 ◽  
Vol 29 (2) ◽  
pp. 467-473 ◽  
Author(s):  
Israel Lieblich ◽  
Amia Lieblich

5 experiments were conducted in an attempt to produce a shift in the decision pattern in a forced-choice arithmetical estimation task. The expected shift was related to a change in the payoff matrix attached to the possible outcomes of the decision. The experiments varied in the amount of payoff, clarity of the explanation of the payoff matrix, difficulty of the task, feedback after decision and the length of decision time. None of these manipulations produced the expected rational shift. The role of payoff matrices in decisions in tasks involving skill is discussed.


1999 ◽  
Vol 125 (3) ◽  
pp. 281-286 ◽  
Author(s):  
J. D. Connolly ◽  
M. A. Goodale

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