scholarly journals Objective (Real-world) Motion Responses in Scene Responsive Regions

2017 ◽  
Author(s):  
Didem Korkmaz Hacialihafiz ◽  
Andreas Bartels

AbstractWe perceive scenes as stable even when eye movements induce retinal motion, for example during pursuit of a moving object. Mechanisms mediating perceptual stability have primarily been examined in motion regions of the dorsal visual pathway. Here we examined whether motion responses in human scene regions are encoded in eye- or world centered reference frames. We recorded brain responses in human participants using fMRI while they performed a well-controlled visual pursuit paradigm previously used to examine dorsal motion regions. In addition, we examined effects of content by using either natural scenes or their Fourier scrambles. We found that parahippocampal place area (PPA) responded to motion only in world- but not in eye-centered coordinates, regardless of scene content. The occipital place area (OPA) responded to both, objective and retinal motion equally, and retrosplenial cortex (RSC) had no motion responses but responded to pursuit. Only PPA’s objective motion responses were higher during scenes than scrambled images, although there was a similar trend in OPA. These results indicate a special role of PPA in representing its content in real-world coordinates. Our results question a strict subdivision of dorsal “what” and ventral “where” streams, and suggest a role of PPA in contributing to perceptual stability.


2021 ◽  
Author(s):  
Fatemeh Molaei Vaneghi ◽  
Natalia Zaretskaya ◽  
Tim van Mourik ◽  
Jonas Bause ◽  
Klaus Scheffler ◽  
...  

Neural mechanisms underlying a stable perception of the world during pursuit eye movements are not fully understood. Both, perceptual stability as well as perception of real (i.e. objective) motion are the product of integration between motion signals on the retina and efference copies of eye movements. Human areas V3A and V6 have previously been shown to have strong objective ('real') motion responses. Here we used high-resolution laminar fMRI at ultra-high magnetic field (9.4T) in human subjects to examine motion integration across cortical depths in these areas. We found an increased preference for objective motion in areas V3A and V6+ i.e. V6 and possibly V6A towards the upper layers. When laminar responses were detrended to remove the upper-layer bias present in all responses, we found a unique, condition-specific laminar profile in V6+, showing reduced mid-layer responses for retinal motion only. The results provide evidence for differential, motion-type dependent laminar processing in area V6+. Mechanistically, the mid-layer dip suggests a special contribution of retinal motion to integration, either in the form of a subtractive (inhibitory) mid-layer input, or in the form of feedback into extragranular or infragranular layers. The results show that differential laminar signals can be measured in high-level motion areas in human occipitoparietal cortex, opening the prospect of new mechanistic insights using non-invasive brain imaging.



2021 ◽  
Author(s):  
J. P. Shine ◽  
T. Wolbers

AbstractOrientation-specific head direction (HD) cells increase their firing rate to indicate one’s facing direction in the environment. Rodent studies suggest HD cells in distinct areas of thalamus and retrosplenial cortex (RSC) code either for global (relative to the wider environment) or local (e.g., room-specific) reference frames. To investigate whether similar neuroanatomical dissociations exist in humans, we reanalysed functional magnetic resonance imaging data in which participants learned the orientation of unique images in separate local environments relative to distinct global landmarks (Shine, Valdés-Herrera, Hegarty, & Wolbers, 2016). The environment layout meant that we could establish two separate multivariate analysis models in which the HD on individual trials was coded relative either to global (North, South, East, West) or local (Front, Back, Right, Left) reference frames. Examining the data first in key regions of interest (ROI) for HD coding, we replicated our previous results and found that global HD was decodable in the thalamus and precuneus; the RSC, however, was sensitive only to local HD. Extending recent findings in both humans and rodents, V1 was sensitive to both HD reference frames. Additional small volume-corrected searchlight analyses supported the ROI results and indicated that the anatomical locus of the thalamic global HD coding was located in the medial thalamus, bordering the anterior thalamus, a region critical for global HD coding in rodents. Our findings elucidate further the putative neural basis of HD coding in humans, and suggest that distinct brain regions code for different frames of reference in HD.Significance statementHead direction (HD) cells provide a neural signal as to one’s orientation in the environment. HD can be coded relative to global or local (e.g., room-specific) reference frames, with studies suggesting that distinct areas of thalamus and retrosplenial cortex (RSC) code for this information. We reanalysed fMRI data where human participants associated images with global HDs before undergoing scanning. The design enabled us to examine both global and local HD coding. Supporting previous findings, global HD was decodable in thalamus, however the RSC coded only for local HD. We found evidence also for both reference frames in V1. These findings elucidate the putative neural basis of HD coding in humans, with distinct brain regions coding for different HD reference frames.



2018 ◽  
Author(s):  
Didem Korkmaz Hacialihafiz ◽  
Andreas Bartels

AbstractCreating a stable perception of the world during pursuit eye movements is one of the everyday roles of visual system. Some motion regions have been shown to differentiate between motion in the external world from that generated by eye movements. However, in most circumstances, perceptual stability is consistently related to content: the surrounding scene is typically stable. However, no prior study has examined to which extent motion responsive regions are modulated by scene content, and whether there is an interaction between content and motion response. In the present study we used a factorial design that has previously been shown to reveal regional involvement in integrating efference copies of eye-movements with retinal motion to mediate perceptual stability and encode real-world motion. We then added scene content as a third factor, which allowed us to examine to which extent real-motion, retinal motion, and static responses were modulated by meaningful scenes versus their Fourier scrambled counterpart. We found that motion responses in human motion responsive regions V3A, V6, V5+/MT+ and cingulate sulcus visual area (CSv) were all modulated by scene content. Depending on the region, these motion-content interactions differentially depended on whether motion was self-induced or not. V3A was the only motion responsive region that also showed responses to still scenes. Our results suggest that contrary to the two-pathway hypothesis, scene responses are not isolated to ventral regions, but also can be found in dorsal areas.



2013 ◽  
pp. 143-155
Author(s):  
A. Klepach ◽  
G. Kuranov

The role of the prominent Soviet economist, academician A. Anchishkin (1933—1987), whose 80th birth anniversary we celebrate this year, in the development of ideas and formation of economic forecasting in the country at the time when the directive planning acted as a leading tool of economic management is explored in the article. Besides, Anchishkin’s special role is noted in developing a comprehensive program of scientific and technical progress, an information basis for working out long-term forecasts of the country’s development, moreover, his contribution to the creation of long-term forecasting methodology and improvement of the statistical basis for economic analysis and economic planning. The authors show that social and economic forecasting in the period after 1991, which has undertaken a number of functions of economic planning, has largely relied on further development of Anchishkin’s ideas, at the same time responding to new challenges for the Russian economy development during its entry into the world economic system.



2018 ◽  
Vol 28 (7) ◽  
pp. 2543-2548
Author(s):  
Petya Kasnakova

The games play a special role in rehabilitation practice. The positive emotions they cause in patients cannot be achieved by other methods and means of modern rehabilitation. The role of game playing activity in practice is crucial to the achievement of one of the important tasks in implementing rehabilitation measures, namely to evacuate the patient from the depressed mental state, to distract him from the disease process and to focus on mobilizing his healing powers. The mood, the emotional charge and the dynamics that the games create are particularly suited to awakening the patient's interest in the healing process, their attraction and their active involvement in the rehabilitation activities. The connection between the actions in the game and the movements in the analytical exercises accelerates the formation of motor habits, physical qualities and skills not only in children but also in adult patients with various pathological injuries. Rehabilitation games are suitable for all ages by enhancing the health of the occupants, developing their mental qualities, improving the activity of the vestibular, visual and motor analyzers. The basis of the motor movement training game methodology and the improvement of motor movement skills is the activation of the thought processes and emotional experiences, the development of the functions of the musculoskeletal system, the cardiovascular system and the respiratory system.



Author(s):  
Замира Сейткожоева

Аннотация: В статье обращено внимание на исключительную роль книги в жизни человека, воспитание молодежи. Книга сопровождает человека всю жизнь. Однако в последние годы замечается снижение интереса к чтению книг. Отдается предпочтение компьютеру, играм, телевизору, слушанию музыки через наушники. Во избежание деградации личности, в воспитании грамотной, гуманной, толерантной личности необходимо приучать подрастающее поколение к вдумчивому чтению книг. Значительное место в развитии личности занимает внеклассное чтение, к которому нужно прививать интерес еще во время учебы в младшем возрасте. В мире особая роль принадлежит межличностным отношениям, формированию такой личности, которая могла бы жить в согласии с носителями разных культур. Для формирования поликультурной личности важная роль принадлежит культурному наследию, основу которого составляют книги. Ключевые слова: роль книги, гуманная личность, толерантная личность, библиографические материалы, указатели библиографических данных, справочная литература, поликультурная личность, внеклассное чтение, информатизация, интерес к чтению. Аннотация: Макалада адамдын жашоосундагы жаштарды тарбиялоодогу китептин өзгөчө мааниси, ролуна өзгөчө көңүл бурулган. Бир эле мезгилде, соңку жылдарда китептерибизге болгон адамдардын кызыгууларды төмөндөп бараткандыгы байкалган.Учурда поли- же ар кандай оюндарга, телевизор көрүүгө, кулакчын аркылуу модалуу музыка угууга, артыкчылык берилип жатат. Билимдүү, гумандуу толеранттуу инсанды тарбиялап чыгууга да, анын деградацияга кабылышынан сактап калыш үчүн, өсүп келе жаткан муундарды өзүнүн айкалыштыра алуусу менен китептерди берилип жана ой жүгүртүп алууга үйрөтүү- өтө зарыл талап болуп эсептелет. Инсандын онүгүндө окуудан тышкаркы окуунун маанилүү орду бар. Мындай окууга буга кызыгуусун өркүндөтүүнун башталгыч каласстардан тарта үйрөтүү абзел. Инсандар аралык байланыштар дүйнөдө өзгөчө орун ээлейт, алар башка маданий өкүлдөрү менен макулдуктулукта жашоого даяр. Полимаданиятту инсандын калыптанышына ар маданияттын мурасы өтө чоң ролду ойнойт, анын негизин китептер түзөт. Түйүндүү сөздөр: китептин мааниси жана ролу, гумандуу инсан, толеранттуу инсан, библиографиялык материалдар, библиографиялык маалыматтарды көрсөтүү сурантыла билүү адабияты, полимаданиятуу инсан, окуудан тышкаркы окуу,маалымдуулук, окууга кызыгуу The article draws attention to the exceptional role of the book in human life, education of young people. The book accompanies a person all his life. However, in recent years, there has been a decline in interest in reading books. Preference is given to a computer, games, TV, listening to music through headphones. In order to avoid degradation of the personality, it is necessary to accustom the younger generation to thoughtful reading of books. a significant place in the development of personality takes extracurricular reading, to which you need to instill interest even while studying at a younger age. In the world a special role belongs to interpersonal relationship, the formation of such a personality, who could live in harmony with speakers of different cultures. To form a multicultural personality an important role belongs to cultural heritage, the basis of which are books Keywords: the role of the book, humane personality, tolerant personality, bibliographic materials, indexes of bibliographic data, reference literature, multicultural personality, extracurricular reading, informatization, interest in reading.



2019 ◽  
Vol 25 (22) ◽  
pp. 2467-2473 ◽  
Author(s):  
Enrique Reyes-Muñoz ◽  
Federica Di Guardo ◽  
Michal Ciebiera ◽  
Ilker Kahramanoglu ◽  
Thozhukat Sathyapalan ◽  
...  

Background: Gestational Diabetes Mellitus (GDM), defined as glucose intolerance with onset or first recognition during pregnancy, represents one of the most common maternal-fetal complications during pregnancy and it is associated with poor perinatal outcomes. To date, GDM is a rising condition over the last decades coinciding with the ongoing epidemic of obesity and Type 2 Diabetes Mellitus (T2DM). Objective: The aim of this review is to discuss the role of diet and nutritional interventions in preventing GDM with the explanation of the special role of myo-inositol (MI) in this matter. Methods: We performed an overview of the most recent literature data on the subject with particular attention to the effectiveness of diet and nutritional interventions in the prevention of GDM with the special role of MI. Results: Nutritional intervention and physical activity before and during pregnancy are mandatory in women affected by GDM. Moreover, the availability of insulin-sensitizers such as different forms of inositol has dramatically changed the scenario, allowing the treatment of several metabolic diseases, such as those related to glucose dysbalance. Although the optimal dose, frequency, and form of MI administration need to be further investigated, diet supplementation with MI appears to be an attractive alternative for the GDM prevention as well as for the reduction of GDM-related complications. Conclusion: More studies should be conducted to prove the most effective nutritional intervention in GDM. Regarding the potential effectiveness of MI, further evidence in multicenter, randomized controlled trials is needed to draw firm conclusions.



2018 ◽  
Vol 15 (13) ◽  
pp. 1191-1212 ◽  
Author(s):  
Botond Penke ◽  
Gábor Paragi ◽  
János Gera ◽  
Róbert Berkecz ◽  
Zsolt Kovács ◽  
...  

Lipids participate in Amyloid Precursor Protein (APP) trafficking and processing - important factors in the initiation of Alzheimer’s disease (AD) pathogenesis and influence the formation of neurotoxic β-amyloid (Aβ) peptides. An important risk factor, the presence of ApoE4 protein in AD brain cells binds the lipids to AD. In addition, lipid signaling pathways have a crucial role in the cellular homeostasis and depend on specific protein-lipid interactions. The current review focuses on pathological alterations of membrane lipids (cholesterol, glycerophospholipids, sphingolipids) and lipid metabolism in AD and provides insight in the current understanding of biological membranes, their lipid structures and functions, as well as their role as potential therapeutic targets. Novel methods for studying the membrane structure and lipid composition will be reviewed in a broad sense whereas the use of lipid biomarkers for early diagnosis of AD will be shortly summarized. Interactions of Aβ peptides with the cell membrane and different subcellular organelles are reviewed. Next, the details of the most important lipid signaling pathways, including the role of the plasma membrane as stress sensor and its therapeutic applications are given. 4-hydroxy-2-nonenal may play a special role in the initiation of the pathogenesis of AD and thus the “calpain-cathepsin hypothesis” of AD is highlighted. Finally, the most important lipid dietary factors and their possible use and efficacy in the prevention of AD are discussed.



Author(s):  
Laurence Publicover

This chapter analyses the ways in which the collaborative drama The Travels of the Three English Brothers defends the Sherley brothers’ real-world political endeavours across Europe and Persia through its intertheatrical negotiations. Explaining the political background of those endeavours and their controversial nature, it illustrates how the playwrights liken the Sherleys to the heroes of dramas that had been popular on the early modern stage over the preceding twenty years, in particular Tamburlaine and The Merchant of Venice. It also examines the significance of Francis Beaumont’s specific parody, in The Knight of the Burning Pestle, of an episode in Travels in which the Persian Sophy acts as godfather to the child of Robert Sherley. The chapter concludes with a discussion of the role of playing companies in shaping dramatic output.



Author(s):  
Martin Maiden

The chapter presents the role of stress and stress-related vocalic differentiation in creating a pattern of root allomorphy (the N-pattern), which distinguishes the singular and third-person forms of the present indicative and subjunctive, and of the imperative, from the rest of the paradigm. It is shown how numerous innovatory patterns (including suppletion, defectiveness, heteroclisis, and periphrases) replicate this pattern in diachrony. The possible role of markedness or of residual phonological conditioning is critically considered. It is suggested that the verb meaning ‘go’ may have played a special role. The independence of the N-pattern from extramorphological conditioning is reaffirmed.



Sign in / Sign up

Export Citation Format

Share Document