Visual Asymmetry Research Articles

Функциональная межполушарная асимметрия и нейрокогнитивное развитие у детей и подростков

<p>Many neuropsychologists believe that left-handed individuals are more likely to experience developmental disorders. In addition, non-coinciding lateralization of analyzers (cross-laterality) is also considered as a possible factor in dysontogenesis. However, in recent years it has been demonstrated that functional interhemispheric asymmetry (FIA) has minimal impact on intelligence and quality of life. This study aims to measure the contribution of manual and visual asymmetries to the overall level of neurocognitive development (ND) in children and adolescents. A total of 922 individuals were studied, including 594 boys and 328 girls aged 4–17 years, who underwent neuropsychological diagnostics. The scale of general level of development from the psychometric battery “Multifactorial Investigation of Neuropsychological Development” was used. The measurement of seven FIA indicators was carried out by observing subjects and assessing the performance on five techniques for lateral signs. No significant influence on ND was found for FIA and cross-lateralization. In some age groups, lateral signs were associated with ND, but this association was not stable. Additionally, it was shown that the results of techniques for lateral signs are inconsistent with each other.</p>

The influence of attention on visual asymmetries in the foveola

The influence of attention on visual asymmetries in the foveola

Gravity's impact on visual search asymmetries: Is visual gravitational motion a distinct visual feature or a familiar dynamic event?

A wealth of converging research lines has led support to the notion that specialized neural processes output a priori information about the expected effects of gravity to fine-tune motor and perceptual responses to dynamic events. Arguably, these putative internal models of gravity might modulate the efficiency in visual search for objects conforming or not to gravitationally coherent dynamics. In the present work, we explored this possibility with a visual search task involving arrays of two to eight objects moving periodically back and forth. The target could be an accelerating/decelerating ball (as if bouncing on earth's surface-1g) with distractors moving at a constant speed (0g) or the reverse. Moreover, the direction of the gravitational pull, as implied by the 1g motion patterns, could be aligned or misaligned with Earth's gravity. Overall, searches for 1g targets were more efficient than 0g targets except, notably, when stimuli displays were congruent with Earth's gravitational pull, in which case the visual search asymmetry is significantly reduced. Outcomes are interpreted as reflecting the joint and mutually cancelling contribution of low-level detection of acceleration patterns and higher level detection of unexpected violations of gravitational motion. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Mainly Visual Aspects of Emotional Laterality in Cognitively Developed and Highly Social Mammals-A Systematic Review.

Several studies have shown that emotions are asymmetrically represented in the human brain and have proposed three main models (the 'right hemisphere hypothesis', the 'approach-withdrawal hypothesis' and the 'valence hypothesis') that give different accounts of this emotional laterality. Furthermore, in recent years, many investigations have suggested that a similar emotional laterality may also exist in different animal taxa. However, results of a previous systematic review of emotional laterality in non-human primates have shown that some of these studies might be criticized from the methodological point of view and support only in part the hypothesis of a continuum in emotional laterality across vertebrates. The aim of the present review therefore consisted in trying to expand this survey to other cognitively developed and highly social mammals, focusing attention on mainly visual aspects of emotional laterality, in studies conducted on the animal categories of horses, elephants, dolphins and whales. The 35 studies included in the review took into account three aspects of mainly visual emotional laterality, namely: (a) visual asymmetries for positive/familiar vs. negative/novel stimuli; (b) lateral position preference in mother-offspring or other affiliative interactions; (c) lateral position preference in antagonistic interactions. In agreement with data obtained from human studies that have evaluated comprehension or expression of emotions at the facial or vocal level, these results suggest that a general but graded right-hemisphere prevalence in the processing of emotions can be found at the visual level in cognitively developed non-primate social mammals. Some methodological problems and some implications of these results for human psychopathology are briefly discussed.

Psychophysiological Characteristics of Athletes-Volleyball Players with Hearing Impairment

To reveal the features of the central nervous system and the severity of hemispheric asymmetry in volleyball athletes with hearing deprivation. Materials and methods: The study involved 14 athletes with hearing deprivation of varying degrees, aged 20 to 35 years (mean age 29.20 ± 1.3 years), with different sports qualifications. When evaluating the indicators of a simple visual-motor reaction, the reaction time, the degree of its stability, the level of functional capabilities of the nervous system of athletes were determined. To determine manual asymmetry, M. Annette's questionnaire, motor tests (dynamometry, tests for the interlacing of hands and applause) were used, and the coefficient of the right hand was calculated. When detecting visual asymmetry, the Rosenbach test and the spyglass test were used. The ratio of the right eye was also calculated. Results: It was revealed that a third of the examined athletes have a symmetrical distribution of signs both in the visual and manual spheres, a significant dependence of which on sports titles was not found. The time of a simple visual-motor reaction in volleyball athletes with hearing deprivation was reduced. The stability of the reaction and the level of functional capabilities were within the normal range and had a significant dependence on the sports title and category. Conclusion: It was revealed that volleyball players with hearing impair ment form a special type of interhemispheric interaction, characterized by a more even distribution of functional activity between the right and left hemispheres, and in connection with this, a low level of development of manual and visual asymmetry.

28 Challenges to Lateralizing Visual Memory Dysfunction in TLE Patients

Objective:Neuropsychological assessment is an essential part of presurgical evaluation for epilepsy patients with refractory temporal lobe epilepsy. Evaluations assist in localizing and lateralizing epileptogenic focal points and identifying possible risks for cognitive decline following surgery. Researchers and clinicians consistently find that verbal memory dysfunction is an accurate indicator of left temporal lobe epilepsy (TLE) through verbal measures such as the CVLT-II. Although visual memory structures are assumed to be in the right (nondominant) hemisphere, visual memory assessments have not been reliable in identifying right TLE. It is hypothesized that assessments to test visual memory are confounded by verbal cueing to assist in visual learning. To account for this, researchers have identified that comparing verbal and visual score asymmetries does accurately differentiate left and right TLE patients. This study aimed to determine if verbalvisual asymmetry using the CVLT-II and BVMT-R accurately identifies left and right TLE relative weaknesses potentially associated with epileptogenic regions.Participants and Methods:As part of a pre-surgical neuropsychological evaluation, 37 well-characterized medically refractory TLE patients (18 right TLE; 19 left TLE) were administered the Brief Visuospatial Memory Test-Revised to evaluate visuospatial memory and the CVLT-II to evaluate verbal memory. A multivariate analysis of variance was used to compare RTLE and LTLE group performances on BVMT-R delay recall subscales, using T-scores. Then memory asymmetry scores were calculated by converting CVLT-II verbal delay memory scores to T-scores and subtracting BVMT-R delayed recall T-score from the verbal memory T-score. An independent samples t-test was used to compare asymmetry scores between the groups.Results:There were no significant differences between patients with RTLE and LTLE for BVMT-R Delay [F(2,34) = 0.11, p = .895]. There was not a significant difference when accounting for verbal-visual asymmetry (t (35) = 0.422, p = 0.675, d = 12.566) between left (M = -2.42, SD = 13.82) and right side (M = -4.17, SD = 11.09).Conclusions:The BVMT-R did not identify nondominant hemisphere dysfunction in this sample of 18 right TLE patients. Because visual memory performance did not inform lateralization, we investigated the usefulness of memory asymmetry. Inconsistent with our hypothesis, verbal-visual memory asymmetry scores did not differentiate RTLE from LTLE in this sample. These findings add to existing findings that the BVMT-R may not be able to identify visuospatial memory dysfunction in epilepsy. Additionally, these data indicate the inability to assess for visuospatial memory even when accounting for verbal abilities in epilepsy patients. Future research should consider alternate visuospatial measures for the evaluation of epilepsy patients.

Bilateral arm movements are coordinated via task-dependent negotiations between independent and codependent control, but not by a "coupling" control policy.

Prior research has shown that coordination of bilateral arm movements might be attributed to either control policies that minimize performance and control costs regardless of bilateral symmetry or by control coupling, which activates bilaterally homologous muscles as a single unit to achieve symmetric performance. We hypothesize that independent bimanual control (movements of one arm are performed without influence on the other) and codependent bimanual control (two arms are constrained to move together with high spatiotemporal symmetry) are two extremes on a coordination spectrum that can be negotiated to meet infinite variations in task demands. To better understand and distinguish between these views, we designed a task where minimization of either control costs or asymmetry would yield different patterns of coordination. Participants made bilateral reaches with a shared visual cursor to a midline target. We then covertly varied the gain contribution of either hand to the shared cursor's horizontal position. Across two experiments, we show that bilateral coordination retains high task-dependent sensitivity to subtle visual feedback gain asymmetries applied to the shared cursor. Specifically, we found a change from strong spatial covariation between hands during equal gains to more independent control during asymmetric gains, which occurred rapidly and with high specificity to the dimension of gain manipulation. Furthermore, the extent of spatial covariation was graded to the magnitude of perpendicular gain asymmetry between hands. These findings suggest coordination of bilateral arm movements flexibly maneuvers along a continuous coordination spectrum in a task-dependent manner that cannot be explained by bilateral control coupling.NEW & NOTEWORTHY Minimization of performance and control costs and efferent coupling between bilaterally homologous muscle groups have been separately hypothesized to describe patterns of bimanual coordination. Here, we address whether the mechanisms mediating independent and codependent control between limbs can be weighted for successful task performance. Using bilaterally asymmetric visuomotor gain perturbations, we show bimanual coordination can be characterized as a negotiation along a spectrum between extremes of independent and codependent control, but not efferent control coupling.

Emotion recognition, not attentional capture, drives visual search asymmetries to emotional expressions

Emotion recognition, not attentional capture, drives visual search asymmetries to emotional expressions

Überblick und Handlungsleitfaden bei visuellen Störungen im Zusammenhang mit Kiefer- und Haltungsstörungen

Purpose. The human system consists of various subsystems. These are anatomically and functionally connected and form a structural unit. As a result, disorders in one subsystem can also affect other subsystems and the human system as a whole. Material and Methods. Using literature review and practi- cal experience, an overview of visual disorders associated with jaw and posture disorders is presented. These are visual acuity differences, spherical and astigmatic anisometropia, and binocular disorders. Visual disorders may be primary or secondary. Therefore, to determine visual asymmetry, testing for visual acuity and ametropias, as well as for sym- metric eye movement, convergence, and binocular function are useful. Results. Visual disorders with jaw and postural disorders can be transmitted by disorders of the nerve pathways (afferent as well as efferent disorders), muscles and skeleton. Therefore, an interdisciplinary assessment/diagnosis and selection of care and appropriate management is important. Conclusion. Optometrists must recognize visual disorders as- sociated with postural disorders in order to provide thorough history and treatment. Keywords symmetry, asymmetry, jaw disorders, postural disorders, binocular disorders

Left–right asymmetry of the visual system in the scallop Nodipecten nodosus (Bivalvia: Pectinidae)

ABSTRACT Left–right asymmetries are consistent differences between the left and right sides and represent an intriguing feature of molluscan morphology. Interestingly, external asymmetries, such as inequivalve shells, are often coupled with lateralization in the nervous system, which often includes functional and structural specializations of the left or right sides. In the case of visual asymmetries, lateralized phenotypes frequently include left–right differences in eye position, structure and use. To investigate lateralization and visual asymmetries among bivalves, we examined the visual and nervous systems of the scallop Nodipecten nodosus. We characterized different eye morphologies in the species and determined eye-side frequencies. We also studied the anatomy of the nervous system, focusing on the parietovisceral ganglion (PVG). Our results reveal that the visual and nervous systems of the scallop N. nodosus comprise consistent left–right asymmetries: (1) a greater number of eyes on the left side, (2) increased size of the left PVG lateral lobe, (3) larger glomeruli in the left PVG lateral lobe and (4) radial pallial nerves associated with the left lateral lobe spaced more widely than the more compactly arranged pallial nerves associated with the right lateral lobe. In addition, eyes with a distinctive morphology, where the optic vesicle is rotated, are more frequent on the left side. Considering the habit of this species to rest on the right valve, we hypothesize that curved eyes might contribute to expanding the overall visual field. Even though bivalves are not typically considered in the literature on lateralization, accumulating evidence for scallops, as suggested by our results, indicates their potential to reveal novel patterns of visual asymmetry in benthic invertebrates.

O hand, where art thou? Mapping hand location across the visual field during common activities

Humans employ visually-guided actions during a myriad of daily activities. These ubiquitous but precise manual actions rely on synergistic work between eye and hand movements. During this close cooperation between hands and eyes, the hands persist in sight in a way which is unevenly distributed across our visual field. One common assertion is that most hand actions occur in the lower visual field (LVF) because the arms are anatomically lower than the head, and objects typically rest on waist-high table surfaces. While experimental work has shown that humans are more efficient at reaching for and grasping targets located below their visual midline (Goodale and Danckert, Exp Brain Res 137:303–308, 2001), there is almost no empirical data detailing where the hands lie in the visual fields during natural hand actions. To build a comprehensive picture of hand location during natural visually guided manual actions, we analyzed data from a large-scale open-access dataset containing 100 h of non-scripted manual object interactions during domestic kitchen tasks filmed from a head-mounted camera. We found a clear vertical visual asymmetry with hands located in the lower visual scene (LVS) in more than 70% of image frames, particularly in ipsilateral space. These findings provide the first direct evidence for the established assumption that hands spend more time in the lower than in the upper visual field (UVF). Further work is required to determine whether this LVF asymmetry differs across the lifespan, in different professions, and in clinical populations.

Comparing retinotopic maps of children and adults reveals a late-stage change in how V1 samples the visual field

Adult visual performance differs with angular location –it is better for stimuli along the horizontal than vertical, and lower than upper vertical meridian of the visual field. These perceptual asymmetries are paralleled by asymmetries in cortical surface area in primary visual cortex (V1). Children, unlike adults, have similar visual performance at the lower and upper vertical meridian. Do children have similar V1 surface area representing the upper and lower vertical meridian? Using MRI, we measure the surface area of retinotopic maps (V1-V3) in children and adults. Many features of the maps are similar between groups, including greater V1 surface area for the horizontal than vertical meridian. However, unlike adults, children have a similar amount of V1 surface area representing the lower and upper vertical meridian. These data reveal a late-stage change in V1 organization that may relate to the emergence of the visual performance asymmetry along the vertical meridian by adulthood.

Effect of visual field asymmetries on performance while utilizing aircraft attitude symbology

This research explores the effect of symbology placement on human performance for users of head-mounted augmented reality displays. A pair of experiments examined the impact on visual performance asymmetries when perceiving complex, meaningful visual stimuli, such as the Arc Segment Attitude Reference (ASAR). The ASAR symbology represents an aircraft’s vertical flight path and roll angles. Experiment 1 examined participants’ performance in making categorical and coordinate judgments regarding various attitudes of the ASAR and a Gabor patch which were briefly presented in the peripheral visual field. The results were consistent with the horizontal-vertical anisotropy literature, which implies that performance would be better for stimuli placed on the horizontal than the vertical meridian. Experiment 2 assessed asymmetries for continuously presented stimuli in a dual-task environment which involved a centrally located, demanding visual psychomotor task and monitoring of the ASAR or Gabor stimuli at the same peripheral locations as Experiment 1. No performance differences were found as a function of peripheral stimulus placement. However, eye tracking, particularly for a subset of the participants suggest they employed a more efficient visual process to monitor the peripheral stimuli when the stimuli were placed on the horizontal meridian.

Influence of functional asymmetry on performance of technical actions at freestyle wrestlers

Purpose: to reveal the influence of functional asymmetry on the performance of technical actions in freestyle wrestlers. Material and methods. Analysis of scientific and methodical literature and Internet sources; pedagogical testing; pedagogical experiment; methods of mathematical statistics. The profile of functional asymmetry of the brain in freestyle wrestlers was determined. We used the tapping test by E. Ilyin, tests to determine motor and visual asymmetry and dynamometry. According to the results of the tapping test, E. Ilyin, the coefficient of functional asymmetry was calculated based on the working capacity of the left and right hands. 24 freestyle wrestlers aged 18-21 took part in the study. Results: during the previous study it was found that wrestlers mainly perform technical actions in one direction. A sportsman at the initial stage of training must learn techniques in both directions. However, at the stage of maximum realization of individual capabilities this rule should not always be observed. Since the majority of respondents suggested that in order to improve sports results it is necessary to strengthen the asymmetry of the wrestler, a set of special exercises was applied in the experimental group. In the given complex the accentuated performance of basic technical actions in a convenient way, individual dosage of exercises on development of flexibility, force, and also static endurance on the leading side was provided. After conducting the pedagogical experiment, we again conducted educational and training matches and analyzed them according to the indicators that were interesting to us. Having processed the results obtained after conducting the pedagogical experiment, we reached the following conclusions. In the control group, the increase in results for all indicators was: «right-handed people to the right» - 4,4 %; «right-handed to the left» - 0,8 %; «left-handed to the right» - 3,9 %; «left-handed to the left» - 10,9 %. In the experimental group, according to the same indicators, we observed the following increase in results: «right-handed to the right» - 13,5 %; «right-handed to the left» - 0,4 %; «left-handed to the right» - 0,5 %; «left-handed to the left» - 18,7 %. The conducted statistical processing made it possible to establish that there was a reliable increase in technical actions in the convenient direction for both right-handed and left-handed players. Summarizing the results of the pedagogical experiment, we can come to the conclusion that the use of a set of exercises embedded in the accented execution of technical processes in the leading direction contributes to the increase in results and the increase in the efficiency of the execution of technical processes. Conclusions. The analysis of the distribution of the individual profile of functional asymmetry in freestyle wrestlers showed that among the 24 wrestlers we studied aged 18-21 years, the right-sided profile of functional asymmetry predominates – 66 % of wrestlers, the left-sided profile of functional asymmetry has 20 % of wrestlers, the rest 14 % are ambidexters. The presence of a connection between the performance of a technical action and the profile of functional asymmetry in wrestlers was revealed: athletes perform technical actions in the leading direction more often and more efficiently. The use of a complex of exercises aimed at increasing asymmetry contributes to the growth of technical processes, and more pronounced in the leading direction. Thus, the increase in the control group «right-handed to the right» was 4,4 %, «left-handed to the left» - 10,9 %, in the experimental group – 13,5 % and 18,7 %, respectively.

Publication bias in pharmacogenetics of adverse reaction to antiseizure drugs: An umbrella review and a meta-epidemiological study.

Publication bias may lead to a misestimation in the association between pharmacogenetic biomarkers (PGx) and antiseizure drug's adverse effects (AEs). We aimed to assess its prevalence in this field. We searched for systematic reviews assessing PGx of antiseizure drug's AEs. For each unique association between a PGx, a drug and its AE, we used the available odds ratio (ORs) to generate corresponding funnel plots. We estimated the prevalence of publication bias using visual inspections and asymmetry tests. We explored the impact of publication bias using ORs adjusted for potential publication bias. Twenty-two associations were available. Our visual analysis suggested a publication bias in five out twenty-two funnel plots (23% [95%CI: 8; 45]). The Egger's test showed a significant publication bias in one (HLA-B*15:02 and phenytoin-induced Stevens-Johnson syndrome or toxic epidermal necrolysis, p = 0.03) out of nine (11% [95%CI: 0; 48]) and the Begg's test in one (HLA-B*15:02 and carbamazepine-induced serious cutaneous reactions, p = 0.02) out of ten (10% [95%CI: 0; 45]) assessable funnel plots. Adjusting for publication bias may reduce by half the ORs of the pharmacogenetics associations. Publication bias in the pharmacogenetic of antiseizure drug's AEs is not uncommon and may affect the estimation of the effect of such biomarkers. When conducting pharmacogenetic studies, it is critical to publish also the negative one.

Can a saliency model using feature sets derived cityscapes predict cultural differences in visual search asymmetry?

Can a saliency model using feature sets derived cityscapes predict cultural differences in visual search asymmetry?

Visual search asymmetries are explained by visual homogeneity

Visual search asymmetries are explained by visual homogeneity

ODP252 Urosepsis and Sodium-Glucose Co-Transporter-2 Inhibitors: A Systematic Review and Meta-Analysis

Abstract Objective Sodium-glucose cotransporter-2 (SGLT2) inhibitors are very effective in reducing hemoglobin A1c. They also have benefits in reducing cardiovascular events, heart failure hospitalization, and progression of renal disease in patients with and without T2DM. However, FDA issued a warning for a possible severe UTI. Conversely, the evidence from randomized clinical trials and observational studies is limited and controversial. Therefore, we aimed to investigate the association of urosepsis and SGLT-2 inhibitors using the method of systematic review and meta-analysis. Methods Potentially eligible studies were identified from MEDLINE, Scopus, EMBASE, Ovid, and the Cochrane Library from inception to September 2020 with the help of an experienced librarian aiming to identify studies reporting the number of adults users of any SGLT2 inhibitor (canagliflozin, dapagliflozin, empagliflozin, ertugliflozin, ipragliflozin, luseogliflozin, remogliflozin, and tofogliflozin) who developed urosepsis, compared to those who never used SGLT2 inhibitors. The following exclusion criteria were used: only abstracts or pilot data, studies reporting rates of urosepsis only in SGLT2 inhibitors users without comparison, or studies with a comparison group in which SGLT2 was not the only differential treatment. Results In total, 1203 papers were identified with our search strategies, of which 169 were evaluated as full text, and 6 studies were finally selected for the meta-analysis after two rounds of the independent review by five investigators. The overall risk of bias of the included studies was low-to-moderate. We found no difference in the risk of urosepsis in users of SGLT2 inhibitors (OR= 1.34; 95% CI, 0.79 to 2.28; P=0.28; I2=48%) compared to the comparison group. In a subgroup analysis by the type of SGLT2 inhibitor evaluated we found no differences between dapagliflozin (OR= 0.92; 95% CI, 0.51 to 1.67; P=0.82; I2=0%) or canagliflozin (OR= 0.32; 95% CI, 0. 03 to 3.63; P=0.27; I2=17%) users in the risk of urosepsis. Publication bias was assessed by performing funnel plots which showed visual asymmetry suggestion potential publication bias. Discussion/Conclusion In this systematic review and meta-analysis, including 6 publications and 456301 participants, we found that individuals treated with SGLT2 inhibitors do not have a significantly higher risk of urosepsis than individuals of the comparison group. Additionally, no differences were found in the risk of urosepsis when each SLGT2 inhibitor agent was assessed separately. Presentation: No date and time listed

Asymmetric visual representation of sex from facial appearance

We efficiently infer others’ traits from their faces, and these inferences powerfully shape our social behaviour. Here, we investigated how sex is represented in facial appearance. Based on previous findings from sex-judgment tasks, we hypothesized that the perceptual encoding of sex is not balanced but rather polarized: for the processes that generate a sex percept, the default output is “male,” and the representation of female faces extends that of the male, engaging activity over unique detectors that are not activated by male faces. We tested this hypothesis with the logic of Treisman’s studies of visual search asymmetries, predicting that observers should more readily detect the presence of female faces amongst male distractors than vice versa. Across three experiments (N = 32 each), each using different face stimuli, we confirmed this prediction in response time and sensitivity measures. We apply GIST analyses to the face stimuli to exclude that the search asymmetry is explained by differences in image homogeneity. These findings demonstrate a property of the coding that links facial appearance with a significant social trait: the female face is coded as an extension of a male default. We offer a mechanistic description of perceptual detectors to account for our findings and posit that the origins of this polarized coding scheme are an outcome of biased early developmental experience.

"Prefrontal" Neuronal Foundations of Visual Asymmetries in Pigeons.

This study was conducted in order to reveal the possibly lateralized processes in the avian nidopallium caudolaterale (NCL), a functional analogue to the mammalian prefrontal cortex, during a color discrimination task. Pigeons are known to be visually lateralized with a superiority of the left hemisphere/right eye for visual feature discriminations. While animals were working on a color discrimination task, we recorded single visuomotor neurons in left and right NCL. As expected, pigeons learned faster and responded more quickly when seeing the stimuli with their right eyes. Our electrophysiological recordings discovered several neuronal properties of NCL neurons that possibly contributed to this behavioral asymmetry. We found that the speed of stimulus encoding was identical between left and right NCL but action generation was different. Here, most left hemispheric NCL neurons reached their peak activities shortly before response execution. In contrast, the majority of right hemispheric neurons lagged behind and came too late to control the response. Thus, the left NCL dominated the animals’ behavior not by a higher efficacy of encoding, but by being faster in monopolizing the operant response. A further asymmetry concerned the hemisphere-specific integration of input from the contra- and ipsilateral eye. The left NCL was able to integrate and process visual input from the ipsilateral eye to a higher degree and thus achieved a more bilateral representation of two visual fields. We combine these novel findings with those from previous publications to come up with a working hypothesis that could explain how hemispheric asymmetries for visual feature discrimination in birds are realized by a sequential buildup of lateralized neuronal response properties in the avian forebrain.