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2021 ◽  
Vol 2 (2) ◽  
pp. 187-209
Author(s):  
Mamoona Khan

Creative brains are kept only by sensitive creatures, and the most empathetic are of those associated with visual arts fields, affected even by a minor stir in their surroundings, which is reflected in their creative endeavours. They sub consciously interpret their time. Unpleasantness of war or situations analogous to war have always left a negative mark on their aesthetic interpretations.  History is replete with such examples. But the most stunningly heinous transgressions were exercised by modern mechanisms of war that violated ethics par human perception. The era shattered beliefs of man on humanitarian values. It also caused transformation in the field of aesthetics which is beyond human comprehension. The metamorphosis was so rapid that it brought aesthetics and beauty at antithetical stages, which led the French artist Paul Duchamp to display a urinal as a piece of sculpture in an art exhibition. Hence, weirdness replaced beauty; logical delineations substituted the abstruse, and crafty ousted the artistic, still protected under the umbrella of art. It is labelled as modern, subjective or abstract but not viewed as a repercussion of war trauma. The paper will be exploratory research to probe reasons behind the apparently unreasoned transformations delineated through art. Modern art specimens of post-war era along with those resulted from a few chaotic situations will be analysed to draw conclusions. It will be based on deductive methods of reasoning to scrutinise history, psychology and the field of art in order to comprehend the impact and reactions of war trauma on sensitive souls of artists that led them to transform the entire visual field of aesthetics. 


2021 ◽  
Author(s):  
Rui Costa ◽  
Pedro Campos ◽  
Madalena Wiborg ◽  
Catarina Rebôlo ◽  
Marc Wittmann ◽  
...  

Visual snow is a condition of unclear prevalence characterized by tiny flickering dots throughout the entire visual field. It appears to result from visual cortex hyperactivity and possibly correlates with propensity to be engrossed in sensory and imaginary experiences (absorption). The prevalence and correlates of visual snow, and emotional reactions to it, were explored in the general Portuguese population with three studies with online surveys. In Study 1, 564 participants were shown an animated graphic simulation of visual snow and asked to rate how frequently they see it on a scale anchored by 0% and 100% of the time. They also reported their degree of distress and fascination resulting from visual snow. Absorption was measured with the Modified Tellegen Absorption Scale. 44% of respondents reported they see visual snow at least 10% of the time, and 20% reported seeing it between 80% and 100% of the time. Similar to findings in clinical samples, the frequency of visual snow correlated with tinnitus frequency, migraine, and entoptic phenomena, but not with ophthalmologic problems. It was confirmed that visual snow is related to absorption. Although distress caused by visual snow was generally absent or minimal, a substantial minority (28%) reported moderate to high levels of distress. High fascination with visual snow was reported by 9%. In Studies 2 and 3, visual snow was measured by means of verbal descriptions without graphic simulation (“visual field full of tiny dots of light” and “world seen with many dots of light”, respectively). The results were similar to those in Study 1, but seeing visual snow 80%-100% of the time was less frequent (6.5% in Study 2 and 3.6% in Study 3). Visual snow has been insufficiently investigated. More research is needed to uncover underlying neurophysiological mechanisms and psychological and behavioral correlates.


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Florian Alexander Dehmelt ◽  
Rebecca Meier ◽  
Julian Hinz ◽  
Takeshi Yoshimatsu ◽  
Clara A Simacek ◽  
...  

Many animals have large visual fields, and sensory circuits may sample those regions of visual space most relevant to behaviours such as gaze stabilisation and hunting. Despite this, relatively small displays are often used in vision neuroscience. To sample stimulus locations across most of the visual field, we built a spherical stimulus arena with 14,848 independently controllable LEDs. We measured the optokinetic response gain of immobilised zebrafish larvae to stimuli of different steradian size and visual field locations. We find that the two eyes are less yoked than previously thought and that spatial frequency tuning is similar across visual field positions. However, zebrafish react most strongly to lateral, nearly equatorial stimuli, consistent with previously reported spatial densities of red, green and blue photoreceptors. Upside-down experiments suggest further extra-retinal processing. Our results demonstrate that motion vision circuits in zebrafish are anisotropic, and preferentially monitor areas with putative behavioural relevance.


2021 ◽  
pp. 1-40
Author(s):  
Katharina Margareta Theresa Pöhlmann ◽  
Julia Föcker ◽  
Patrick Dickinson ◽  
Adrian Parke ◽  
Louise O’Hare

Abstract Virtual Reality (VR) experienced through head-mounted displays often leads to vection, discomfort and sway in the user. This study investigated the effect of motion direction and eccentricity on these three phenomena using optic flow patterns displayed using the Valve Index. Visual motion stimuli were presented in the centre, periphery or far periphery and moved either in depth (back and forth) or laterally (left and right). Overall vection was stronger for motion in depth compared to lateral motion. Additionally, eccentricity primarily affected stimuli moving in depth with stronger vection for more peripherally presented motion patterns compared to more central ones. Motion direction affected the various aspects of VR sickness differently and modulated the effect of eccentricity on VR sickness. For stimuli moving in depth far peripheral presentation caused more discomfort, whereas for lateral motion the central stimuli caused more discomfort. Stimuli moving in depth led to more head movements in the anterior–posterior direction when the entire visual field was stimulated. Observers demonstrated more head movements in the anterior–posterior direction compared to the medio-lateral direction throughout the entire experiment independent of motion direction or eccentricity of the presented moving stimulus. Head movements were elicited on the same plane as the moving stimulus only for stimuli moving in depth covering the entire visual field. A correlation showed a positive relationship between dizziness and vection duration and between general discomfort and sway. Identifying where in the visual field motion presented to an individual causes the least amount of VR sickness without losing vection and presence can guide development for Virtual Reality games, training and treatment programmes.


Cephalalgia ◽  
2021 ◽  
pp. 033310242098544
Author(s):  
Teresa Catarci

Background Persistent migraine with aura and neuroimaging examinations revealing ischaemia in the contralateral cortex may be associated with migrainous infarction. Despite being a neurological symptom that is distinct from migraine with aura, the visual snow phenomenon may also be associated with cerebral ischaemia. Here we describe a patient who reported short-lasting daily symptoms of visual snow that affected his entire visual field before becoming continuous and left-sided following acute occipital brain ischaemia. Case report In February 2017, a 74-year-old retired male was referred to our headache outpatient clinic with a diagnosis of recent right occipital cerebral ischaemia and migraine with aura. The patient reported visual snow symptoms that had changed from being bilateral and temporary to left-sided and permanent one day upon awakening; after being admitted to hospital a few hours later, he discovered he had had a stroke. He said he had never had any symptoms of migraine with aura. The visual snow phenomenon disappeared completely after about 1 year. Conclusions In our patient, a temporary daily visual snow phenomenon reversed to a persistent one. This phenomenon occurred in the part of his visual field that had been affected by the ischaemic occipital stroke, as typically happens in migrainous infarction. We hypothesise that the occipital lesion disrupted the inhibitory circuits, leading to a quadrantopic persistent visual snow. Since the mechanism may be the same as that observed in migrainous infarction, though with a different pathophysiology, it is possible to speculate that the aura in this case is the result, as opposed to the cause, of stroke in most patients.


Author(s):  
Gerrit L. J. Onderwater ◽  
Michel D. Ferrari

Visual snow is characterized by continuous visual disturbances in the form of countless tiny particles present in the entire visual field, often interpreted as television static. The visual disturbances are almost always accompanied by additional symptoms, including palinopsia, nyctalopia, photophobia, entoptic phenomenon, bilateral tinnitus, concentration problems, lethargy, and irritability. Visual snow has been linked to migraine and the migrainous aura. The clinical phenotype of visual snow clearly different from migraine; however, the co-occurrence with migraine (aura) might imply that both conditions share underlying pathophysiological mechanism(s). Visual snow is currently diagnosed on patient history alone, as additional investigations are typical normal and do not contribute to the diagnosis. However, ophthalmological investigation, neuroimaging, and, in selected cases, electroencephalography are recommend to rule out other disorders. Although self-limiting in some cases, visual snow typically remains a chronic condition that is very difficult to suppress with drug or non-pharmacological treatment.


2020 ◽  
Author(s):  
Vladislav Khvostov ◽  
Yuri Markov ◽  
Timothy F. Brady ◽  
Igor Utochkin

Many studies have shown that people can rapidly and efficiently categorize the animacy of individual objects and scenes, even with few visual features available. Does this necessarily mean that the visual system has an unlimited capacity to process animacy across the entire visual field? We tested this in an ensemble task requiring observers to judge the relative numerosity of animate vs. inanimate items in briefly presented sets of multiple objects. We generated a set of morphed “animacy continua” between pairs of animal and inanimate object silhouettes and tested them in both individual object categorization and ensemble enumeration. For the ensemble task, we manipulated the ratio between animate and inanimate items present in the display and we also presented two types of animacy distributions: “segmentable” (including only definitely animate and definitely inanimate items) or “non-segmentable” (middle-value, ambiguous morphs pictures were shown along with the definite “extremes”). Our results showed that observers failed to integrate animacy information from multiple items, as they showed very poor performance in the ensemble task and were not sensitive to the distribution type despite their categorization rate for individual objects being near 100%. A control condition using the same design with color as a category-defining dimension elicited both good individual object and ensemble categorization performance and a strong effect of the segmentability type. We conclude that good individual categorization does not necessarily allow people to build ensemble animacy representations, thus showing the limited capacity of animacy perception.


2020 ◽  
Vol 4 (1) ◽  
pp. 2514183X2092569
Author(s):  
Ozan Eren ◽  
Christoph J Schankin

Background: Patients with visual snow syndrome (VSS) describe tiny flickering dots in the entire visual field resembling the noise of a poorly adjusted channel of analogue television with additional symptoms. Little is known about the pathophysiology and therapeutic options for this debilitating condition. Objectives: We present a case series of three patients with VSS taking mirtazapine, one of the most often prescribed antidepressants, and discuss the utility of antidepressants by reviewing our current understanding of pathophysiology and therapy. Results: Mirtazapine has no effect on VSS, neither positive nor negative. This is in line with the reports from the literature suggested only some beneficial effects from lamotrigine. Conclusions: Since the pathophysiology of VSS is not fully understood, we still rely on the reports of individual cases or patient series. This includes not only the positive, but also the negative results to avoid unnecessary treatment trials. Looking into the literature, antidepressants do not seem to be a solution for the visual symptoms. So far, best data exists for the anticonvulsant lamotrigine.


2019 ◽  
pp. 249-254
Author(s):  
Kenneth J. Ciuffreda ◽  
MH Esther Han ◽  
Barry Tannen

Visual snow syndrome (VSS) is a relatively rare, unusual, and disturbing abnormal visual condition. The individual perceives “visual snow” (VS) throughout the entire visual field, as well as other abnormal visual phenomena (e.g., photopsia). Only relatively recently has treatment been proposed (e.g., chromatic filters) in adults with VSS, but rarely in the pediatric VSS population (i.e., medications). In this paper, we present three well-documented cases of VSS in children, including their successful neuro-optometric therapeutic interventions (i.e., chromatic filters and saccadic-based vision therapy)


Cephalalgia ◽  
2019 ◽  
Vol 40 (4) ◽  
pp. 393-398 ◽  
Author(s):  
Ozan E Eren ◽  
Ruth Ruscheweyh ◽  
Andreas Straube ◽  
Christoph J Schankin

Objective To quantify photophobia in visual snow syndrome (VSS), a debilitating migraine-associated visual disturbance manifesting with continuous “TV snow-like” flickering dots in the entire visual field and additional visual symptoms, such as photophobia. Methods Photophobia was compared between 19 patients with VSS and 19 controls matched for age, sex, migraine and aura using the Leiden Visual Sensitivity Scale (L-VISS). Results Patients with VSS had an increased L-VISS-score compared to matched controls [(22.2 ± 5.9 vs. 4.4 ± 4.8; ANOVA, factors VSS and comorbid migraine: Main effect for VSS (F = 100.70; p < 0.001), but not for migraine (F < 0.01; p = 1.00) or the interaction (F = 1.93; p = 0.16)]. An L-VISS-score of 14 identified VSS with a sensitivity and specificity of 95% (Receiver Operating Characteristic analysis, 0.986 ± 0.014, p ≤ 0.001). Conclusion Patients with VSS suffer continuously from photophobia at a level similar to chronic migraineurs during attacks. Although migraine and VSS share dysfunctional visual processing, patients with VSS might be more severely affected.


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