Foreground/Background Manipulations Affect Presence

1995 ◽  
Vol 39 (21) ◽  
pp. 1410-1414 ◽  
Author(s):  
Jerrold D. Prothero ◽  
Hunter G. Hoffman ◽  
Donald E. Parker ◽  
Thomas A. Furness ◽  
Maxwell J. Wells
Keyword(s):  
Experimental Design ◽  
Visual Scene ◽  
Visual Environment ◽  
Double Blind ◽  
Pursuit Game ◽  
Virtual Visual Environment ◽  
Visual Scenes

A possible relation between vection and presence is discussed. Two experiments examined the hypothesis that “presence” is enhanced by manipulations which facilitate interpreting visual scenes as “background.” A total of 39 participants in two experiments engaged in a pursuit game while in a virtual visual environment generated by an HMD and rated their experience of “presence” on 5 questions. Experiment 1 compared two viewing conditions: visual scene masking at the eye and a paper mask mounted on the screen with the same 60° FOV, and showed that presence was enhanced by eye masking relative to screen masking. Experiment 2 replicated these findings with a double-blind experimental design.

scholarly journals The Language of Vision*

Perception ◽  
2021 ◽  
pp. 030100662199149
Author(s):  
Patrick Cavanagh
Keyword(s):  
Visual System ◽  
Language Planning ◽  
Spoken Language ◽  
Visual Language ◽  
Visual Scene ◽  
Visual Environment ◽  
Acquisition Process ◽  
Visual Processes ◽  
First Pass

The descriptions of surfaces, objects, and events computed by visual processes are not solely for consumption in the visual system but are meant to be passed on to other brain centers. Clearly, the description of the visual scene cannot be sent in its entirety, like a picture or movie, to other centers, as that would require that each of them have their own visual system to decode the description. Some very compressed, annotated, or labeled version must be constructed that can be passed on in a format that other centers—memory, language, planning—can understand. If this is a “visual language,” what is its grammar? In a first pass, we see, among other things, differences in processing of visual “nouns,” visual “verbs,” and visual “prepositions.” Then we look at recursion and errors of visual grammar. Finally, the possibility of a visual language also raises the question of the acquisition of its grammar from the visual environment and the chance that this acquisition process was borrowed and adapted for spoken language.

scholarly journals EXPRESS: Experimental Design of the EDIPHY (Effects of Dehydroepiandrosterone in Pulmonary Hypertension) Trial

2021 ◽  
pp. 204589402198955
Author(s):  
Thomas Patrick Walsh ◽  
Grayson Baird ◽  
Michael K Atalay ◽  
Saurabh Agarwal ◽  
Daniel Arcuri ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Pulmonary Hypertension ◽  
Experimental Design ◽  
Sex Hormone ◽  
Pulmonary Vascular Disease ◽  
Double Blind ◽  
Adrenal Steroid ◽  
Blood Institute ◽  
Post Menopausal ◽  
Rv Function

Pulmonary arterial hypertension (PAH) remains life-limiting despite numerous approved vasodilator therapies. Right ventricular (RV) function determines outcome in PAH but no treatments directly target RV adaptation. PAH is more common in women, yet women have better RV function and survival as compared to men with PAH. Lower levels of the adrenal steroid dehydroepiandrosterone (DHEA) and its sulfate ester are associated with more severe pulmonary vascular disease, worse RV function, and mortality independent of other sex hormones in men and women with PAH. DHEA has direct effects on nitric oxide (NO) and endothelin-1 (ET-1) synthesis and signaling, direct antihypertrophic effects on cardiomyocytes, and mitigates oxidative stress. EDIPHY (Effects of Dehydroepiandrosterone in Pulmonary Hypertension) is an on-going randomized double-blind placebo-controlled crossover trial of DHEA in men (n = 13) and pre- and post-menopausal women (n = 13) with Group 1 PAH funded by the National Heart, Lung and Blood Institute. We will determine whether orally administered DHEA 50 mg daily for 18 weeks affects RV longitudinal strain measured by cardiac magnetic resonance imaging, markers of RV remodeling and oxidative stress, NO and ET-1 signaling, sex hormone levels, other PAH intermediate end points, side effects and safety. The crossover design will elucidate sex-based phenotypes in PAH and whether active treatment with DHEA impacts NO and ET-1 biosynthesis. EDIPHY is the first clinical trial of an endogenous sex hormone in PAH. Herein we present the study’s rationale and experimental design.

scholarly journals Crossmodal Semantic Congruence Interacts with Object Contextual Consistency in Complex Visual Scenes to Enhance Short-Term Memory Performance

2021 ◽  
Vol 11 (9) ◽  
pp. 1206
Author(s):  
Erika Almadori ◽  
Serena Mastroberardino ◽  
Fabiano Botta ◽  
Riccardo Brunetti ◽  
Juan Lupiáñez ◽  
...  
Keyword(s):  
Short Term Memory ◽  
Memory Performance ◽  
Visual Stimuli ◽  
Spatial Position ◽  
Visual Scene ◽  
Facilitatory Effect ◽  
Short Term ◽  
Term Memory ◽  
Visual Scenes ◽  
Semantic Congruence

Object sounds can enhance the attentional selection and perceptual processing of semantically-related visual stimuli. However, it is currently unknown whether crossmodal semantic congruence also affects the post-perceptual stages of information processing, such as short-term memory (STM), and whether this effect is modulated by the object consistency with the background visual scene. In two experiments, participants viewed everyday visual scenes for 500 ms while listening to an object sound, which could either be semantically related to the object that served as the STM target at retrieval or not. This defined crossmodal semantically cued vs. uncued targets. The target was either in- or out-of-context with respect to the background visual scene. After a maintenance period of 2000 ms, the target was presented in isolation against a neutral background, in either the same or different spatial position as in the original scene. The participants judged the same vs. different position of the object and then provided a confidence judgment concerning the certainty of their response. The results revealed greater accuracy when judging the spatial position of targets paired with a semantically congruent object sound at encoding. This crossmodal facilitatory effect was modulated by whether the target object was in- or out-of-context with respect to the background scene, with out-of-context targets reducing the facilitatory effect of object sounds. Overall, these findings suggest that the presence of the object sound at encoding facilitated the selection and processing of the semantically related visual stimuli, but this effect depends on the semantic configuration of the visual scene.

scholarly journals Processing moving visual scenes during upright stance in elderly patients with mild cognitive impairment

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10363
Author(s):  
Martin Kucharik ◽  
Zuzana Kosutzka ◽  
Jozef Pucik ◽  
Michal Hajduk ◽  
Marian Saling
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Visual Stimulation ◽  
Center Of Pressure ◽  
Visual Scene ◽  
Upright Stance ◽  
Stimulus Period ◽  
Postural Responses ◽  
The Subject ◽  
Visual Scenes

Background The ability to maintain balance in an upright stance gradually worsens with age and is even more difficult for patients with cognitive disorders. Cognitive impairment plays a probable role in the worsening of stability. The purpose of this study was to expose subjects with mild cognitive impairment (MCI) and healthy, age-matched controls to moving visual scenes in order to examine their postural adaptation abilities. Methods We observed postural responses to moving visual stimulation while subjects stood on a force platform. The visual disturbance was created by interposing a moving picture in four directions (forward, backward, right, and left). The pre-stimulus (a static scene for 10 s), stimulus (a dynamic visual scene for 20 seconds) and post-stimulus (a static scene for 20 seconds) periods were evaluated. We separately analyzed the total path (TP) of the center of pressure (COP) and the root mean square (RMS) of the COP displacement in all four directions. Results We found differences in the TP of the COP during the post-stimulus period for all stimulus directions except in motion towards the subject (left p = 0.006, right p = 0.004, and away from the subject p = 0.009). Significant RMS differences between groups were also observed during the post-stimulus period in all directions except when directed towards the subject (left p = 0.002, right p = 0.007, and away from the subject p = 0.014). Conclusion Exposing subjects to a moving visual scene induced greater destabilization in MCI subjects compared to healthy elderly controls. Surprisingly, the moving visual scene also induced significant aftereffects in the MCI group. Our findings indicate that the MCI group had diminished adaptation to the dynamic visual scene and recovery. These results suggest that even mild cognitive deficits can impair sensory information integration and alter the sensory re-weighing process.

Evaluating online control of goal-directed arm movement while standing in virtual visual environment

2003 ◽  
Vol 14 (5) ◽  
pp. 253-260 ◽  
Author(s):  
Olivier Martin ◽  
Benjamin Julian ◽  
Laurence Boissieux ◽  
Jean-Dominique Gascuel ◽  
Claude Prablanc
Keyword(s):  
Arm Movement ◽  
Online Control ◽  
Visual Environment ◽  
Virtual Visual Environment

A Controlled Study of Lithium vs. Chlorpromazine in Acute Schizophrenics

1971 ◽  
Vol 119 (551) ◽  
pp. 435-440 ◽  
Author(s):  
Baron Shopsin ◽  
Suk Sik Kim ◽  
Samuel Gershon
Keyword(s):  
Treatment Outcome ◽  
Experimental Design ◽  
Lithium Carbonate ◽  
Thought Disorder ◽  
Controlled Study ◽  
Double Blind ◽  
Controlled Evaluation

A previous double-blind controlled evaluation of lithium and chlorpromazine in both manic and schizo-affective individuals carried out in this unit (Johnsonet al., 1968) indicated that 85 per cent of the schizo-affectives showed a worsening of thought disorder when treated with lithium carbonate, the majority developing symptoms of an acute brain syndrome. The possibility of experimental design accounting for such treatment outcome must be considered.

Human upright posture control in a virtual visual environment

2009 ◽  
Vol 35 (2) ◽  
pp. 177-182 ◽  
Author(s):  
B. N. Smetanin ◽  
G. V. Kozhina ◽  
A. K. Popov
Keyword(s):  
Posture Control ◽  
Visual Environment ◽  
Upright Posture ◽  
Virtual Visual Environment

scholarly journals The eyes of deep–sea fishes and the changing nature of visual scenes with depth

2000 ◽  
Vol 355 (1401) ◽  
pp. 1155-1159 ◽  
Author(s):  
Eric Warrant
Keyword(s):  
Point Source ◽  
Deep Sea ◽  
Point Sources ◽  
Visual Scene ◽  
Source Illumination ◽  
Extended Field ◽  
Visual Scenes

The visual scenes viewed by ocean animals change dramatically with depth. In the brighter epipelagic depths, daylight provides an extended field of illumination. In mesopelagic depths down to 1000 m the visual scene is semi–extended, with the downwelling daylight providing increasingly dim extended illumination with depth. In contrast, greater depths increase the prominence of point–source bioluminescent flashes. In bathypelagic depths (below 1000 m) daylight no longer penetrates, and the visual scene consists exclusively of point–source bioluminescent flashes. In this paper, I show that the eyes of fishes match this change from extended to point–source illumination, becoming increasingly foveate and spatially acute with increasing depth. A sharp fovea is optimal for localizing point sources. Quite contrary to their reputation as ‘degenerate’ and ‘regressed’, I show here that the remarkably prominent foveae and relatively large pupils of bathypelagic fishes give them excellent perception and localization of bioluminescent flashes up to a few tens of metres distant. In a world with almost no food, where fishes are weak and must swim very slowly, this range of detection (and interception) is energetically realistic, with distances greater than this physically beyond range. Larger and more sensitive eyes would give bathypelagic fishes little more than the useless ability to see flashes beyond reach.

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