Visual Stimuli for Space Perception in Vision

Overseen By Zijiang He, Ph.D.

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Louisville

Disqualifiers: Visual diseases, Movement restrictions, Pregnancy

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

180 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to understand how people perceive distance while moving, such as when walking or driving. Researchers will study how different visual scenes, known as "Visual Stimuli for Space Perception," affect people's ability to judge the location of surrounding objects. This knowledge could help in understanding how eye and brain issues might impact mobility and navigation. Individuals with normal or corrected vision and good 3D depth perception (stereo vision) might be suitable for this study. As an unphased trial, this study offers a unique opportunity to contribute to foundational research that could enhance understanding of mobility and navigation.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications.

What prior data suggests that this method is safe for studying visual space perception?

Research has shown that using visual images to study spatial understanding is generally safe, meaning people typically don't experience serious side effects. The University of Louisville is conducting a study to evaluate the effectiveness and ease of this method. The researchers aim to determine if visual images can enhance understanding of spatial perception during movement, potentially improving activities like walking and driving.

While specific data on side effects from these studies is lacking, visual images are commonly used in research without causing harm. As this study doesn't involve medication or invasive procedures, it is expected to be safe for participants. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Unlike standard treatments for vision and space perception issues, which often rely on corrective lenses or surgery, the Visual Stimuli for Space Perception approach is unique because it uses varied lighting in visual environments to directly measure and influence how individuals perceive space. This method has the potential to offer a non-invasive way to enhance spatial awareness by directly interacting with the brain's visual processing pathways, rather than just correcting physical issues with the eyes. Researchers are excited about this trial because it could lead to new insights into how visual cues can be manipulated to improve perception, potentially offering a novel avenue for managing visual perception disorders.

What evidence suggests that visual stimuli for space perception is effective for judging distance?

Research has shown that visual cues enhance understanding of depth and space. Each eye perceives a slightly different image, aiding in distance judgment. Studies have found that focusing on visual information improves processing and prioritization, making spatial awareness easier. This trial will test visual scenes by varying lit target locations in a visual environment and measuring subjects' perceived locations. Early findings suggest that observing visual scenes can enhance skills in perceiving the location of lit targets. Overall, the treatment aims to improve the ability to judge distances more effectively in real-life situations. ^{4 5 6 7 8}

Who Is on the Research Team?

Zijiang He, Ph.D.

Principal Investigator

University of Louisville

Are You a Good Fit for This Trial?

This trial is for adults and children over 18 with good stereo vision (sharp depth perception) and normal or corrected-to-normal eyesight. It's not suitable for those with physical movement issues, pregnant women due to the time needed, or anyone with a history of eye diseases.

Inclusion Criteria

I am 40 years old or younger.

My vision is 20/20, with or without correction.

Stereo acuity less than 20 arc sec

Exclusion Criteria

I have a history of eye problems.

I have limitations in my physical movements.

Vulnerable populations such as pregnant women will be excluded owing to the extensive time commitment required of the subjects.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Experimental Procedure

Participants judge perceived distances and heights of test targets before and after self-motion to assess visual space perception.

1 day

1 visit (in-person)

Follow-up

Participants are monitored for any changes in visual perception and cognitive processes after the experimental procedure.

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Visual Stimuli for Space Perception

Trial Overview The study tests how well people can judge the location of objects at intermediate distances while moving. Participants will be exposed to visual stimuli that challenge their space perception in a controlled three-dimensional environment.

How Is the Trial Designed?

Group I: Visual scences Experimental Treatment 1 Intervention

Lit target locations in visual environment will be varied and subjects' perceived locations will be measured.

Who Is Running the Clinical Trial?

University of Louisville

Lead Sponsor

Trials

353

Recruited

76,400+

National Eye Institute (NEI)

Collaborator

Trials

572

Recruited

1,320,000+

Published Research Related to This Trial

A novel binocular stimulus was created that lacks traditional disparity but includes an unmatched vertical sliver, which helps indicate depth discontinuities, demonstrating how our visual system can interpret depth cues without classical disparity.

Depth-discrimination performance was closely aligned for stimuli with unmatched features and those with classical binocular disparity, suggesting that both types of cues are processed similarly in human stereopsis, even across varying viewing durations.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The stereoscopic sliver: a comparison of duration thresholds for fully stereoscopic and unmatched versions. Sachtler, WL., Gillam, B.[2019]

The study reveals that the perception of spatial intervals, like the distance between two points, is influenced by the orientation of the stimulus in the retinal image, rather than just its physical length.

Using a laser range scanner to analyze natural images, the researchers found that the perceived length of an interval correlates with its orientation, suggesting that our visual perception is shaped by the statistical relationship between retinal projections and their real-world sources.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Range image statistics can explain the anomalous perception of length. Howe, CQ., Purves, D.[2018]

Perceived distance can vary significantly depending on the environmental context, challenging the assumption that distance perception is consistent in full-cue settings.

In five experiments involving both indoor and outdoor environments, researchers found that perceived distances were affected by the surrounding space, even when depth-related variables were kept constant.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Seeing beyond the target: environmental context affects distance perception. Witt, JK., Stefanucci, JK., Riener, CR., et al.[2017]

In a study with 32 Taiwanese university students, it was found that increasing the spacing between standard and comparison stimuli led to greater errors in depth perception, indicating that spatial relationships significantly impact visual accuracy.

The color of the light also influenced depth perception, with green light causing more errors compared to white, yellow, and red lights, while viewing distance affected accuracy, with the least errors occurring at 110 cm compared to shorter and longer distances.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of colored lights, spacing between stimuli, and viewing distance on error in a depth-matching task. Huang, KC.[2019]

Perceived depth significantly enhances the precision of visual judgments, with size discrimination being more accurate for objects perceived as closer to the observer, as shown in a series of experiments.

This 'close advantage' extends beyond basic tasks, improving performance in more complex perceptual tasks like face perception, indicating that depth perception plays a crucial role in various visual processing scenarios.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Perceived depth modulates perceptual resolution. Ahsan, T., Bolton, K., Wilcox, LM., et al.[2022]

Human perception of three-dimensional structures is systematically distorted, indicating that the relationship between physical and perceived space is noneuclidean.

Different sources of optical information, such as motion and stereo, reveal that perceived depth intervals are scaled differently compared to horizontal or vertical intervals, suggesting that our visual system processes depth in a unique way.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Distortions of three-dimensional space in the perceptual analysis of motion and stereo. Todd, JT., Tittle, JS., Norman, JF.[2017]

The perspective space model effectively transforms physical space into a visual perception framework, predicting how we perceive angles, distances, and sizes based on the distance of the vanishing point.

This model unifies various existing theories of distance and size perception, showing that both hyperbolic and power functions can describe perceived distance and size equivalently within certain experimental ranges.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Perspective Space as a Model for Distance and Size Perception. Erkelens, CJ.[2020]

Participants were able to perceive distance effectively with just 9-ms glimpses of targets, indicating that even very brief viewing can provide useful distance information in real-world environments.

However, sensitivity to distance perception decreased significantly when targets were at eye level and angular size was not informative, suggesting that the context and type of visual cues are crucial for accurate distance estimation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

From the most fleeting of glimpses: on the time course for the extraction of distance information. Gajewski, DA., Philbeck, JW., Pothier, S., et al.[2021]

Distance judgments for floor-level objects can be made more accurately when multiple objects are present, as the relative positions provide additional information, regardless of the viewing duration.

Older observers benefit from prior visual experience, as longer viewing times in earlier trials help improve their ability to judge distances in subsequent, shorter trials.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Effects of Age and Set Size on the Fast Extraction of Egocentric Distance. Gajewski, DA., Wallin, CP., Philbeck, JW.[2020]

Citations

1. withpower.com withpower.com/trial/phase-vision-8-2021-eb022

Visual Stimuli for Space Perception in Vision This treatment is unique because it uses visual stimuli to enhance depth perception and spatial awareness by exploiting both classical binocular disparity and ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6170011/

How visual spatial attention alters perception - PMC Visual attention is essential for visual perception. Spatial attention allows us to grant priority in processing and selectively process information at a given ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC12326128/

Unraveling Audiovisual Perception Across Space and Time Accurate perception of audiovisual stimuli depends crucially on the spatial and temporal properties of each sensory component, with multisensory ...

4. sciencedirect.com sciencedirect.com/topics/psychology/space-perception

Space Perception - an overview Space perception is defined as the ability to perceive the relative distances of objects and the absolute distance from an object to the observer.

5. researchgate.net researchgate.net/publication/21723471_Visual_Space_Perception_and_Visually_Directed_Action

(PDF) Visual Space Perception and Visually Directed Action The results of two types of experiments are reported. In 1 type, Ss matched depth intervals on the ground plane that appeared equal to frontal intervals at the ...

6. britannica.com britannica.com/science/space-perception

Space perception | Visual & Cognitive Effects Visual stimuli most likely dominate human perception of space because vision is a distance sense; it can supply information from extremely distant points in ...

7. miota.org miota.org/docs/Assessment_and_Intervention_of_Visual_Perception_and_Cognition3.pdf

Assessment and Intervention of Visual Perception and ... Visual Perception is the ability to interpret, understand, and define incoming visual information. Form Constancy is the ability to identify objects despite ...

8. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3448564/

Are impairments in visual-spatial attention a critical factor for ... Here we examined whether visual-spatial attention may be a core neuro-cognitive system showing abnormal function in fallers.