Related Experiment Video
Updated: Jul 14, 2026
06:46
Investigating the Deployment of Visual Attention Before Accurate and Averaging Saccades via Eye Tracking and Assessment of Visual Sensitivity
Published on: March 18, 2019
Distortion of apparent shape of an object immediately before saccade
1Institute for Human Science and Biomedical Engineering, National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8566, Japan. h-sogo@aist.go.jp
Spatial Vision
|May 26, 2007
Summary
Perisaccadic mislocalization distorts perceived shape. A presented triangle
Area of Science:
- Neuroscience
- Visual Perception
- Psychophysics
Background:
- Perisaccadic mislocalization is a visual illusion where stimuli near saccade onset are misplaced.
- Its effect on the perceived shape of single objects remains largely unexamined.
Purpose of the Study:
- To investigate if perisaccadic mislocalization affects the perceived shape of a briefly presented triangle.
- To compare the shape distortion with the spatial mislocalization of a bar stimulus.
Main Methods:
- Participants viewed a triangle for 10 ms before a saccade.
- They reported the perceived slant direction relative to the saccade direction.
- Shape distortion was compared to perisaccadic bar mislocalization.
Main Results:
- The triangle's apparent shape was distorted in the direction opposite to the saccade.
- This distortion shared temporal and directional characteristics with bar mislocalization.
- The magnitude of shape distortion was less than bar mislocalization.
Conclusions:
- Perisaccadic mislocalization influences perceived object shape, not just location.
- Findings support models where spatial and shape distortions are linked during saccades.
Related Concept Videos
01:16Focusing of Light in the Eye
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
01:12Perceptual Constancy
Perceptual constancy is the ability to recognize that objects remain consistent and unchanged even when their appearance varies due to changes in sensory input. There are four main types of perceptual constancy: size constancy, shape constancy, color constancy, and brightness constancy.
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
01:15Depth Perception and Spatial Vision
Depth perception is the ability to perceive objects three-dimensionally. It relies on two types of cues: binocular and monocular. Binocular cues depend on the combination of images from both eyes and how the eyes work together. Since the eyes are in slightly different positions, each eye captures a slightly different image. This disparity between images, known as binocular disparity, helps the brain interpret depth. When the brain compares these images, it determines the distance to an object.
01:21Association Areas of the Cortex
Association areas are regions of the cerebral cortex that do not have a specific sensory or motor function. Instead, they integrate and interpret information from various sources to enable higher cognitive processes such as memory, learning, and decision-making. Some key association areas include the following:
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
01:12Visual Agnosia
Visual agnosia is a condition characterized by the inability to recognize visually presented objects despite having normal vision. For instance, a person with visual agnosia can describe the shape and color of an object but cannot identify or name it. This impairment does not affect their visual field, acuity, color vision, brightness discrimination, language, or memory. An example of this condition in a social setting is someone at a dinner party asking for "that silver thing with a round end"...
01:24Gyroscope: Precession
Precession can be demonstrated effectively through a spinning top. If a spinning top is placed on a flat surface near the surface of the Earth at a vertical angle and is not spinning, it will fall over due to the force of gravity producing a torque acting on its center of mass. However, if the top is spinning on its axis, it precesses about the vertical direction, rather than topple over due to this torque. Precessional motion is a combination of a steady circular motion of the axis and the...