Summary: A recent study reveals how the brain makes up for quick eye movements while maintaining a steady sensory perception despite active visual input. This security mechanism malfunctions for non-rigid motion, such as rotating vortices, according to research findings, leading to physical instability.
Eye-tracking tests showed that rapid eye movements, or saccades, could n’t track these complex motions, challenging established visual processing models. This finding demonstrates that diverse neural pathways are followed by easy and quick eye movements.
These findings you advance research into cognitive and neurological disorders. The study provides a fresh perspective on the body’s action perception processes and vision stability.
Important Information:
- For non-rigid objects, like rotating vortices, the body’s normal physical security mechanism fails, resulting in physical disruptions.
- The existence of easy and quick eye movements is refuted by the idea that they act in the same way as movement signals.
- The development of the new concept of sensory stimulus may lead to advancements in neurodegenerative diseases by revealing changes in physical compensation mechanisms.
Origin: University of Munster
High efficiency from the brain is required for the sensory perception of visual stimuli.
More than ten million information is absorbed by the eyes every minute, and thousands of nerve fibers carry it to the brain. Yet though we are constantly moving our sight, this leads us to believe the universe is secure.
Experts believe that a long-term, unresolved specific compensation mechanism of the physical system contributed to this.
A study team led by University of Münster psychologist Prof. Markus Lappe has examined how a very active physical output signal on the retina causes this robust perception of the world.
They focussed on the movement view of non-rigid objects such as fireplace or liquid, which is almost unknown.
The researchers found that, contrary to previous assumptions, smooth eye movements ( smooth pursuit ) cannot be performed for all types of visual motion.
Additionally, they were able to demonstrate for the first time that certain non-rigid movement types are compensated for by the compensation mechanism for quick eye movements ( saccades ).
As a result, physical security is lost. The results of the study have been published in the journal  ,’Science Advances’.
Vision research has long held that similar motion signals cause quick and easy eye movements.
Our findings demonstrate that the two techniques are clearly separated. They run along various neuronal pathways and are essentially unique, explains Markus Lappe.
The researchers presented a recently discovered visible motion illusion in the research that causes a disruption to geographical perception. 15 people had to adopt a simulated spinning vortex with their eye as it moved through a field of dots to test the new trigger concept.
‘ Usually this is an easy process, and the sight remain fixed on the subject. So, they move continually at the rate of the object. However, the maelstrom could not be followed, so the eye remained stable for a period of time,’ explains PhD student Krischan Alexander Koerfer.
Every 400 milliseconds, the maelstrom returns to the center of the eye, causing a cycle of rapid vision movement. Each day the subjects made for an attention movement, the vortex seemed to leap ahead.
The typical compensation mechanism for quick eye movements malfunctioned when the swirl moved. The eye was unable to follow the resulting movement, despite what was plainly visible. This is a recently unfamiliar mixture.’
Methodology:
The analysis team used high-speed infrared cameras, or “eye tracker,” to accurately measure the eye position and movements synchronically while examining the relationship between the presented physical stimulation and the corresponding view, such as perceived jumps.
In this process, infrared light is used to illuminate the eyes, and the reflections on the cornea and pupil are captured and analyzed. The reflections help to determine the eye’s precise position and motion.
The recent findings from fundamental research are of particular benefit to cognitive and brain research.
The fact that a movement with a compensation mechanism failure is presented for the first time allows for the development of new models, says Markus Lappe.
The new stimulus concept can also be applied to the treatment and investigation of neurodegenerative diseases in the long run.
About this news about this research in visual neuroscience
Author: Kathrin Kottke
Source: University of Munster
Contact: Kathrin Kottke – University of Munster
Image: The image is credited to Neuroscience News
Original Research: Open access.
According to Markus Lappe and colleagues,” Inability to pursue non-rigid motion results in spatial perception instability.” Science Advances
Abstract
Stability of spatial perception is a result of the inability to follow non-rigid motion.
By combining retinal input with internal forecasts about the visual effects of eye movements, vision creates a stable representation of space. We report a non-rigid motion that causes visual instability and interferes with perception.
This motion is accurately perceived during fixation, but it cannot be pursued. Catch-up saccades are purposefully directed at moving targets, but each saccade causes the motion stimulus to veer off the map.
Our findings reveal four important things about perception and the visuomotor system: ( 1 ) Pursuit fails for some types of motion; ( 2 ) Pursuit and catch-up saccades are independently controlled; ( 3 ) Saccade prediction is independent of saccade control; and ( 3 ) Visual stability of moving objects depends on similar motion mechanisms as pursuit.
