Related Experiment Video
Updated: Jun 8, 2026
05:07
Using Looming Visual Stimuli to Evaluate Mouse Vision
Published on: June 13, 2019
The functional roles of feedback projections in the visual system
1Vision Research Laboratory, Center for Brain Science Research and School of Life Sciences, Fudan University, Shanghai 200433, China. tdshou@fudan.edu.cn
Neuroscience Bulletin
|October 1, 2010
Summary
Feedback projections in the visual system are crucial for attention, searching, and cognition. This review explores their lesser-understood functional roles in complex neural networks.
Area of Science:
- Neuroscience
- Visual System Research
- Neural Circuitry
Background:
- Neurons form complex networks via feedforward, feedback, and lateral projections.
- The functional roles of feedback projections are less understood than feedforward pathways.
- The visual cortex serves as a model for studying cortical feedback functions.
Purpose of the Study:
- To review the functional roles of feedback projections within the visual system.
- To highlight the importance of feedback in higher cognitive functions mediated by the visual cortex.
Main Methods:
- Literature review of studies on visual system feedback.
- Analysis of research on attention, searching, and cognition related to visual feedback.
Main Results:
- Feedback projections significantly contribute to visual attention and target searching.
- Cortical feedback plays a role in cognitive processes within the visual system.
- Understanding feedback is key to deciphering complex visual information processing.
Conclusions:
- Feedback projections are integral to visual processing and cognitive functions.
- Further research into visual feedback mechanisms is warranted.
- This review consolidates current knowledge on the functional significance of feedback in the visual system.
Related Concept Videos
01:24Vision
Vision is the result of light being detected and transduced into neural signals by the retina of the eye. This information is then further analyzed and interpreted by the brain. First, light enters the front of the eye and is focused by the cornea and lens onto the retina—a thin sheet of neural tissue lining the back of the eye. Because of refraction through the convex lens of the eye, images are projected onto the retina upside-down and reversed.
01:26Visual System
Light enters the eye through the cornea, a transparent, dome-shaped surface covering the surface of the eyeball that helps to direct and focus incoming light. This light is then channeled toward the pupil, an adjustable opening whose size is controlled by the iris. The iris, a pigmented muscle, regulates the amount of light entering the eye by contracting or dilating the pupil, thereby ensuring optimal light levels for clear vision.
Once through the pupil, the light passes through the lens, a...
Once through the pupil, the light passes through the lens, a...
01:20Anatomy of the Eyeball
The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle layer, the vascular tunic,...
01:32The Retina
The retina is a layer of nervous tissue at the back of the eye that transduces light into neural signals. This process, called phototransduction, is carried out by rod and cone photoreceptor cells in the back of the retina.
01:24Effects of feedback
Feedback in control systems plays a critical role in shaping various operational parameters, extending beyond simple error reduction to influence stability, bandwidth, gain, impedance, and sensitivity. Understanding these effects requires examining a basic feedback system characterized by defined input, output, error, and feedback signals.
Feedback significantly modifies the gain of a control system. The gain of a system without feedback is altered by a factor of one plus GH, where G represents...
Feedback significantly modifies the gain of a control system. The gain of a system without feedback is altered by a factor of one plus GH, where G represents...
01:14Motor and Sensory Areas of the Cortex
The cerebral cortex, the brain's outermost layer, is pivotal in processing complex cognitive tasks, emotions, and various sensory inputs and executing voluntary motor activities. This intricate structure is divided into three primary functional areas: the motor areas, sensory areas, and association areas.
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex.
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex.