Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Feedback control systems01:26

Feedback control systems

727
Feedback control systems are categorized in various ways based on their design, analysis, and signal types.
Linear feedback systems are theoretical models that simplify analysis and design. These systems operate under the principle that their output is directly proportional to their input within certain ranges. For instance, an amplifier in a control system behaves linearly as long as the input signal remains within a specific range. However, most physical systems exhibit inherent nonlinearity...
727
Summation Notation01:25

Summation Notation

253
Sigma notation, also known as summation notation, provides a concise method for representing the sum of a sequence of terms that follow a regular pattern. It utilizes the uppercase Greek letter sigma (∑), A typical expression is:In this form, k the index of summation is 1, the starting value, and n the ending value. The term ak​ represents the general term of the sequence.For example, the increasing sequence 5, 7, 9, ..., 23 over 10 terms can be expressed as:This simplifies the...
253
Feedback Inhibition00:46

Feedback Inhibition

57.2K
Biochemical reactions are occurring constantly in cells, converting starting substances to different products, usually with the help of enzymes that speed the reactions. Without enzymes, it would take far too long for most reactions to occur to be useful to the cell!
57.2K
Feedback Loops01:01

Feedback Loops

64.5K
In most cases, excessive hormone production is prevented by negative feedback—a loop that starts with a stimulus inducing the release of a particular substance, like a hormone, to maintain a certain level before triggering a signal that results in a decrease in further release of the hormone.
64.5K
Pulse amplitude and quality01:17

Pulse amplitude and quality

3.2K
Pulse amplitude is a crucial indicator of cardiac health because it provides valuable insights into the strength of left ventricular contractions and the overall uniformity of blood circulation within the vasculature. The strength of the pulse is directly related to the force with which the heart contracts and the volume of blood being pumped.
A weak or absent pulse may indicate reduced cardiac output or poor left ventricular contraction, which can be signs of cardiovascular dysfunction or...
3.2K
Effects of feedback01:24

Effects of feedback

1.0K
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...
1.0K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Parvalbumin-expressing interneurons improve sensory discrimination by shaping noise geometry in primate V1.

bioRxiv : the preprint server for biology·2026
Same author

Evaluation of the ROX index for predicting intubation in ICU patients.

International journal of medical informatics·2026
Same author

A Customizable 3D-Printed Neural Probe Array Using Two-Photon Polymerization with Millimeter-Scaled Conductive Polymer as an Electrode Material.

ACS applied materials & interfaces·2026
Same author

Laminar-specific control of response gain and orientation-tuning by parvalbumin-expressing inhibitory interneurons in primate visual cortex.

Research square·2026
Same author

Using an Adult-Designed Wearable for Pediatric Monitoring: Practical Tutorial and Application in School-Aged Children With Obesity.

Journal of medical Internet research·2026
Same author

Size tuning of neural response variability in laminar circuits of macaque primary visual cortex.

eLife·2026

Related Experiment Video

Updated: Feb 9, 2026

Control of Eating Behavior Using a Novel Feedback System
04:48

Control of Eating Behavior Using a Novel Feedback System

Published on: May 8, 2018

11.6K

Top-down feedback controls spatial summation and response amplitude in primate visual cortex.

Lauri Nurminen1, Sam Merlin1,2, Maryam Bijanzadeh1,3

  • 1Department of Ophthalmology and Visual Science, Moran Eye Institute, University of Utah, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.

Nature Communications
|June 13, 2018
PubMed
Summary
This summary is machine-generated.

Feedback connections from V2 to V1 alter neural responses, changing receptive field size and surround suppression. This research reveals feedback

More Related Videos

Force and Position Control in Humans - The Role of Augmented Feedback
06:31

Force and Position Control in Humans - The Role of Augmented Feedback

Published on: June 19, 2016

8.2K
Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
08:39

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator

Published on: January 28, 2019

10.4K

Related Experiment Videos

Last Updated: Feb 9, 2026

Control of Eating Behavior Using a Novel Feedback System
04:48

Control of Eating Behavior Using a Novel Feedback System

Published on: May 8, 2018

11.6K
Force and Position Control in Humans - The Role of Augmented Feedback
06:31

Force and Position Control in Humans - The Role of Augmented Feedback

Published on: June 19, 2016

8.2K
Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
08:39

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator

Published on: January 28, 2019

10.4K

Area of Science:

  • Neuroscience
  • Computational Neuroscience
  • Visual Processing

Background:

  • Sensory information flows hierarchically through cortical areas via feedforward and feedback connections.
  • Feedback's role in attention, expectation, and context is recognized, but its precise mechanisms remain unclear.
  • Understanding feedback mechanisms is crucial for deciphering complex sensory processing.

Purpose of the Study:

  • To investigate the causal role of feedback connections in modulating neural responses within the primary visual cortex (V1).
  • To elucidate how feedback from the secondary visual area (V2) influences receptive field properties and surround suppression in V1.
  • To explore the functional implications of V2 feedback on V1 neural activity.

Main Methods:

  • Optogenetic inactivation of feedback connections from V2 to V1 in primate models.
  • Recording neural responses in V1 before and after V2 feedback manipulation.
  • Analyzing changes in V1 receptive field size, response amplitude, and surround suppression.

Main Results:

  • Reducing V2 feedback significantly increased V1 receptive field size.
  • V1 cells showed decreased responses to stimuli within the receptive field and increased responses to stimuli in the surround.
  • Stronger V2 feedback reduction led to progressive increases in receptive field size and decreased response amplitude, consistent with network models.
  • Surround suppression in V1 was reduced by V2 feedback inactivation.

Conclusions:

  • Feedback connections from V2 play a critical role in shaping V1 receptive field size and surround suppression.
  • V2 feedback dynamically modulates V1 neural responses, influencing spatial summation and contrast gain control.
  • The findings suggest that V2 feedback mechanisms contribute to processes analogous to visual spatial attention.