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Adaptive Gain Modulation in V1 Explains Contextual Modifications during Bisection Learning

Roland Schäfer, Eleni Vasilaki, Walter Senn, Karl J. Friston
2009 PLoS Computational Biology  
The model reproduces both the psychophysical results on bisection learning and the modified contextual interactions observed in V1 during task performance.  ...  Perceptual learning mainly consists in strengthening this attentional signal, leading to a more effective gain modulation.  ...  Hence, the experimental data is more readily explained if the modulations of the contextual interactions in V1 originate from a task-dependent topdown signal to V1 which is adapted during perceptual learning  ... 
doi:10.1371/journal.pcbi.1000617 pmid:20019808 pmcid:PMC2788217 fatcat:wr4ojulep5gazbprgj4xqbptni

Perceptual Learning via Modification of Cortical Top-Down Signals

Roland Schäfer, Eleni Vasilaki, Walter Senn
2007 PLoS Computational Biology  
The classical view of perceptual learning is that practicing modulates the feedforward input stream through synaptic modifications onto or within V1.  ...  neuronal gain within V1.  ...  We show in a model that top-down modulation of V1 during unsupervised perceptual learning can suppress intrinsic nonlinearities in V1.  ... 
doi:10.1371/journal.pcbi.0030165 pmid:17715996 pmcid:PMC1950342 fatcat:6s4jj4meazcyfi2i2pylaaqxiu

Neural networks and perceptual learning

Misha Tsodyks, Charles Gilbert
2004 Nature  
Perceptual learning is the improvement in performance on a variety of simple sensory tasks, following practice.  ...  Second, it has to describe the changes that occur in the sensory pathways when perceptual learning occurs.  ...  These two modifications in tuning lead to opposite effects on the orientation discrimination at the trained or adapted orientation (improvement for learning and deterioration for adaptation).  ... 
doi:10.1038/nature03013 pmid:15483598 pmcid:PMC1201476 fatcat:hzp2zk3uozelhlstu3ttk55i2a

Brain States: Top-Down Influences in Sensory Processing

Charles D. Gilbert, Mariano Sigman
2007 Neuron  
top-down modulation.  ...  Instead, the effects can be of many different kinds, not only augmenting or multiplying responses but also sharpening tuning curves, controlling contextual influences, or acting as a modulator of plasticity  ...  The growing body of evidence points more toward the latter: whether one looks at how neurons in V1 carry information related to a three-line bisection task or how neurons in the frontal lobe modulate their  ... 
doi:10.1016/j.neuron.2007.05.019 pmid:17553419 fatcat:ylul43i5wbhx5ddza445jvewhi

Perceptual learning in visual hyperacuity: a reweighting model

Series Peggy
2009 Frontiers in Computational Neuroscience  
Our simulations also shed light on the model's limitations, for example in accounting for temporal aspects of training procedures or dependency of learning with contextual stimuli, which will need to be  ...  Improvements of visual hyperacuity are a key focus in research of perceptual learning.  ...  Their role is to remove contextual biases due to lateral interactions in V1, thus linearizing the representation, as well as to increase the gain of excitatory neurons.  ... 
doi:10.3389/conf.neuro.10.2009.14.166 fatcat:opulwxp7t5hwncbbgmpg7vtvyq

Perceptual learning in visual hyperacuity: A reweighting model

Grigorios Sotiropoulos, Aaron R. Seitz, Peggy Seriès
2011 Vision Research  
Our simulations also shed light on the model's limitations, for example in accounting for temporal aspects of training procedures or dependency of learning with contextual stimuli, which will need to be  ...  Improvements of visual hyperacuity are a key focus in research of perceptual learning.  ...  Their role is to remove contextual biases due to lateral interactions in V1, thus linearizing the representation, as well as to increase the gain of excitatory neurons.  ... 
doi:10.1016/j.visres.2011.02.004 pmid:21316384 fatcat:gduyg4bo7jeglfuaezv66tjg2m

Perceptual learning in Vision Research

Dov Sagi
2011 Vision Research  
The stability of the visual system is viewed as an adaptation to a stable environment and instances of perceptual learning as a reaction of the brain to abrupt changes in the environment.  ...  More recent studies during the last decade revealed the conditions needed for learning and the conditions under which learning can be generalized across stimuli and tasks.  ...  If all perceptual learning is overfitting, how much of the performance gain can be explained by it?  ... 
doi:10.1016/j.visres.2010.10.019 pmid:20974167 fatcat:ztpvx53nbfewzf3chvevxvum5q

Centralized Power Control in Cognitive Radio Networks Using Modulation and Coding Classification Feedback [article]

Anestis Tsakmalis, Symeon Chatzinotas, Björn Ottersten
2015 arXiv   pre-print
User (PU) operating based on an Adaptive Coding and Modulation (ACM) protocol.  ...  The learning process enabler is a cooperative Modulation and Coding Classification (MCC) technique which estimates the Modulation and Coding scheme (MCS) of the PU.  ...  In this point, we need to explain how channel learning in beamforming problems can easily be translated as IP U = g⊺ p (1) channel learning in  ... 
arXiv:1510.06634v1 fatcat:sa74jsg3lbedvdzeaoltflx37m

27th Annual Computational Neuroscience Meeting (CNS*2018): Part Two

2018 BMC Neuroscience  
P271 Predicting runway excitation in nonlinear Hawkes processes  ...  Results: For single-stage gain adaptation, we found that the effect on V1 tuning of prolonged adaptation to a single direction depended on the size of the adapting and test stimuli (drifting grating patches  ...  in gain.  ... 
doi:10.1186/s12868-018-0451-y fatcat:afgrjlnjgjarldkuwo3e2pt5sm

Does attention play a role in dynamic receptive field adaptation to changing acoustic salience in A1?

Jonathan B. Fritz, Mounya Elhilali, Stephen V. David, Shihab A. Shamma
2007 Hearing Research  
Acoustic filter properties of A1 neurons can dynamically adapt to stimulus statistics, classical conditioning, instrumental learning and the changing auditory attentional focus.  ...  They learned to generalize the task for a wide variety of distinct background and foreground target stimuli.  ...  They attribute this adaptive, dynamic multiplexing to a combination of changes in local circuits that arose during perceptual learning and top-down control that allows switching between the two different  ... 
doi:10.1016/j.heares.2007.01.009 pmid:17329048 pmcid:PMC2077083 fatcat:i5xzbmhkxbf77jfsb6jjiwgvde

Learning to see again: Biological constraints on cortical plasticity and the implications for sight restoration technologies [article]

Michael Beyeler, Ariel Rokem, Geoffrey M Boynton, Ione Fine
2017 bioRxiv   pre-print
We close by discussing what is known about brain plasticity in sight restoration patients and discuss biological mechanisms that might eventually be harnessed to improve visual learning in these patients  ...  Consequently, the ability to learn to make use of this abnormal retinal input plays a critical role in whether or not some functional vision is successfully regained.  ...  One possibility is that effects of learning for orientation within V1 are predominantly due to contextual modulation of extraclassical receptive field properties of V1 responses ) and/or modifications  ... 
doi:10.1101/115188 fatcat:5zlxuvtpwzbk3loesqfs2zd4eq

Circuit Mechanisms of Sensorimotor Learning

Hiroshi Makino, Eun Jung Hwang, Nathan G. Hedrick, Takaki Komiyama
2016 Neuron  
Here we review the current state of our understanding of the modifications in the sensorimotor pathway related to sensorimotor learning.  ...  In this section, we review recent attempts to understand dynamic changes in sensory representations during perceptual learning, and discuss how these changes are implemented through alterations in operation  ...  For instance, neurons in monkey V1 exhibit stronger top-down mediated contextual modulations after training with a three-line bisection task, where the subjectswere asked to report which of the two reference  ... 
doi:10.1016/j.neuron.2016.10.029 pmid:27883902 pmcid:PMC5131723 fatcat:arc2dhec5vb5bbmuryz3jxjd7u

Learning to see again: biological constraints on cortical plasticity and the implications for sight restoration technologies

Michael Beyeler, Ariel Rokem, Geoffrey M Boynton, Ione Fine
2017 Journal of Neural Engineering  
We close by discussing what is known about brain plasticity in sight restoration patients and discuss biological mechanisms that might eventually be harnessed to improve visual learning in these patients  ...  Consequently, the ability of patients to learn to make use of this abnormal retinal input plays a critical role in whether or not some functional vision is successfully regained.  ...  Acknowledgments Supported by the Washington Research Foundation Funds for Innovation in Neuroengineering and Data-Intensive Discovery (MB), by a grant from the Gordon and Betty Moore Foundation and the  ... 
doi:10.1088/1741-2552/aa795e pmid:28612755 pmcid:PMC5953572 fatcat:cqacmghtjfax5ikyusupks24fu

The 9th Asia-Pacific Conference on Vision (APCV 2013)

2013 PsyCh Journal  
Although most insects lack stereo vision, they use a number of ingenious strategies for perceiving their world in three dimensions and navigating successfully in it.  ...  Bees and birds negotiate narrow gaps safely by balancing the apparent speeds of the images in the two eyes.  ...  Our findings demonstrate that there exist eye specific neural activities in V1 that alternate during BR stimulation, such alternation occur without top-down attentional modulation.  ... 
doi:10.1002/pchj.33 fatcat:pvmwjxgldreyvlx47o3pi5ikdi

Visual consciousness in health and disease

Andrew R Whatham, Patrik Vuilleumier, Theodor Landis, Avinoam B Safran
2003 Neurologic clinics  
awareness and performance with neural activity during visual tasks.  ...  Because of its subjective nature, consciousness has been difficult to investigate scientifically, but clues have been gained through studies involving patients with cortical lesions.  ...  in a bisection task (C).  ... 
doi:10.1016/s0733-8619(02)00122-6 pmid:13677817 fatcat:uya3gcelnrgzzgasprrpu3jdfm
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