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Competition improves robustness against loss of information.

Kermani Kolankeh A, Teichmann M, Hamker FH - Front Comput Neurosci (2015)

Bottom Line: Therefore, we compared four methods employing different competition mechanisms, namely, independent component analysis, non-negative matrix factorization with sparseness constraint, predictive coding/biased competition, and a Hebbian neural network with lateral inhibitory connections.Also the kind of the competition mechanisms plays an important role in robustness.Global feedback inhibition as employed in predictive coding/biased competition has an advantage compared to local lateral inhibition learned by an anti-Hebb rule.

View Article: PubMed Central - PubMed

Affiliation: Department of Computer Science, Chemnitz University of Technology Chemnitz, Germany.

ABSTRACT
A substantial number of works have aimed at modeling the receptive field properties of the primary visual cortex (V1). Their evaluation criterion is usually the similarity of the model response properties to the recorded responses from biological organisms. However, as several algorithms were able to demonstrate some degree of similarity to biological data based on the existing criteria, we focus on the robustness against loss of information in the form of occlusions as an additional constraint for better understanding the algorithmic level of early vision in the brain. We try to investigate the influence of competition mechanisms on the robustness. Therefore, we compared four methods employing different competition mechanisms, namely, independent component analysis, non-negative matrix factorization with sparseness constraint, predictive coding/biased competition, and a Hebbian neural network with lateral inhibitory connections. Each of those methods is known to be capable of developing receptive fields comparable to those of V1 simple-cells. Since measuring the robustness of methods having simple-cell like receptive fields against occlusion is difficult, we measure the robustness using the classification accuracy on the MNIST hand written digit dataset. For this we trained all methods on the training set of the MNIST hand written digits dataset and tested them on a MNIST test set with different levels of occlusions. We observe that methods which employ competitive mechanisms have higher robustness against loss of information. Also the kind of the competition mechanisms plays an important role in robustness. Global feedback inhibition as employed in predictive coding/biased competition has an advantage compared to local lateral inhibition learned by an anti-Hebb rule.

No MeSH data available.


Related in: MedlinePlus

An example of the input digits under 0-95% occlusions.
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Figure 1: An example of the input digits under 0-95% occlusions.

Mentions: We used a partially occluded test set to study the effect of loss of information on classification: the original non-occluded of MNIST and different occluded versions of it. A test set is formed by applying a particular occlusion level on all images in the original MNIST test set. That is, in each version, the level of occlusion was the same for all digits, although the position of the occluded pixels was generated randomly for each digit. The occluded test sets had an amount of 5–60%, in steps of 5%, occluded pixels. Only digit pixel and no background pixels were occluded. Occlusions were produced by randomly setting non-zero pixel values to zero before whitening an image (Figure 1). Since we are testing on all test sets we will further use the term “test set” to denote all of these test images. No occlusion was applied to the train set.


Competition improves robustness against loss of information.

Kermani Kolankeh A, Teichmann M, Hamker FH - Front Comput Neurosci (2015)

An example of the input digits under 0-95% occlusions.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4373393&req=5

Figure 1: An example of the input digits under 0-95% occlusions.
Mentions: We used a partially occluded test set to study the effect of loss of information on classification: the original non-occluded of MNIST and different occluded versions of it. A test set is formed by applying a particular occlusion level on all images in the original MNIST test set. That is, in each version, the level of occlusion was the same for all digits, although the position of the occluded pixels was generated randomly for each digit. The occluded test sets had an amount of 5–60%, in steps of 5%, occluded pixels. Only digit pixel and no background pixels were occluded. Occlusions were produced by randomly setting non-zero pixel values to zero before whitening an image (Figure 1). Since we are testing on all test sets we will further use the term “test set” to denote all of these test images. No occlusion was applied to the train set.

Bottom Line: Therefore, we compared four methods employing different competition mechanisms, namely, independent component analysis, non-negative matrix factorization with sparseness constraint, predictive coding/biased competition, and a Hebbian neural network with lateral inhibitory connections.Also the kind of the competition mechanisms plays an important role in robustness.Global feedback inhibition as employed in predictive coding/biased competition has an advantage compared to local lateral inhibition learned by an anti-Hebb rule.

View Article: PubMed Central - PubMed

Affiliation: Department of Computer Science, Chemnitz University of Technology Chemnitz, Germany.

ABSTRACT
A substantial number of works have aimed at modeling the receptive field properties of the primary visual cortex (V1). Their evaluation criterion is usually the similarity of the model response properties to the recorded responses from biological organisms. However, as several algorithms were able to demonstrate some degree of similarity to biological data based on the existing criteria, we focus on the robustness against loss of information in the form of occlusions as an additional constraint for better understanding the algorithmic level of early vision in the brain. We try to investigate the influence of competition mechanisms on the robustness. Therefore, we compared four methods employing different competition mechanisms, namely, independent component analysis, non-negative matrix factorization with sparseness constraint, predictive coding/biased competition, and a Hebbian neural network with lateral inhibitory connections. Each of those methods is known to be capable of developing receptive fields comparable to those of V1 simple-cells. Since measuring the robustness of methods having simple-cell like receptive fields against occlusion is difficult, we measure the robustness using the classification accuracy on the MNIST hand written digit dataset. For this we trained all methods on the training set of the MNIST hand written digits dataset and tested them on a MNIST test set with different levels of occlusions. We observe that methods which employ competitive mechanisms have higher robustness against loss of information. Also the kind of the competition mechanisms plays an important role in robustness. Global feedback inhibition as employed in predictive coding/biased competition has an advantage compared to local lateral inhibition learned by an anti-Hebb rule.

No MeSH data available.


Related in: MedlinePlus