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invariant object recognition - Visnet

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Computational models of invariant object recognitionSupervisor: Dr. Reza EbrahimpourStudent: Alireza Akhavan Pour

HMAX VisNet

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VIEW ON THE VISUAL PATHWAY

Visual Areas of the Human Cerebral Cortex5/31

On center

No lightLight onNo light

No lightLight onNo light

Off center

Neurons and areas in visual system 14/40VIEW ON THE VISUAL PATHWAY

BEHAVIOR OF AN GANGLION CELL 6/31

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No lightwrong position-wrong orientationwright position-wrong orientationwrong position-wright orientationWright positionWright orientation

VIEW ON THE VISUAL PATHWAY, SIMPLE CORTICAL CELLS7/31

Behavior of a complex cell 8/31

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9 HMAX VisNet

Hmax Hubel Wiesel Hubel Wiesel :

( receptive field) : (feed-forward)

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4 11/31V1-V2

V1-V2

V2-V4

V4/PIT

ITS1

C1

S2

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12 HMAX VisNet

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Continuous transformation (CT) learning

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:VisNet15/31

VisNet 16/31Edmund T. Rolls

4 (local graded inhibition) (topologicall) (modified Hebbian learning rule )V2-> V4->posterior inferior temporal -> anterior inferior temporal

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67%

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Architecture17/31

1 V1

input18/31

Input to layer 1

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I .

4- .

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4 3 2 191889899.2267540190

contrast enhancement (contrast enhancement) 0 1

:r ( ) : y : ( !) : activation

sparseness21/31

(trace learning rule) :

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xj j- y t y t wj j- trace value ( )

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Neural-like models via performance optimizationD. . L. K. Yamins, H. Hong, C. F. Cadieu, E. A. Solomon, D. Seibert and J. J. DiCarlo, "Performance-optimized hierarchical models predict neural responses in higher visual cortex," Proceedings of the National Academy of Sciences, p. 201403112, 2014. 25/31

VisNet Hmax

VisnetHmaxtesttesttraintrain26/31

27 HMAX VisNet

invariency (re-train) GPU Spike 28/31

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29References

E. Rolls, " Invariant visual object and face recognition: neural and computational bases, and a model," In Computational Neuroscience, vol. 51, pp. 167194, 2012.

T. Rolls, E.T., and Stringer, "Continuous transformation learning of translation invariant representations," Exp.BainRes, pp. 255270, 2010.

D. L. K. Yamins, H. Hong, C. F. Cadieu, E. A. Solomon, D. Seibert and J. J. DiCarlo, "Performance-optimized hierarchical models predict neural responses in higher visual cortex," Proceedings of the National Academy of Sciences, p. 201403112, 2014.

M. Riesenhuber and T. Poggio, "Hierarchical Models of Object Recognition in Cortex," Nature Neuroscience, vol. 2, no. 11, pp. 1019-1025, 1999.

Stringer, S. M. and E. T. Rolls. 2008. Learning transform invariant object recognition in the visual system withmultiple stimuli present during training, Neural Networks 21:888-903

REFERENCES30/31

[1] E. a. T. Rolls, " Processing speed in the cerebral cortex and the neurophysiology of visual masking. Proc.R.Soc.Lond.BBiol.Sci. 257, 915.," 1994.

[2] S. S. P. a. N. R. Hestrin, "Mechanisms generating the time course of dual component exci tatory synaptic currents recorded in hippocampal slices.," Neuron 5, 1990

[3] P. G. J. a. E. m. G. Montague, "Spatial signalling in the development and function of neural connections," Cereb.Cortex 1, 199220.REFERENCES31/31