Recurrent models of orientation selectivity enable robust early-vision processing in mixed-signal neuromorphic hardware


Loading...

Date

2023-10-10

Publication Type

Working Paper

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

Mixed signal analog/digital neuromorphic circuits represent an ideal medium for reproducing the dynamics of biological neural systems in real-time with bio-physically realistic dynamics. However, similar to their biological counterparts, these circuits have limited resolution and are affected by a high degree of variability. Considering this, we developed a recurrent spiking neural network that implements a faithful model of the retinocortical visual pathway to reliably produce Gabor-like receptive fields tuned to visual stimuli with specific orientation and spatial frequency properties. Specifically, we developed a neuromorphic visual system comprising a Dynamic Vision Sensor that emulates the transient pathway of real retinas and a mixed-signal Dynamic Neuromorphic Asynchronous Processor with adaptive exponential integrate-and-fire neurons and dynamic synapses and mapped the recurrent network model on it to produces the desired orientation and spatial frequency tuning responses. Compared to alternative feed-forward schemes, the model developed gives rise to robust highly structured Gabor-like receptive fields of any phase symmetry, optimizing the hardware resources available in terms of synaptic connections. We present experimental results using both synthetic and natural images validating the model with its hardware implementations.

Publication status

published

Editor

Book title

Volume

Pages / Article No.

Publisher

Research Square

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Organisational unit

09699 - Indiveri, Giacomo / Indiveri, Giacomo check_circle

Notes

Funding

Related publications and datasets