Visual Processing in Cortical Architecture from Neuroscience to Neuromorphic Computing

Primate cortices are organized into different layers which constitute a compartmental structure on a functional level. We show how composite structural elements form building blocks to define canonical elements for columnar computation in cortex. As a further abstraction, we define a dynamical three-stage model of a cortical column for processing that allows to investigate the dynamic response properties of cortical algorithms, e.g., feedforward signal integration as feature detection filters, lateral feature grouping, and the integration of modulatory (feedback) signals. Using such multi-stage cortical model, we investigate the detection and integration of spatio-temporal motion measured by event-based (frame-less) cameras. We demonstrate how the canonical neural circuit can improve such representations using normalization and feedback and develop key computational elements to map such a model onto neuromorphic hardware (IBM’s TrueNorth chip). This makes a step towards implementing real-time and energy-efficient neuromorphic optical flow detectors based on realistic principles of computation in cortical columns.