Hybrid Predictive Coding: Inferring, Fast and Slow

Understand

Predictive coding is an influential model of cortical neural activity.

• It proposes that perceptual beliefs are furnished by sequentially minimising "prediction errors" - the differences between predicted and observed data.
• Implicit in this proposal is the idea that perception requires multiple cycles of neural activity.
• This is at odds with evidence that several aspects of visual perception - including complex forms of object recognition - arise from an initial "feedforward sweep" that occurs on fast timescales which preclude substantial recurrent activity.