Bottom-up Processing

Processing that starts from the sensory input itself — the raw data hitting your eyes, ears, etc. — and builds up from there.

Three classic models of how the brain does this in vision:

• Template matching — match the input to a stored pattern
• Feature analysis — identify the component features of a stimulus
• Prototype model — compare the input to an idealized best-fit representation

Contrasts with Top-down Processing, which starts from expectations and context. Most perception is actually a mix of both.