Semantic Memory

Hierarchical Semantic Network

A model where concepts are organized into a hierarchy (animal → bird → canary), with features attached at the most general level they apply.

Why hierarchical?

Cognitive economy: store a shared feature once at the highest level it’s true, instead of duplicating it at every descendant.

  • Canary inherits “has feathers” from bird
  • Bird inherits “is alive” from animal

Predicts reaction-time patterns: verifying “a canary is alive” is slower than “a canary is yellow” because more levels are traversed. Works alongside Spreading Activation as a mechanism for retrieval.