Five-Tier Memory Cascade

Problem

A flat append-only log collapses signal across timescales: a momentary observation and a stable identity fact look the same and compete for attention. Pure long-term memory, on the other hand, cannot capture momentary salience — a recent flick of attention that needs to live for the next few minutes and then expire. Without an explicit cascade that separates working memory from short-term, episodic, semantic, and long-term tiers, each with its own decay and promotion rules, the agent either drowns in stale recent noise or forgets the very fast signals it needs in order to respond well.

Solution

Five tiers. Sensory: raw input per tick. Working: top-N items in active focus (Global Workspace Theory, ≤7 items). Short-term: recent verbatim (1-7 days). Episodic: compressed summaries (5-10x). Long-term: distilled rules and insights. Compaction promotes upward on a schedule; decay archives downward; rehearsal lifts archived items back when re-attended.

When to use

• A flat append-only log is collapsing signal across timescales (sensory, working, recent, episodic, distilled).
• Promotion and decay between tiers can be implemented on a schedule.
• Working memory needs an explicit cap (e.g. ≤7 items, Global Workspace Theory).