---
title: "Memory Systems: What Amnesia Separates"
description: "Memory is not one store: patients who cannot form new episodes still learn skills, and that dissociation is the main evidence that different structures do different jobs. The hippocampus is needed to "
canonical: https://lightmysky.com/learn/science/memory-systems-what-amnesia-separates-mt_oNFXpEHl8b
source: https://lightmysky.com/learn/science/memory-systems-what-amnesia-separates-mt_oNFXpEHl8b.md
retrieved: 2026-09-12
---

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# Memory Systems: What Amnesia Separates

Memory is not one store: patients who cannot form new episodes still learn skills, and that dissociation is the main evidence that different structures do different jobs. The hippocampus is needed to acquire an episode but not to keep it forever, which is why consolidation is treated as a separate process.

Subject: Science · Area: The Human Body · Ages 21 to 22
Page: https://lightmysky.com/learn/science/memory-systems-what-amnesia-separates-mt_oNFXpEHl8b

## Ready when they can

- Distinguish declarative from non-declarative memory using evidence from a described case
- Explain what systems consolidation claims and what evidence supports it
- Relate a synaptic change to a behavioural memory without claiming they are the same thing

## Lesson: The many stores of memory

Memory is not one store. Declarative memory holds facts and episodes you can say out loud, like what you ate for breakfast. Non-declarative memory holds skills and habits you show by doing, like riding a bike. Saying versus doing is the split.

**Example.** Patients with hippocampus damage cannot form new episodes yet still learn new skills. They improve at a task across days while denying they ever practiced it. That dissociation is the main evidence that different structures do different jobs.

Consolidation is the slow process that settles a new memory into long term storage. The hippocampus is needed to acquire an episode and start that process, but not to keep it forever. Starting a memory and storing it are separate jobs.

**Tip.** A synaptic change can relate to a behavioural memory without being the same thing as the memory. Link brain changes to behaviour carefully: they support the memory, they are not the memory itself. Never collapse the two levels into one.

**Recap.** Different stores do different jobs, the hippocampus starts consolidation, and synapses support memories without being them.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [Synaptic Plasticity and the Molecular Rules of Change](https://lightmysky.com/learn/science/synaptic-plasticity-and-the-molecular-rules-of-change-mt_HldevO4Lzw)
- [Motor Control: From Intention to Muscle](https://lightmysky.com/learn/science/motor-control-from-intention-to-muscle-mt_hrWOuRtPDl)

## Opens up

- [Sleep, Circadian Rhythms and the Clock in the Brain](https://lightmysky.com/learn/science/sleep-circadian-rhythms-and-the-clock-in-the-brain-mt_cXx4SaLJUM)