Examination and Disturbance of Long-Term Memory (MSE)

1. Overview & Concept

Memory (Gajdos / TOK) is the function by which information stored in the brain is later recalled to consciousness. It proceeds in three steps:

1. Imprinting (encoding/registration)
2. Storing (consolidation/retention)
3. Recalling (retrieval)

Assessed along three characteristics: capacity, durability, accuracy.

Levels of memory (UD/TOK framing):

Long-term memory (LTM) = relatively permanent store with effectively unlimited capacity, holding "general knowledge" and the "curriculum the patient learnt at school" (Gajdos). This topic concerns recent vs remote LTM and its disturbances.

Subdivisions of long-term memory

A. Declarative (explicit) — consciously recalled facts and events; depends on the medial temporal lobe / hippocampus (and, for retrieval of remote memory, diffuse neocortex):

• Episodic — personally experienced events tied to time/place (your wedding, last admission). Autobiographical.
• Semantic — context-free general knowledge (capital cities, who is the Hungarian Prime Minister, days in a year). Survives longer than episodic memory in many disorders.

B. Non-declarative (implicit / procedural) — skills, habits, conditioned and motor learning; unconscious, performed automatically (cycling, tying shoelaces, playing an instrument). Depends on basal ganglia + cerebellum, NOT the hippocampus — therefore typically spared in amnestic syndromes and early dementia (a densely amnestic patient can still learn a motor skill they cannot remember practising).

Recent vs remote long-term memory

• Recent LTM — newly consolidated material (months); the first to fail in most organic memory disorders (hippocampal-dependent).
• Remote LTM — old, over-learned, widely-stored material; relatively resistant, lost only late.

---