Bilateral damage to the hippocampus (as occurred in patient H.M.) results in which specific and lasting memory deficit?

• A Loss of all previously stored long-term explicit memories (retrograde amnesia for remote events)
• B Loss of procedural (implicit) memory such as motor skills
• C Profound loss of language function (aphasia)
• D Inability to form new long-term declarative (explicit) memories — anterograde amnesia — with preserved working and procedural memory ✓

Explanation

Bilateral hippocampal damage causes a severe anterograde amnesia — the inability to consolidate new declarative (explicit) memories, both episodic and semantic. Working memory and procedural (implicit) memory such as motor skill learning (mediated by the basal ganglia and cerebellum) are preserved. Remote long-term memories stored before the lesion are largely intact. Language is not dependent on hippocampal integrity.

Reference: Guyton & Hall, Textbook of Medical Physiology, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.