[Paper Review] A consequence of failed sequential learning: A computational account of developmental amnesia

Zhang, Qi|arXiv (Cornell University)|Feb 13, 2026

Memory and Neural Mechanisms0 citations

TL;DR

The paper presents a cognitive model showing that impaired sequential/spatial learning in the hippocampus can produce developmental amnesia with severely impaired episodic recall but preserved recognition and semantic learning. It also simulates retrograde amnesia.

ABSTRACT

Developmental amnesia, featured with severely impaired episodic memory and almost normal semantic memory, has been discovered to occur in children with hippocampal atrophy. This unique combination of characteristics seems to challenge the understanding that early loss of episodic memory may impede cognitive development and result in severe mental retardation. Although a few underlying mechanisms have been suggested, no computational model has been reported that is able to mimic the unique combination of characteristics. In this study, a cognitive system is presented, and developmental amnesia is demonstrated computationally in terms of impaired episodic recall, spared recognition and spared semantic learning. Impaired sequential/spatial learning ability of the hippocampus is suggested to be the cause of such amnesia. Simulation shows that impaired sequential leaning may only result in severe impairment of episodic recall, but affect neither recognition ability nor semantic learning. The spared semantic learning is inline with the view that semantic learning is largely associated with the consolidation of episodic memory, a process in which episodic memory may be mostly activated randomly, instead of sequentially. Furthermore, retrograded amnesia is also simulated, and the result and its mechanism are in agreement with most computational models of amnesia reported previously.

Motivation & Objective

• Motivate developmental amnesia as a challenge to existing views of early episodic memory loss and cognitive development.
• Demonstrate a cognitive system that reproduces the triad: impaired episodic recall, preserved recognition, and preserved semantic learning.
• Explore how impaired sequential learning in the hippocampus leads to observed memory profiles.

Proposed method

• Develop a cognitive system that embodies sequential/spatial learning mechanisms.
• Simulate impaired sequential learning and observe effects on episodic recall, recognition, and semantic learning.
• Model consolidation processes to connect episodic activity with semantic learning.
• Simulate retrograde amnesia and compare with established computational accounts.

Experimental results

Research questions

• RQ1 Can impaired sequential learning in a hippocampal-like system account the selective memory profile of developmental amnesia (severely impaired episodic recall with spared recognition and semantic learning)?
• RQ2 What is the role of sequential vs. non-sequential memory processes in driving episodic versus semantic memory outcomes in the model?
• RQ3 Does the model reproduce retrograde amnesia patterns aligned with prior computational accounts?

Key findings

• Impaired sequential learning yields severe episodic recall impairment while recognition and semantic learning remain spared.
• Semantic learning aligns with consolidation of episodic memory, possibly activated randomly rather than sequentially.
• Retrograde amnesia can be simulated and matches expectations from previous computational models of amnesia.