Building new memories using the past: Interplay between semantic and episodic memory in brains and machines
File(s)
Author(s)
Albesa-González, Albert
Type
Thesis
Abstract
This thesis explores how memories are built through the interaction between episodic
and semantic systems in the brain and in computational models. Episodic memory cap-
tures individual experiences, while semantic memory extracts structure and meaning
across them. Together, they allow both flexible adaptation and long-term stability, a
balance central to cognition. In Chapter 1, our Filopodium–Spine STDP model shows
how distinct synaptic structures support rapid learning and stable retention through
complementary competitive dynamics. In Chapter 2, we propose Homeostatic Binary
Networks, which demonstrate how semantics across concepts and selective represen-
tations can be extracted from highly overlapping representations. In Chapter 3, a
systems-level model reveals how semantic feedback enhances episodic recall, replay,
and compositional consolidation, suggesting a bidirectional dialogue between cortical
and subcortical networks. Across scales, these studies propose that memory formation
relies on cooperation between transient and stable mechanisms, offering insight into
how the brain and artificial systems build new knowledge from the past.
and semantic systems in the brain and in computational models. Episodic memory cap-
tures individual experiences, while semantic memory extracts structure and meaning
across them. Together, they allow both flexible adaptation and long-term stability, a
balance central to cognition. In Chapter 1, our Filopodium–Spine STDP model shows
how distinct synaptic structures support rapid learning and stable retention through
complementary competitive dynamics. In Chapter 2, we propose Homeostatic Binary
Networks, which demonstrate how semantics across concepts and selective represen-
tations can be extracted from highly overlapping representations. In Chapter 3, a
systems-level model reveals how semantic feedback enhances episodic recall, replay,
and compositional consolidation, suggesting a bidirectional dialogue between cortical
and subcortical networks. Across scales, these studies propose that memory formation
relies on cooperation between transient and stable mechanisms, offering insight into
how the brain and artificial systems build new knowledge from the past.
Version
Open Access
Date Issued
2025-10-06
Date Awarded
01/12/2025
License URL
Advisor
Clopath, Claudia
Publisher Department
Department of Bioengineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)