Evidence of Impaired Remote Experience-near Semantic Memory in Medial Temporal Lobe Amnesia

Matthew D. Grilli, Sameer Sabharwal-Siddiqi, Sean C. Thayer, Steven Z. Rapcsak, Arne D. Ekstrom

Research output: Contribution to journalArticlepeer-review

Abstract

Neuropsychological research suggests that “experience-near” semantic memory, meaning knowledge attached to a spatiotemporal or event context, is commonly impaired in individuals who have medial temporal lobe amnesia. It is not known if this impairment extends to remotel y acquired experience-near knowledge, which is a question relevant to understanding hippocampal/medial temporal lobe functioning. In the present study, we administered a novel semantic memory task designed to target knowledge associated with remote, “dormant” concepts, in addition to knowledge associated with active concepts, to four individuals with medial temporal lobe amnesia and eight matched controls. We found that the individuals with medial temporal lobe amnesia generated significantly fewer experience-near semantic memories for both remote concepts and active concepts. In comparison, the generation of abstract or “experience-far” knowledge was largely spared in the individuals with medial temporal lobe amnesia, regardless of whether the targets for retrieval were remote or active concepts. We interpret these findings as evidence that the medial temporal lobes may have a sustained role in the retrieval of semantic memories associated with spatiotemporal and event contexts, whi ch are cogni t i ve f eat ures of t en ascribed to episodic memory. These results align with recent theoretical models proposing that the hippocampus/medial temporal lobes support cognitive processes that are involved in, but not exclusive to, episodic memory.

Original languageEnglish (US)
Pages (from-to)2002-2013
Number of pages12
JournalJournal of cognitive neuroscience
Volume35
Issue number12
DOIs
StatePublished - Dec 2023

ASJC Scopus subject areas

  • Cognitive Neuroscience

Fingerprint

Dive into the research topics of 'Evidence of Impaired Remote Experience-near Semantic Memory in Medial Temporal Lobe Amnesia'. Together they form a unique fingerprint.

Cite this