Semantic Memory in Traumatic Brain Injury: An Examination of Word Features

Abstract

Semantic memory, or the stored knowledge for words and concepts, is the basis for nearly all human behavior, and is critical for academic, vocational, and interpersonal pursuits. As part of the declarative memory system, semantic memory is reliant on a network of interconnected neural structures throughout cortex to function. The neuropathologies of TBI damage these structures and their connections, predicting some level of semantic memory dysfunction that may be contributing to poor outcomes in TBI. Detecting changes to semantic memory in TBI using standardized assessments designed to capture frank impairment in other disorders has proved difficult, resulting in inconsistent findings and conclusions. Here, we use an experimental paradigm shown sensitive to subtle semantic memory disruption in other populations with acquired brain injury to examine semantic memory in a group of individuals with chronic moderate-severe TBI and demographically matched comparison participants. We employ complementary behavioral and computational analyses to demonstrate subtle but reliable semantic memory disruptions in TBI, laying the groundwork for further programmatic investigation of semantic memory in this population.