Poster A38, Saturday, March 25, 5:00 – 7:00 pm, Pacific Concourse
Ventromedial prefrontal cortex plays a critical role in schematic support of short-term memory
Liz Race1,2, Hope Tobin1,2, Mieke Verfaellie2,3; 1Tufts University, 2VA Boston Healthcare System, 3Boston University School of Medicine
The ability to integrate novel information with stored knowledge (schemas) can facilitate both short-term memory (STM) and long-term memory (LTM). Evidence suggests that the ability to leverage stored knowledge in support of LTM involves a hippocampal-ventromedial prefrontal (vmPFC) circuit (Schlichting & Preston, 2015), but whether these structures are also involved in the schematic facilitation of STM is unknown. Recently, we demonstrated that the hippocampus is not necessary for the schematic facilitation of STM (Race et al., 2015). The current study was designed to investigate whether vmPFC supports STM-LTM integration, and if so, to elucidate its role. One possibility is that vmPFC supports schema reinstatement or representation (Ghosh et al., 2014). Alternatively, vmPFC may support the integration of to-be-remembered information with activated schema representations (Spalding et al., 2015). To investigate these possibilities, patients with lesions to vmPFC (n=8) and healthy controls (n=19) performed two tasks that examined schema representation and memory integration, respectively. In the schema representation task, participants entered digits as quickly as possible into a keypad that had either a familiar visuospatial layout (typical keypad) or unfamiliar visuospatial layout (atypical keypad). In the STM-LTM integration task, participants performed immediate serial recall of digits that were presented in either the familiar or unfamiliar keypad layouts. Patients showed a typical keypad advantage of the same magnitude as controls in the schema representation task, but not in STM-LTM integration task. These results reveal that vmPFC plays a critical role in STM-LTM integration, but not in schema representation.
Topic Area: EXECUTIVE PROCESSES: Working memory