Default Mode Network Deactivation During Encoding and Retrieval Predicts Performance in Traumatic Brain Injury
Open Access
Author:
Schanz, Olivia Alexandra
Area of Honors:
Psychology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Dr. Frank Gerard Hillary, Thesis Supervisor William Ray, Thesis Honors Advisor
Keywords:
default mode network traumatic brain injury working memory
Abstract:
Traumatic brain injury (TBI) results in 1.7 million cognitive disabilities in the United States each year. Persons with TBI often sustain injury to the prefrontal and frontal cortices. Damage to these areas is assessed through tasks that require working memory (WM). Alterations in neuronal activation during the execution of a task, has lead to the current examination of TBI brain networks during resting state. The default mode network (DMN) is a prominent resting state
network, which engages during stimulus independent mind wandering. DMN is comprised of the posterior cingulated cortex (PCC), and precuneus. Using BOLD fMRI, DMN activity during the encoding, maintenance and retrieval periods of a spatial WM task was observed in 12
participants with moderate-severe TBI. For each participant % signal change across DMN
regions of interest (ROI) were extracted and compared across the three task phases. Encoding
and retrieval showed less deactivation than maintenance. Additionally, less deactivation of the dorsal posterior cingulate cortex (dPCC) and precuneus (pC) were negatively correlated with
performance during encoding and retrieval.
