Assessing the role of Lesion Volume and Cingulate Gyrus Within the Default Mode Network on Executive Function in Moderate-Severe Traumatic Brain Injury Patients

Open Access
Author:
Patel, Riddhz
Area of Honors:
Psychology
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Frank Gerard Hillary, Thesis Supervisor
  • Frank Gerard Hillary, Honors Advisor
  • Jeff M Love, Faculty Reader
Keywords:
  • Traumatic Brain Injury
  • Cingulate Cortex
  • Default Mode Network
Abstract:
Traumatic Brain Injury (TBI) is a major health and socioeconomic issue that affects over 1.5 million people every year resulting in cognitive impairment and reduced quality of life. Cutting-edge neuroimaging technology such as 3T MRI scanners have facilitated research investigating the role of specific brain structures, lesion volume and different neural network connectivity dynamics which may enhance medical interventions and targeted therapies. The recently evolved structure of the limbic system, cingulate gyrus is involved in the attention, executive processes, word generation, memory and emotion. Due to its functional significance in TBI, examining behavioral effects on task switching and other executive functions post-injury can be give some beneficial insight. Default Mode Network (DMN) is a neural network that includes the posterior cingulate cortex and maintains ongoing resting brain activity. The current study examines total lesion volume, parcellated cingulate gyrus volumes, interconnectivity among the cingulate cortex within the DMN and correlates them with neuropsychology test scores to examine their role in cognitive deficits post injury. Results indicate a statistically significant decrease in the posterior cingulate cortex volume and lower neuropsychological tests scores in TBI participants compared to their healthy controls. Higher total lesion volumes in TBI modestly correlate with poorer neuropsychological performance. Lastly, greater interconnectivity among the CC-DMN was associated with better performance on Digit Span and Trails Making tests among the TBI sample. Future studies should include a larger sample to provide more statistical power between the volumetric, connectivity and behavioral findings.