INS NYC 2024 Program

Poster	Poster Session 03 Program Schedule 02/15/2024 09:30 am - 10:40 am Room: Majestic Complex (Posters 61-120) Poster Session 03: Neurotrauma \| Neurovascular Final Abstract #63 A Neural Examination of Spatial Neglect in Individuals with Traumatic Brain Injury Megan Rusco, Kessler Foundation, West Orange, United States Olga Boukrina, Kessler Foundation, West Orange, United States Suchir Pongurlekar, Kessler Foundation, West Orange, United States Emma Kaplan, Kessler Foundation, West Orange, United States Peii Chen, Kessler Foundation, West Orange, United States Category: Visuospatial Functions/Neglect/Agnosia Keyword 1: traumatic brain injury Keyword 2: visuospatial neglect Keyword 3: neuroimaging: structural Objective: Spatial neglect (SN) is a common neurological disorder among brain injury survivors. SN occurs in more than 50% of stroke survivors at the acute stage, and 30% of affected individuals continue to have chronic SN. Behaviorally, SN is characterized by decreased attention, action, and orientation toward the neglected part of space (typically the left). While much has been learned from stroke survivors, little is known about SN among individuals who sustained traumatic brain injury (TBI), and who may experience SN at a rate of 30-45%. The present study aims to explore the neural basis of SN among individuals with moderate-to-severe TBI. Participants and Methods: This study included 15 participants who had sustained moderate-to-severe TBI more than 12 months prior (2 women; M age = 45.7 years; average time post-injury = 105.9 months). SN was determined through paper-based neuropsychological tests including line bisection and two target cancellation tests, the 3s Spreadsheet Test and the Apples Test. We used performance on the cancellation tests to compute egocentric and allocentric asymmetry scores and recorded the starting column (1-10 starting with the left column). Average deviation from the center (in mm) was recorded for line bisection. All negative scores (e.g., asymmetry to the left vs. right) were converted to absolute values for the analyses (high scores indicating worse SN). Anatomical brain images were collected using a Siemens MAGNETOM Skyra 3T MRI scanner. T1- and T2 FLAIR-weighted images were used to map lesions using a combination of automatic and manual voxel selection. To study the relationship between lesion location and SN severity, we conducted a series of voxelwise lesion-symptom mapping (VLSM) analyses using VLSM2 software version 2.6 (Bates et al., 2003). We controlled for lesion volume as a proxy for injury severity. Results: Typical behavior among users of left-to-right writing systems is to begin target cancellation at the left most column. Therefore, when participants began target cancellation on the right, we considered this an indication of spatial neglect. We found the starting column of the Apples Test, i.e., starting closer to the right side of the page, correlated to lesions in the right anterior superior frontal gyrus. Lesions to the left inferior fronto-occipital fasciculus and left anterior thalamic radiation were associated with higher line bisection deviations (both results: p<0.05, one-tailed, uncorrected). Conclusions: Our findings are consistent with results reported in chronic stroke, suggesting that the inferior fronto-occipital fasciculus and reduced integrity of white matter tracts in both hemispheres play a critical role in SN persistence. Although frontal cortex dysfunction has been implicated in post-stroke SN, superior frontal gyrus lesions have not been previously reported in stroke survivors, which could be related to fewer strokes affecting this area. While our findings remain to be replicated in a larger sample, we conclude that individuals with TBI should be screened and treated for SN, as their diffuse white matter damage may precipitate the clinical impact of SN.

Poster

02/15/2024
09:30 am - 10:40 am
Room: Majestic Complex (Posters 61-120)

Poster Session 03: Neurotrauma | Neurovascular

Final Abstract #63

A Neural Examination of Spatial Neglect in Individuals with Traumatic Brain Injury

Megan Rusco, Kessler Foundation, West Orange, United States
Olga Boukrina, Kessler Foundation, West Orange, United States
Suchir Pongurlekar, Kessler Foundation, West Orange, United States
Emma Kaplan, Kessler Foundation, West Orange, United States
Peii Chen, Kessler Foundation, West Orange, United States

Category: Visuospatial Functions/Neglect/Agnosia

Keyword 1: traumatic brain injury
Keyword 2: visuospatial neglect
Keyword 3: neuroimaging: structural

Objective:

Spatial neglect (SN) is a common neurological disorder among brain injury survivors. SN occurs in more than 50% of stroke survivors at the acute stage, and 30% of affected individuals continue to have chronic SN. Behaviorally, SN is characterized by decreased attention, action, and orientation toward the neglected part of space (typically the left). While much has been learned from stroke survivors, little is known about SN among individuals who sustained traumatic brain injury (TBI), and who may experience SN at a rate of 30-45%. The present study aims to explore the neural basis of SN among individuals with moderate-to-severe TBI.

Participants and Methods:

This study included 15 participants who had sustained moderate-to-severe TBI more than 12 months prior (2 women; M age = 45.7 years; average time post-injury = 105.9 months). SN was determined through paper-based neuropsychological tests including line bisection and two target cancellation tests, the 3s Spreadsheet Test and the Apples Test. We used performance on the cancellation tests to compute egocentric and allocentric asymmetry scores and recorded the starting column (1-10 starting with the left column). Average deviation from the center (in mm) was recorded for line bisection. All negative scores (e.g., asymmetry to the left vs. right) were converted to absolute values for the analyses (high scores indicating worse SN). Anatomical brain images were collected using a Siemens MAGNETOM Skyra 3T MRI scanner. T1- and T2 FLAIR-weighted images were used to map lesions using a combination of automatic and manual voxel selection. To study the relationship between lesion location and SN severity, we conducted a series of voxelwise lesion-symptom mapping (VLSM) analyses using VLSM2 software version 2.6 (Bates et al., 2003). We controlled for lesion volume as a proxy for injury severity.

Results:

Typical behavior among users of left-to-right writing systems is to begin target cancellation at the left most column. Therefore, when participants began target cancellation on the right, we considered this an indication of spatial neglect. We found the starting column of the Apples Test, i.e., starting closer to the right side of the page, correlated to lesions in the right anterior superior frontal gyrus. Lesions to the left inferior fronto-occipital fasciculus and left anterior thalamic radiation were associated with higher line bisection deviations (both results: p<0.05, one-tailed, uncorrected).

Conclusions:

Our findings are consistent with results reported in chronic stroke, suggesting that the inferior fronto-occipital fasciculus and reduced integrity of white matter tracts in both hemispheres play a critical role in SN persistence. Although frontal cortex dysfunction has been implicated in post-stroke SN, superior frontal gyrus lesions have not been previously reported in stroke survivors, which could be related to fewer strokes affecting this area. While our findings remain to be replicated in a larger sample, we conclude that individuals with TBI should be screened and treated for SN, as their diffuse white matter damage may precipitate the clinical impact of SN.