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 #72
Mapping peripheral misreaching in a large stroke cohort
Anouk Smits, University Medical Center Utrecht, Utrecht, Netherlands
Selma Lugtmeijer, University of Birmingham, Birmingham, United Kingdom
Mathijs Raemaekers, University Medical Center Utrecht, Utrecht, Netherlands
Suzanne Hartung, University Medical Center Utrecht, Utrecht, Netherlands
Nick Ramsey, University Medical Center Utrecht, Utrecht, Netherlands
Edward de Haan, Donders Institute Radboud University Nijmegen, Nijmegen, Netherlands
Martine van Zandvoort, University Medical Center Utrecht, Utrecht, Netherlands
Category: Visuospatial Functions/Neglect/Agnosia
Keyword 1: ataxia
Keyword 2: neuroimaging: structural connectivity
Keyword 3: stroke
Objective:
Damage to posterior parietal regions of the brain can lead to changes in visually guided actions, such as pointing, reaching, and grasping. Optic ataxia is a specific deficit in reaching to peripheral targets that is not caused by primary motor weakness or sensory loss. Peripheral misreaching is easily missed in standard neuro(psycho)logical assessment and may go unnoticed as a sign of parietal disfunction or disconnection. Most studies investigating optic ataxia involve case reports and small case series. Here, we systematically address peripheral reaching deficits and associated lesion patterns in a large stroke cohort.
Participants and Methods:
A standardized paradigm and scoring method were developed to assess visually guided reaching and grasping. Data from 86 patients who suffered ischemic stroke and 22 age-matched healthy controls were used for analyses. Each patient also underwent an experimental visual battery and short neuropsychological assessment. Case-control comparisons were performed to compare each individual patient’s peripheral reaching ability against the control distribution. Atlas-based lesion-symptom mapping (LSM) analyses and structural disconnection mapping were performed to identify anatomical correlates of periperhal reaching.
Results:
The developed paradigm is sensitive to individual differences in peripheral reaching ability. Case-control comparisons detected significant peripheral reaching deficits in one-third of stroke patients. Results from atlas-based LSM identified a parietal part of the frontoparietal control network, which corresponds to the supramarginal gyrus, related to peripheral reaching ability in the left visual field. No significant associations were found for the right visual field. Predictions from structural disconnection mapping showed associated disconnection patterns.
Conclusions:
Findings suggest that changes in peripheral reaching are common after stroke, though few cases met the full diagnostic criteria for optic ataxia.
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