RT info:eu-repo/semantics/article
T1 Visual processing speed in hemianopia patients secondary to acquired brain injury: a new assessment methodology
A1 Mena-Garcia, Laura
A1 Maldonado-Lopez, Miguel J.
A1 Fernandez, Itziar
A1 Coco Martín, María Begoña
A1 Finat-Saez, Jaime
A1 Martinez-Jimenez, Jose L.
A1 Pastor Jimeno, José Carlos
A1 Arenillas Lara, Juan Francisco
K1 Visual processing speed, Hemianopia, Visual ability, Homonymous visual field defects, Acquired brain injury, Eye-hand coordination, Saccadic eye movements, Visual assessment, Neurovisual rehabilitation
AB Background: There is a clinical need to identify diagnostic parameters that objectively quantify and monitor theeffective visual ability of patients with homonymous visual field defects (HVFDs). Visual processing speed (VPS) is anobjective measure of visual ability. It is the reaction time (RT) needed to correctly search and/or reach for a visualstimulus. VPS depends on six main brain processing systems: auditory-cognitive, attentional, working memory,visuocognitive, visuomotor, and executive. We designed a new assessment methodology capable of activatingthese six systems and measuring RTs to determine the VPS of patients with HVFDs.Methods: New software was designed for assessing subject visual stimulus search and reach times (S-RT and R-RTrespectively), measured in seconds. Thirty-two different everyday visual stimuli were divided in four complexitygroups that were presented along 8 radial visual field positions at three different eccentricities (10o, 20o, and 30o).Thus, for each HVFD and control subject, 96 S- and R-RT measures related to VPS were registered. Three additionalvariables were measured to gather objective data on the validity of the test: eye-hand coordination mistakes(ehcM), eye-hand coordination accuracy (ehcA), and degrees of head movement (dHM, measured by a head-trackersystem). HVFD patients and healthy controls (30 each) matched by age and gender were included. Each subjectwas assessed in a single visit. VPS measurements for HFVD patients and control subjects were compared for thecomplete test, for each stimulus complexity group, and for each eccentricity.Results: VPS was significantly slower (p < 0.0001) in the HVFD group for the complete test, each stimuluscomplexity group, and each eccentricity. For the complete test, the VPS of the HVFD patients was 73.0% slowerthan controls. They also had 335.6% more ehcMs, 41.3% worse ehcA, and 189.0% more dHMs than the controls.Conclusions: Measurement of VPS by this new assessment methodology could be an effective tool for objectivelyquantifying the visual ability of HVFD patients. Future research should evaluate the effectiveness of this novelmethod for measuring the impact that any specific neurovisual rehabilitation program has for these patients.
PB BMC
SN 1743-0003
YR 2020
FD 2020
LK https://uvadoc.uva.es/handle/10324/64439
UL https://uvadoc.uva.es/handle/10324/64439
LA eng
NO J Neuroeng Rehabil. 2020 Jan 31;17(1):12
NO Producción Científica
DS UVaDOC
RD 17-jul-2024