![]() ![]() Reaction time (RT) is a particularly useful measure as it can gauge how quickly visual information can be processed to initiate a motor action. 18‐21Ĭritically, these tests have no time limits and are static examinations and thus cannot quantify potentially important impairments in responding to environmental cues. 13‐17 The amount of different tests developed to assess neglect may be attributed to the many proposed subtypes of the disorder. Common assessments include cancellation tests, 5‐8 line bisection tests 4, 9 and figure drawing/copying, 10‐12 which have been shown to be both valid and reliable measures. The focus of these tests is to assess whether individuals with stroke exhibit asymmetry in visual processing by scanning various stimuli on a sheet of paper. 4 There have been many tests developed to quantify visuospatial neglect with the majority based on scores determined by pen and paper examinations. 1‐3 It is commonly characterized by an inability to attend to visual stimuli in the contralesional workspace with a higher prevalence and severity for individuals with right hemisphere damage (RHD) than left hemisphere damage (LHD). Visuospatial neglect is a common disorder seen after stroke although its incidence across studies varies widely from as little as 8% to as high as 80%. Visuospatial neglect, reaction time, Behavioral Inattention Test, reaching, imaging Introduction This study highlights the prevalence and diversity of visuospatial impairments that can occur following stroke. ![]() MRI and CT scans identified distinct white matter and cortical regions of damage for individuals with directional (insula, inferior frontal–occipital fasciculus and inferior longitudinal fasciculus) and general (superior and middle temporal gyri) visuospatial impairment. Behavioral Inattention Test scores significantly correlated ( r = −0.49, P < 0.005) with reaction time impairments but a large portion of individuals not identified as having visuospatial neglect on the Behavioral Inattention Test still displayed reaction time impairments (35%). Impairment in all spatial directions was more prevalent in right than left hemisphere lesions (32% and 12%, respectively). Directional impairments commonly rotated clockwise when reaching with the left versus the right arms. Reaction time impairments were observed in individuals with right or left hemisphere lesions (48% and 30%, respectively). We found that the range of visuospatial impairment can vary dramatically across individuals with some individuals displaying reaction time impairments restricted to a relatively small portion of the workspace, whereas others displayed reaction time impairments in all spatial directions. Participants used both their contralesional and ipsilesional arms to perform a centre-out visually guided reaching task in the horizontal plane. In this study, we quantify the ability of a large cohort of 204 healthy control participants (females = 102) and 265 individuals with stroke (right hemisphere damage = 162, left hemisphere damage = 103 mean age 62) to generate goal-directed reaches. However, little is known of the visuospatial impairment in other spatial directions and, further, the influence of the arm being assessed. Numerous studies of impairment after visuospatial neglect demonstrate delayed reaction times when reaching to the left. Clinical diagnosis is largely based on performance on pen and paper examinations that are unable to accurately measure the speed of processing environmental stimuli-important for interacting in our dynamic world. Visuospatial neglect is a disorder characterized by an impairment of attention, most commonly to the left side of space in individuals with stroke or injury to the right hemisphere. ![]()
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