Antonia F Ten Brink1,2, Joris Elshout2, Tanja C W Nijboer2,3, Stefan Van der Stigchel2. 1. Department of Psychology, University of Bath , Bath, UK. 2. Department of Experimental Psychology, Helmholtz Institute, Utrecht University , Utrecht, The Netherlands. 3. Centre of Excellence for Rehabilitation Medicine Utrecht, UMC Utrecht Brain Centre, University Medical Centre Utrecht, and De Hoogstraat Rehabilitation , Utrecht, The Netherlands.
Abstract
INTRODUCTION: Impairments in visual search are a common symptom in visuospatial neglect (VSN). The severity of the lateralized attention bias in visual search tasks can vary depending on the number of distractors: the more distractors, the more targets are missed. However, little is known about how the number of targets affect search performance in VSN. The aim of the current study was to examine the effect of the number of targets on hit rate in VSN. METHODS: We included 23 stroke patients with right-brain damage and VSN, 55 with right-brain damage without VSN, and 49 with left-brain damage without VSN, all admitted for inpatient rehabilitation. In a visual search task, patients had to find and tap targets, presented along with non-targets. The location and number of targets varied from trial to trial, allowing the evaluation of the effects of number and location of targets on hit rate. RESULTS: VSN patients detected a lower percentage of targets when more targets were present. For patients with right-brain damage without VSN, adding targets only reduced the hit rate of the most contralesional target. No effect of number of targets on hit rate was seen in patients with left-brain damage. Additionally, VSN patients found less contralesional targets than ipsilesional targets, made more delayed revisits, and had an initial rightward bias when compared to the other groups. There were no differences in search time, search consistency, or immediate revisits between groups. There was a moderate positive relation between the hit rate asymmetry score in our search task and conventional paper-and-pencil VSN tasks, and neglect behavior in daily life. CONCLUSIONS: In VSN patients, a higher number of targets reduces the hit rate. The reduced hit rate in visual search evoked by additional targets should be taken into account when assessing visual search in VSN.
INTRODUCTION: Impairments in visual search are a common symptom in visuospatial neglect (VSN). The severity of the lateralized attention bias in visual search tasks can vary depending on the number of distractors: the more distractors, the more targets are missed. However, little is known about how the number of targets affect search performance in VSN. The aim of the current study was to examine the effect of the number of targets on hit rate in VSN. METHODS: We included 23 strokepatients with right-brain damage and VSN, 55 with right-brain damage without VSN, and 49 with left-brain damage without VSN, all admitted for inpatient rehabilitation. In a visual search task, patients had to find and tap targets, presented along with non-targets. The location and number of targets varied from trial to trial, allowing the evaluation of the effects of number and location of targets on hit rate. RESULTS: VSN patients detected a lower percentage of targets when more targets were present. For patients with right-brain damage without VSN, adding targets only reduced the hit rate of the most contralesional target. No effect of number of targets on hit rate was seen in patients with left-brain damage. Additionally, VSN patients found less contralesional targets than ipsilesional targets, made more delayed revisits, and had an initial rightward bias when compared to the other groups. There were no differences in search time, search consistency, or immediate revisits between groups. There was a moderate positive relation between the hit rate asymmetry score in our search task and conventional paper-and-pencil VSN tasks, and neglect behavior in daily life. CONCLUSIONS: In VSN patients, a higher number of targets reduces the hit rate. The reduced hit rate in visual search evoked by additional targets should be taken into account when assessing visual search in VSN.
Authors: Sanna Villarreal; Matti Linnavuo; Raimo Sepponen; Outi Vuori; Mario Bonato; Hanna Jokinen; Marja Hietanen Journal: Front Psychol Date: 2022-01-07