Eye movement and online bisection task in unilateral patients with neglect: A new look to the ‘gradient effect’

Balconi, Michela; Amenta, Simona; Sozzi, Matteo; Cannatà, Anna Paola; Pisani, Luigi

doi:10.3109/02699052.2012.750739

“…Task: Studies were included where visuospatial bias was assessed using standard versions of either the line bisection task or the landmark task. Non-standard versions, such as gap bisection (e.g., Balconi et al, 2013), sentence bisection (Arduino et al, 2016), and rods that were bisected via tactile exploration (Brooks et al, 2011), were excluded. Only lines presented horizontally were included, and those presented vertically (e.g., Lee et al, 2002) or radially (e.g., Barrett & Craver-Lemley, 2008) were excluded.…”

Section: Study Selectionmentioning

confidence: 99%

A Meta-Analysis of Line Bisection and Landmark Task Performance in Older Adults

Learmonth

¹

,

Παπαδάτου-Παστού

²

2021

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Young adults exhibit a small asymmetry of visuospatial attention that favours the left side of space relative to the right (pseudoneglect). However, it remains unclear whether this leftward bias is maintained, eliminated or shifted rightward in older age. Here we present two meta-analyses that aimed to identify whether adults aged ≥50 years old display a group-level spatial attention bias, as indexed by the line bisection and the landmark tasks. A total of 69 datasets from 65 studies, involving 1654 participants, were analysed. In the meta-analysis of the line bisection task (n = 63), no bias was identified for studies where the mean age was ≥50, but there was a clear leftward bias in a subset where all individual participants were aged ≥50. There was no moderating effect of the participant’s age or sex, line length, line position, nor the presence of left or right cues. There was a small publication bias in favour of reporting rightward biases. Of note, biases were slightly more leftward in studies where participants had been recruited as part of a stand-alone older group, compared to studies where participants were recruited as controls for a clinical study. Similarly, no spatial bias was observed in the meta-analysis of the landmark task, although the number of studies included was small (n = 6). Overall, these results indicate that over 50s maintain a group-level leftward bias on the line bisection task, but more studies are needed to determine whether this bias can be modulated by stimulus- or state-dependent factors.

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“…Secondly, AAP's visual exploration was limited to the gaze orientation and followed as expected a gradient of attention, such as a progressive and gradual increase of visual exploration from the extreme left to the right. In our previous works, 28,31 we observed behavioural and eye-movement variations along a left-to-right horizontal continuum in patients with neglect. We modified the line bisection test in a space bisection task and asked patients to find the exact half-point between two extremities.…”

Section: Discussionmentioning

confidence: 73%

“…Thus, it is globally assumed that prime words could be processed in neglect patients but no evidences are provided on implicit processing in hemianopia. Moreover, studies so far limited the observations to left and right hemispaces without exploring variations on a gradient perception of space (28).…”

Section: Introductionmentioning

confidence: 99%

“…Secondly, we aim to demonstrate if the presence/absence of implicit processing in the case of neglected field could be observed along a spatial continuum (based on a sort of gradient effect), instead of a simple left/right hemispace difference. Indeed, we suppose that neglect can vary and progressively reduces through rightward direction- 28 (from the neglected to the preserved hemispace). For this reason, we may expect different effects of priming along this spatial continuum (from less to more significant effect) whilst no gradient variation should be observed in hemianopic visual field, where the prime effect is supposed to be absent.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Which Differences in Priming Effect Between Neglect and Hemianopia? A Case Description of a Bilateral Brain-Lesioned Patient

Sozzi¹,

Marzoli

²

,

Melzi

³

et al. 2017

Neuro-Ophthalmology

Self Cite

1

0

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It is widely known that visuospatial neglect and hemianopia maybe superimposed. We considered the differences in implicit information processing which is effective in patients with neglect but not with hemianopia. We then hypothesize that a prime-word in the neglected field should determine a semantic activation effect but not in a blind hemifield. Moreover eye movements could provide further details. In this work we considered a patient with a bilateral with the presence of either a left visual neglect and a right homonymous hemianopia. Our results supported implicit information processing in the space affected by neglect but not by hemianopia.

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“…3) Task: Studies were included where visuospatial bias was assessed using standard versions of either the line bisection task or the landmark task. Non-standard versions, such as gap bisection (e.g., Balconi et al 2013), sentence bisection (Arduino et al 2016), and rods that were bisected via tactile exploration (Brooks et al 2011), were excluded. Only lines presented horizontally were included, and those presented vertically (e.g., Lee et al 2002) or radially (e.g., Barrett and Craver-Lemley 2008) were excluded.…”

Section: Study Selectionmentioning

confidence: 99%

A meta-analysis of line bisection and landmark task performance in older adults

Learmonth¹,

Παπαδάτου-Παστού²

2021

Preprint

3

0

View full text Add to dashboard Cite

Young adults exhibit a small asymmetry of visuospatial attention that favours the left side of space relative to the right (pseudoneglect). However, it remains unclear whether this leftward bias is maintained, eliminated or shifted rightward in older age. Here we present two meta-analyses that aimed to identify whether adults aged ≥50 years old display a group-level spatial attention bias, as indexed by the line bisection and the landmark tasks. A total of 69 datasets from 65 studies, involving 1654 participants, were analysed. In the meta-analysis of the line bisection task (n = 63), no bias was identified for studies where the mean age was ≥50, but there was a clear leftward bias in a subset where all individual participants were aged ≥50. There was no moderating effect of the participant’s age or sex, line length, line position, nor the presence of left or right cues. There was a small publication bias in favour of reporting rightward biases. Of note, biases were slightly more leftward in studies where participants had been recruited as part of a stand-alone older group, compared to studies where participants were recruited as controls for a clinical study. Similarly, no spatial bias was observed in the meta-analysis of the landmark task, although the number of studies included was small (n = 6). Overall, these results indicate that over 50s maintain a group-level leftward bias on the line bisection task, but more studies are needed to determine whether this bias can be modulated by stimulus- and/or state-dependent factors.

show abstract

Eye movement and online bisection task in unilateral patients with neglect: A new look to the ‘gradient effect’

Abstract: Although a left-to-right and longer-to-shorter 'continuous-gradient effect' was not supported by the results, an 'extreme left-gradient effect' was suggested and discussed.

Cited by 7 publications

References 28 publications

A Meta-Analysis of Line Bisection and Landmark Task Performance in Older Adults

A Meta-Analysis of Line Bisection and Landmark Task Performance in Older Adults

Which Differences in Priming Effect Between Neglect and Hemianopia? A Case Description of a Bilateral Brain-Lesioned Patient

A meta-analysis of line bisection and landmark task performance in older adults

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