Spatial load factor in prediction of reading performance

Abstract

This study investigated whether there is a relationship between reading age and clinical optometric tests that have varying degrees of spatial loading in their design. Spatial loading in this context is the demand on the visual system to process information about the relative position and orientation of stimuli. A total of 112 children aged 8-11 years were assessed using saccadic eye movement and rapid naming tasks with varying spatial loads. All were subtests of Garzia's Developmental Eye Movement test and Liubinas' SeeRite Reading Diagnostic Programme. Variability in load was achieved by comparing rapid naming of numerals vs the spatially loaded letters p, d, b, q; and by comparing the speed of reading numerals presented in increasingly complex arrays. Reading Age was assessed independently and results were analysed by multiple logistic regression. Spatially loaded naming tasks performed at speed exposed a Spatial Loading Factor which clearly differentiates children at risk with reading.

Eye movement patterns and reading ability in children

“…reported that while the timed DEM metrics were not related to horizontal saccadic gain, accuracy, speed or initiation assessed using standard eye tracking instrumentation, they were significantly correlated with visual processing speeds and reading ability, indicating that the DEM test can identify those at risk of reading delay. This association between reading ability and the DEM test in children has been confirmed in several studies using a range of standardised reading tests 12,14–16 …”

“…Few studies have explored eye movement behaviour in children with a range of reading abilities (rather than those diagnosed as having dyslexia) using eye tracking during saccadic tasks where target spacing is irregular and simulates the variable saccadic demands encountered during reading. Investigating eye movements during these types of saccadic tasks is of interest, given that timed metrics from saccadic tasks with complex spacing (multi‐line arrays with irregular horizontal target spacing) have been found to be more effective in identifying children with poor reading skills compared to single‐line saccadic tasks with regular spacing between targets 12 …”

Relationship between oculomotor scanning determined by the DEM test and a contextual reading test in schoolchildren with reading difficulties

“…3 Horizontal DEM test results obtained in the current study (in poor readers) compared to normative data [4], and in other studies performed on unselected readers [11,12] and a learning-disabled sample (LDS) [4] Age Vertical DEM test results obtained in the current study (in poor readers) compared to normative data [4] and in other studies performed on unselected readers [11,12] and a learning-disabled sample (LDS) [4] Age (years) Ratio DEM (horizontal time/vertical time) 8 1 0 [4], and in other studies performed on unselected readers [11,12] and a learningdisabled sample (LDS) [4] 12]. While the vertical DEM is a task of low spatial demand, the horizontal DEM test is more spatially demanding, and has been used to predict below average readers [10]. According to Garzia et al [4], the vertical response reflects automaticity skills, and horizontal response levels are a measure of automaticity, ocular fixation and saccades skills.…”

“…Its design reflects the combination of saccadic eye movements, spatial load and speed skills [10]. The DEM test assesses the speed and accuracy at which a series of single-digit numbers can be seen, recognized, and verbalized.…”

“…Few authors have compared horizontal scanning using a reading test and a number-naming task. Larter et al [10] found that the horizontal DEM test clearly differentiates children at risk of having problems with reading, and Northway [14] observed that dyslexic children who scored lower in the rate of reading test (RRT) took longer at the horizontal DEM test. However, this relationship has not been examined in poor readers without dyslexia.…”