Visuomotor Strategies and the Role of Spatial Memory for Regressive Saccades in Reading

The current study examined the control of long-range regressive eye movements during sentence reading. Skilled readers were asked to read single-line sentences for comprehension. As a secondary task, they identified a probe word presented to the right of each sentence, and then went back to check the corresponding target word for spelling errors that had been added after reading. The regression target was located either close to or far from the probe. Eye movement measures included the size of initial regressions, regression error, number of regressions and time to reach the target. Assessments of spatial memory capacity and reading skill served to determine the use of spatial and linguistic knowledge. Responses were classified into five different visuomotor strategies: single shot regressions, goal directed regressions (with corrections), centered searches, forward searches, and backward searches. Consistent with prior work, initial regressions were larger for far than for near targets, and the finding of far targets required more eye movements and more search time. Spatial memory and reading skill made distinct contributions to regression targeting. Memory skills strongly determined primary regressions especially to near targets, whereas reading ability influenced the time needed to attain targets with subsequent saccades.