Flexibility in the perceptual span during reading: Evidence from Mongolian

Area of Science:

• Cognitive Psychology
• Linguistics
• Neuroscience

Background:

• Reading involves processing text within a limited perceptual span around each fixation point.
• This span is typically asymmetric, extending in the direction of reading.
• Previous research shows asymmetry reversal with horizontal reading direction changes, but less is known about orthogonal (vertical vs. horizontal) changes.

Purpose of the Study:

• To investigate the flexibility of the perceptual span across orthogonal changes in reading direction.
• To examine reading behavior in Mongolian, a language with both vertical and horizontal writing systems, to avoid confounds.

Main Methods:

• Utilized a gaze-contingent paradigm to manipulate the visible text region around fixations.
• Presented Mongolian sentences in both vertical and horizontal reading orientations.
• Compared reading rates and perceptual span effects between the two reading directions.

Main Results:

• Perceptual span effects on reading rates were found to be similar regardless of whether text was read horizontally or vertically.
• This indicates that the perceptual span adapts flexibly to orthogonal changes in reading direction.

Conclusions:

• The perceptual span demonstrates flexibility not only with horizontal but also with orthogonal changes in reading direction.
• This study provides a unique, nonconfounded demonstration of perceptual span adaptability across different reading orientations.