Letter rotations: through the magnifying glass and What evidence found there

ABSTRACT

Expert readers have a wide tolerance for distortions of the letters that make up a word. Nevertheless, the limits of this invariance are still under debate. To scrutinise this issue, we focused on a single parameter, letter rotation, as it serves to disentangle the predictions from neurally-inspired models of word recognition. Whereas the Local-Combination-Detector (LCD) model predicts invariance up to 45°, the SERIOL model predicts a linear cost until 60°. To test these predictions, Experiments 1 and 2 employed four rotation angles (0°, 22.5°, 45°, 67.5°) in lexical decision and semantic categorisation. The cost was minimal at 22.5°, sizeable at 45°, and considerably large at 67.5°. In Experiment 3, we focused on four moderate rotation angles (<45°). We found a gradual reading cost that increased at 45°. Thus, while there is a resilience limit around 45° favouring LCD, less steep angles also produce a reading cost, backing the SERIOL model.

KEYWORDS:

• Rotation
• letter detectors
• orthographic processing
• letter distorsion
• letter identity

Acknowledgments

This study was supported by the Spanish Ministry of Science and Innovation (grants PRE2018-083922, PSI2017-86210-P, and PID2020-116740GB-I00 [MCIN/ AEI/10.13039/501100011033]). We would like to thank Andrew Aschenbrenner and Melvin Yap for sharing their word and pseudoword stimuli with us.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Spanish Ministry of Science and Innovation: [Grant Number PID2020-116740GB-I00,PRE2018-083922,PSI2017-86210-P].