The pattern of intra-/inter-hemispheric interactions of left and right hemispheres in visual word processing

ABSTRACT

This study aimed to investigate the intra-/inter-hemispheric interactions during visual word processing, by manipulating stimulus onset asynchrony (SOA) in a primed-lateralized lexical decision task. To assess intra-/inter-hemispheric priming effects, identical prime-target pairs were presented in the same or opposite unilateral visual fields. The study found that the right visual field advantage (RVFA) was observed when Korean words were presented sequentially within hemispheres, indicating that the inherent characteristics of the two hemispheres, rather than differences in memory or linguistic aspects of lexical processing, contributed to the hemispheric asymmetry. Additionally, intra-hemispheric priming effects were symmetrical in both hemispheres, with similar increases in priming for words and nonwords from SOA 120 ms to SOA 600 ms. Furthermore, inter-hemispheric priming effects were asymmetrical, with stronger priming when stimuli were presented in a sequence of LH→RH than in RH→LH. These findings suggest that the intrinsic differences in lexical processing between the two hemispheres may be related to the asymmetric pattern of hemispheric interactions in visual word processing.

HIGHLIGHTS

• Left-superiority in lexical processing was maintained in sequential presentation.

• Recency memory of lexical processing does not lead to hemispheric asymmetry.

• Symmetrical pattern in intra-hemispheric repetition primings was shown.

• Asymmetry pattern in inter-hemispheric repetition primings was observed.

• Hemispheric asymmetry of lexical processing have relevance to these patterns.

KEYWORDS:

• Hemispheric asymmetry
• hemispheric coordination
• inter-hemispheric interaction
• visual word processing

Acknowledgments

The authors would like to thank all the participants in the present study as they had no problems with the experimental procedures.

Disclosure statement

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

Data availability statement

The collected and analyzed data in the present study are available after permission of the authors in case of acceptable requests.

Additional information

Funding

This work was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF-2022S1A5B5A16049384).