Patterns of language and visuospatial functional lateralization and cognitive ability: a systematic review

ABSTRACT

For most individuals, language is predominately localized to the left hemisphere of the brain and visuospatial processing to the right. This is the typical pattern of functional lateralization. Evolutionary theories of lateralization suggest that the typical pattern is most common as it delivers a cognitive advantage. In contrast, deviations from the typical pattern may lead to poorer cognitive abilities. The aim of this systematic review was to assess the evidence for an association between patterns of language and visuospatial lateralization and measures of cognitive ability. We screened 9,122 studies, retrieved from PsycINFO, EMBASE, MEDLINE, PubMed, and Web of Science. The 17 studies that met our selection criteria revealed little evidence for an advantage of typical compared to atypical patterns of lateralization, although atypical lateralization patterns were related to worse language comprehension, spatial ability, and reading, but further research is needed to confirm this. We conclude with recommendations that future researchers recruit larger samples of atypical participants, and consider strength of lateraliation and bilaterality when analysing functional lateralization patterns.

KEYWORDS:

• Lateralization
• language
• visuospatial processing
• cognitive ability
• review

Acknowledgements

We would like to thank Selma De Jesús-Zayas, Selene Petit, and Deborah Serrien for sharing their manuscript/datasets with us. We would also like to thank the members of the laterality researchers’ email group, especially Megan Bartlett and Sanne Brederoo, for their help in sourcing particularly hard-to-find studies. This research was carried out while the first author (JEQC) was in receipt of “The Dr Peter Livesey Award” at The University of Western Australia.

Disclosure statement

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

Data availability statement

This is a systematic review which has not generated any raw data.

Additional information

Funding

This research is supported by an Australian Government Research Training Program (RTP) Offset under [grant number 10306140].