Why is working memory related to intelligence? Different contributions from storage and processing

Abstract

Domain-specific contributions of working memory (WM), short-term memory (STM), and executive functioning (EF) to individual differences in intelligence were analysed using a latent variable approach. A sample of 345 participants completed a battery of 24 tests tapping the constructs of interests as comprehensively as possible. Visuospatial and verbal STM and WM tasks were administered along with three subcomponents of EF, namely inhibition, planning, and shifting. Intelligence was assessed by non-verbal/abstract/fluid intelligence (Gf) and verbal/crystallised intelligence (Gc) standardised tests. Structural equation modelling results show that EF is the main predictor of Gf, whereas verbal STM is the main predictor of Gc. Storage and processing providing different contributions to the prediction of Gf and Gc supports the view that both short-term storage and executive functioning account for the relationship between WM and intelligence. This main conclusion stresses the importance of acknowledging core cognitive constructs as being hierarchical systems with general and domain-specific mechanisms.

Keywords:

• Working memory
• Short-term memory
• Executive functioning
• Fluid intelligence
• Crystallised intelligence

The authors would like to thank Ya-Nan Wang, Jun-Kai Yang, Liang Liang, and Yu-ling Zhou for their kind assistance in recruiting participants and conducting the study, and En-Guo Wang and Xiao-Jiang Zhang for software support.

The authors would like to thank Ya-Nan Wang, Jun-Kai Yang, Liang Liang, and Yu-ling Zhou for their kind assistance in recruiting participants and conducting the study, and En-Guo Wang and Xiao-Jiang Zhang for software support.

Notes

¹ Memory Span and Executive Functioning Measurement Software was designed by a research team in the Cognitive Neuroscience Lab of Nanjing Normal University in China, including Chang Liu, Cai-Ping Dang, En-GuoWang, Xiao-Jiang Zhang, Hui-Ling Tang and Yun Tian.

Additional information

Funding

Funding: This research is supported in part by grants from the National Natural Science Foundation of China (30200082), Distinguished Young Talents in Higher Education of Guangdong, China (B103006, and the 12th Five-Year Project in Philosophy and Social Sciences' Development of Guangzhou, China (11Y91).