On the relationship between executive functions and the basic ability and item-position components of fluid intelligence measures

Accumulated evidence indicates that fluid intelligence tests are not pure measure of general ability, but at least partly reflect a systematic variation associated with the item position, which has been coined as the... [ view full abstract ]

Accumulated evidence indicates that fluid intelligence tests are not pure measure of general ability, but at least partly reflect a systematic variation associated with the item position, which has been coined as the item-position effect (Schweizer, Troche, & Rammsayer, 2011). Therefore, previous findings regarding the relationship between executive functions (EFs) and general fluid intelligence represented by the test scores deserve further scrutiny. The aim of the current study is to provide new insight into the relationship between EFs and fluid intelligence in considering the item-position effect observed in fluid intelligence tests. Data were collected from 205 university students. Raven's Advanced Progressive Matrices (APM) and Horn’s LPS reasoning test were used to assess fluid intelligence. A battery of six cognitive tasks was administered to tap updating, shifting and inhibition. Fluid intelligence showed substantial correlations with the updating and inhibition processes but no correlation with the shifting process without considering the item-position effect. Next, the fixed-link model was applied to APM and LPS data separately to decompose them into an ability component and an item-position-effect component. The results of relating three EFs to the two components of fluid intelligence tests showed that the updating and shifting processes mainly related to the position- effect component whereas the inhibition process was associated with the ability component. These findings suggest that the updating and shifting processes may play a role in facilitating the use of rules to improve performance during the course of completing intelligence tests while inhibition is important for intelligence in general.