A new article in the ICA Journal by Thomas R. Coyle explores the development of intraindividual differences in cognitive abilities, called “tilt.” The findings show the importance of understanding people’s relative strengths and weaknesses.
Coyle investigated the relative strengths of adolescents’ mechanical, spatial, and academic strengths (or weaknesses). Among his findings:
Sex differences were larger for mechanical tilt, with more males showing a relative strength in mechanical abilities (compared to academic abilities). But for spatial tilt, there were “negligible” sex differences.
Processing speed and general intelligence (g) were important in developing mechanical tilt. The influence of processing speed and g were stronger for males than females.
Sex differences in spatial tilt do not increase with age, indicating that the maturation and education processes do not have an impact on the relative #'s of males and females showing greater spatial tilt.
The results were generally supporting of investment theory, which is that individuals’ strengths are (partially) a product of what they invest their time into learning. It also supports cascade theory, which states that the development of tilt is mediated by both g and processing speed (not just speed).
In the real world, this study has some implications because relative strengths and weaknesses are very common. This study shows that, to a degree, tilt may be malleable. In other words, it may be possible to work on your weaknesses and bring them closer to your typical cognitive ability level. It also raises the possibility that schools could see academic benefits from training students’ spatial abilities, which are important for many STEM fields and vocations.
The finding that mechanical tilt shows increasing sex differences with age while spatial tilt doesn’t is really interesting. It suggests that mechanical abilities are more influenced by socialization, practice, and investment (boys spend more time tinkering with mechanical things), while spatial abilities develop more uniformly across sexes. The processing speed and g mediating mechanical tilt development shows that higher cognitive ability lets you learn mechanical skills faster, which creates a feedback loop where smarter kids invest more in mechanical activities because they’re rewarding. This supports the idea that cognitive profiles aren’t just innate but develop through interaction between ability and experience.
The malleability of tilt has practical implications. If someone has weak spatial ability relative to their verbal/academic skills, targeted practice could reduce that gap. This matters for STEM fields where spatial reasoning is crucial but often undertrained in schools. The sex differences in mechanical tilt being driven by investment rather than biology suggests that girls’ underrepresentation in mechanical fields is partly about opportunity and encouragement, not fundamental cognitive differences. Schools could close these gaps by providing equal exposure to mechanical and spatial learning activities early in development when tilt is still forming.
Sex differences were larger for mechanical tilt, with more males showing a relative strength in mechanical abilities (compared to academic abilities). But for spatial tilt, there were “negligible” sex differences.