That seems a reasonable approximation from my perspective as a layman. A couple of things (that I am sadly lacking sources for right now) that might suggest this interpretation include:
- there is a meaningful (albeit small) correlation between IQ and reaction times
- people with higher IQs show lower brain activation when performing cognitive tasks compared to people with lower IQs. That is, their brain has to do less work to perform the same task.
- there is a meaningful (albeit small) correlation between IQ and reaction times
- people with higher IQs show lower brain activation when performing cognitive tasks compared to people with lower IQs. That is, their brain has to do less work to perform the same task.