“According to some theorists (e.g. Anderson 2001), information processing speed forms the basis of individual differences in IQ. [...] Inspection time among individuals with autism has been reported to be (i) much better than expected, based upon measured IQ, (ii) equal to that of a typically developing group with mean IQ scores 25 points higher...”
According to some theorists (e.g. Anderson 2001), information processing speed forms the basis of individual differences in IQ.
My understanding is that information processing time (as measured by reaction time) is pretty standard across humans, and pretty close the physical limits of neurons.
It is true that reaction time correlates with IQ, but that is a bit misleading. Average reaction time correlates with IQ, but every person’s best case reaction time is about the same. It seems that the the correlation with between average RT and IQ is mediated by better vigilance. That is, people with higher IQs are able to score better on RT tasks because they are able to maintain their attention on the task (and therefore maintain an RT closer to their best), for longer periods.
I’m somewhat suspicious that this is an artifact of the way we usually measure IQ since tests often look like “more IQ for more questions answered correctly in a fixed amount of time”, so unless we really mean to include speed in our measures of g, this seems possibly spurious.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2677588/
“According to some theorists (e.g. Anderson 2001), information processing speed forms the basis of individual differences in IQ. [...] Inspection time among individuals with autism has been reported to be (i) much better than expected, based upon measured IQ, (ii) equal to that of a typically developing group with mean IQ scores 25 points higher...”
Note 1: Lightly edited to remove acronyms.
Note 2: !!!! Whoa.
My understanding is that information processing time (as measured by reaction time) is pretty standard across humans, and pretty close the physical limits of neurons.
It is true that reaction time correlates with IQ, but that is a bit misleading. Average reaction time correlates with IQ, but every person’s best case reaction time is about the same. It seems that the the correlation with between average RT and IQ is mediated by better vigilance. That is, people with higher IQs are able to score better on RT tasks because they are able to maintain their attention on the task (and therefore maintain an RT closer to their best), for longer periods.
My citation is chapter 3 (?) of this textbook.
I’m somewhat suspicious that this is an artifact of the way we usually measure IQ since tests often look like “more IQ for more questions answered correctly in a fixed amount of time”, so unless we really mean to include speed in our measures of g, this seems possibly spurious.