Good Illustration of My Third Law of the Behavioral Genetics Fallacy

 This study is a good example of my Third Law of the Behavior Genetic Fallacy:

Differences in human behavior, intelligence and personality are not accounted for by structural or functional differences in the brain.

 The lengthy title of the study captures it, I think:

Hippocampal grey matter tissue microstructure does not explain individual differences in hippocampal-dependent task performance

This study used MRI's to measure hippocampal size and then see if a bigger hippocampus correlated to "...scene imagination, autobiographical memory recall, future thinking and spatial navigation..." which "... have long been linked with hippocampal structure in healthy people, although evidence for such relationships is, in fact, mixed. " Well, mixed no longer, I hope. Nevertheless, there was an illusion of "evidence" up to that point, where one could tout such nonsense as fact. This is what I like to call the shell game of false positives, in which a study purports to show something, does not replicate, but by that time, they have some new studies to hang their hats on. 

People don't need a big hippocampus. The idea is ludicrous on its face and the use of MRI's to measure brain sizes is little more than high tech phrenology.