This is a good overview, but I don't think the proposed explanation is
very convincing. It's not clear to me how television and especially
pictures can be said to enrich the viewing environment. We see images
every time we open our eyes which are every bit as rich as any picture,
if less artistic. And we certainly see things move for many hours every
day, so old-fashioned television hardly adds much more stimulation.
I could see the case with video games, but those are hardly more than
a decade old. Did we really think that young people were better at
watching TV than grandpa?
Even if TV could add stimulation, it only became popular in the 1950s, and
the effect appears to go back at least to the 1930s or so. I really can't
buy the claim that people putting more pictures on the wall back then made
a difference.
Here are a couple of postings I made to the list when we first discussed
this. The first one was meant to be flippant but comes off a bit snide,
I'm afraid. I got carried away by my excitement at the discovery and its
potential implications. I have some other postings by other people on
the topic, including Ian Goddard (who attributes it to Rupert Sheldrake's
morphic resonance!), Robin Hanson, Marvin Minsky (who suggests family
size changes), and Hara Ra, who produced an explanation in terms of
sensory stimulation rather similar to that in the referenced article.
Hal
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