On Mon, 09 Aug 2010 22:25:36 -0700, John Higdon wrote:

That "purchasing habits are well-established by age 50" is the most
ridiculous nonsense I have ever heard in my life.

Not necessarily brands, but the type of products which you buy.

You are still buying automobiles, but it is unlikely that you
are now going to start buying hang-gliders.

Indeed. When one turns fifty, his brain does not turn to mush (I should
hope not: fifty is but a fond distant memory).

The brain starts turning to mush as soon as it stops getting used
on a regular basis. Many people never start using it, so the effect
is accelerated in them with aging.