I have noted that journals and newspaper put their articles into
columns, and that often, reports, are not put into columns.  I imagine
that journals and newspapers use columns in their layout for various
reasons.  My question is what cognitive pyschology research shows
regarding what the best column width is for ease of reading and
optimum comprehension.

Hi, prometheus-u, I'm interested in this question too.  Are you
thinking about print only, or are you also asking about length of line
on web pages?  And are you expecting to see an answer expressed in
terms of inches (or picas) or, say, number of characters of a certain
size?

Your name makes me think of a very long, difficult paper I wrote for a
class called Romantic Poets when I was a junior in college.

Archae0pteryx

I was thinking of the "written" word, whether it be presented as
ink-stained wood pulp (print) or electronically, as in the web.  I was
expecting to see the answer expressed in terms of physical width
(incdes, picas, cm) or in terms of a number of words or
chaacters...either would be OK, both would be ideal.

The question behind the question is how to best present written
material to make it easiest for the reader.

Here's some reading that will help answer your question:

http://desktoppub.about.com/cs/finetypography/ht/line_length.htm
http://www.ronreason.com/personal/bodytext.html
http://english.unitecnology.ac.nz/resources/resources/exp_lang/print.html