tex mode sub- and super-scripts

[Mark Alford]

I just upgraded to Fedora 7, which means I got upgraded from
emacs-21 to emacs-22. Now I find that when I edit a TeX file,
all subscripts (TeX _{xxx}) and superscripts (TeX ^{xxx})
are rendered in small type, lowered or raised on the line.

Since TeX is a markup language not a WYSIWYG application
this is not helpful to the readability of the TeX source.

How do I switch off this new behavior, while keeping the syntactic
color highlighting (font lock) that is helpful when composing TeX?