Change XCode "half page" scrolling behaviour?

[Gilles Kohl]

Dear All,

I was wondering if there is a way to change the "move half page
forward" scrolling behaviour the XCode editor exhibits when I cursor
down on the last line in the edit window - can it be changed to a
"scroll single line up"?

(The default behaviour rather confuses me as it creates an annoying
temporary loss of context for the eye)

Regards,
Gilles.