Changing the world reference changes the axis labels to match that world reference, but you can always change the labels back.
xlabels=get(gca,'XTickLabels'); % //this will get your current labels;
nlabels=length(xlabels); % //Get how many we need
new_xlabels=linspace(-1,1,nlabels); % //Create a linear space at each label point
set(gca,'XTickLabels',new_xlabels); % //apply the new labels