Lightroom :: Develop Module Controls Missing?

I don't know how I did it, but the controls on the window in the develop module for exposure, contrast, clarity, black, white points etc are gone. I cannot currently adjust them for overall image edit. They only pop up if I use the gradient tool etc.  I don't know what I did that they are missing.  how to get them back on the panel.  These are the controls above the curve that let you adjust for overall edits not the tool specific ones.