Tired of the ridge that appears between scalp and forehead - what is it?

I've seen some people have this before, maybe we all do, but when I raise my eyebrows, a ridge forms between my forehead and scalp. I'm assuming it is scalp above the ridge. The shape is very odd and distinctive - a curved line that follows what would be my hairline (although it seems too low) but in the centre there is a curved dip.

I've tried to show it below:


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What is this ridge line? Why is there a circular part in the center that is lower?

Any ideas?

Well, I've done a little research and its the Galea. Looking at photos, the difference between the two is far stronger with me.

Something to do with calcification I believe. Even non balders have it. Trust me man, I have like one center ridge and two on the sides of my entire forehead. It's really boney looking but isn't as noticeable as you may think.

Whatever it is, it is annoying. Is the hairline supposed to start at this ridge - it seems a little low to me...

i believe that this is where you juvenile hairline was, and everyone recedes half an inch or so, even non balders, when the mature hairline appears.