I can give you some links about the c1/c2 {atlas & axis} adjustments and the symptoms if out of adjustment.

Chiropractic care info- a good one can help with many symptoms:
http://www.upcspine.com/self.htm
http://www.uppercervical.org/subpag...b/about_faq.php
http://www.spineuniverse.com/index.html
http://www.coloradochiropractic.org/.../glossary.html

pressure ridges-
I know I get lumpy & sore spots that come and go on my scalp- for me it's all related to how tense/tight my neck muscles get.