Dear Foggy,
You are not alone. Feeling fuzzy is a common symptom when there is tension on the joints and connective tissues of the head and upper neck. Your brain is being deprived of glucose and oxygen in the blood and the electrical impulses that run the brain from that same tension that is causing those knots that you feel between your head and neck. This kind of stress can through off the hormones that handle stress throughout your body and can definitely affect your sleep.
Specific Upper Cervical Chiropractic adjustments, no twisting or cracking, can reduce this stress, improve blood flow to the brain and help your body's hormones self regulate again. Look for an Upper Cervical Chiropractor for the best results.

Thomas Polucki