I get these pulsing headaches that start from the base of my skull and reach my forehead. when i wear a neck collar they seem to get better. why?

It may be...: Muscle related, as the soft collar may take some of the tension off of your neck muscles. It's unlikely vascular as these type of very concerning headaches shouldn't necessarily improve with a neck collar. If the headaches persist, progress in pain, you develop nausea or vomiting or neurologic issues like vision changes, weakness or sensory changes then seek help urgently.