Stress is factor that complicates many conditions including concussion. There are many ways one can improve this. Check out these resources.
1. Clark, David. They Can’t Find Anything Wrong!: 7 Keys to Understanding, Treating, and Healing Stress Illness. www.stressillness.com
2. Eimer, Bruce. Hypnotize Yourself Out of Pain Now!: A Powerful User-friendly Program for Anyone Searching for Immediate Pain Relief . Crown House Publishing, 2008.
3. Martha Davis, Elizabeth Robbins Eshelman and Matthew McKay. The Relaxation and Stress Reduction Workbook, 6th ed. New Harbinger Publications; 6th ed. edition (April 15 2008)
1. Breathe2Relax (Free).
Dr. Dawn Buse: Relaxation exercises that can be download for free.