Optical Measurements of the Skin Surface to Infer Distinctions in Myofascial Tissue Stiffness

Inclusion Criteria: * Healthy or diagnosed with benign, non-vascular headache and associated cervical musculoskeletal dysfunction (e.g. tender spots, trigger points, stiffness. * Adult male and female. Exclusion Criteria: * Migraine headaches. * Known cardiovascular, pulmonary, or metabolic disease. * Any co-morbidities that could contribute to back or neck pain (e.g., head trauma, cancer, seizures, tumors, radiculopathies, rheumatoid arthritis, systemic auto-immune or inflammatory conditions).