The objective of this study is to measure sympathetic nervous system function and stress
responses in patients with clinically documented and self-reported chronic fatigue that is
worsened by stress, compared to healthy controls. Baseline norepinephrine (NE) levels and
stress-induced NE levels in patients who fulfill criteria for Chronic Fatigue Syndrome (CFS)
and who self-identify with stress induced worsening fatigue, will be compared to data from
normal individuals pre and post-stress.