| Autonomic nervous system dysfunction characterized by sympathetic hyperactivity at rest and sympathetic hypo-reactivity to physical stressors has been demonstrated in individuals with fibromyalgia. However, little is known regarding the autonomic responses to mental stressors. This study investigated autonomic and subjective responses in 10 female fibromyalgia subjects and 10 age-matched female controls during a physical (active standing) and mental challenge (Stroop word task).; There were no group differences in autonomic measures at baseline. However, fibromyalgia subjects were more anxious, fatigued and in more pain. During the active stand task, fibromyalgia subjects had less increase in sympathetic and less decrease in parasympathetic modulations of heart rate compared to controls. However, during the cognitive challenge group differences were not observed in either autonomic or subjective responses. These results confirm previous findings that individuals with fibromyalgia are less reactive to physical challenges than controls, but also suggest that they do not respond differently during mental challenges. |
