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We have previously shown that sinusoidal galvanic vestibular stimulation (sGVS), a means of a selectively modulating vestibular afferent input without affecting other inputs, can cause partial entrainment of muscle sympathetic nerve activity (MSNA). Given that motion sickness causes sweating and pallor, we tested the hypothesis that sGVS also entrains skin(More)
We have previously demonstrated that selective modulation of vestibular inputs, via sinusoidal galvanic vestibular stimulation (GVS) delivered at 0.5-0.8 Hz, can cause partial entrainment of muscle sympathetic nerve activity (MSNA). Given that we had seen interaction between the dynamic vestibular input and the normal cardiac-locked MSNA rhythm, we tested(More)
We tested the hypothesis that vestibular and cardiac rhythms compete to modulate muscle sympathetic nerve activity (MSNA) in human subjects. Sinusoidal galvanic vestibular stimulation was applied across the mastoid processes at each subject's cardiac frequency and at ±0.1, ±0.2, ±0.3 and ±0.6 Hz. Cyclic modulation of MSNA was weakest at this central(More)
Blood pressure is controlled on a beat-to-beat basis through fluctuations in heart rate and the degree of sympathetically-mediated vasoconstriction in skeletal muscles. By recording muscle sympathetic nerve activity (MSNA) at the same time as performing functional magnetic resonance imaging (fMRI) of the brain, we aimed to identify cortical structures(More)
In thermoneutral conditions resting skin sympathetic nerve activity (SSNA) is related to the level of arousal and emotional state. The brain regions responsible for the generation of spontaneous SSNA are not known. In the present study we used concurrent recordings of SSNA and brain activity in awake humans to identify cortical and subcortical areas(More)
The sympathetic innervation of the skin not only primarily subserves thermoregulation, but has also been commandeered as a means of emotional expression. While the majority of brain imaging studies of emotion have utilised the galvanic skin response as a means of inferring changes in skin sympathetic nerve activity (SSNA), spontaneous fluctuations in the(More)
Studies previously performed in our laboratory have shown that sinusoidal galvanic vestibular stimulation (sGVS), a means of selectively modulating vestibular input without affecting other inputs, can cause partial entrainment of muscle sympathetic nerve activity (MSNA) at frequencies ranging from 0.2 to 2.0 Hz. Here we test the effect of sGVS on(More)
Experiments were conducted to determine whether bladder cancer would develop in primates (Papio sp.) infected with S. haematobium and concurrently exposed to low initiating doses of the bladder carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). To control for the systemic effects of schistosomiasis, 5 baboons were infected with S. mansoni, which does(More)
The sympathetic innervation of the skin primarily subserves thermoregulation, but the system has also been commandeered as a means of expressing emotion. While it is known that the level of skin sympathetic nerve activity (SSNA) is affected by anxiety, the majority of emotional studies have utilized the galvanic skin response as a means of inferring(More)
The sympathetic nervous system subserves many of the autonomic responses to mental stress and emotional processing. While peripheral markers of sympathetic activity can be obtained indirectly - by measuring heart rate, blood pressure, sweat release and skin blood flow - these effector-organ responses are slower compared to the directly recorded sympathetic(More)