Publications by authors named "Robert W Dykes"

Following amputation, most amputees still report feeling the missing limb and often describe these feelings as excruciatingly painful. Phantom limb sensations (PLS) are useful while controlling a prosthesis; however, phantom limb pain (PLP) is a debilitating condition that drastically hinders quality of life. Although such experiences have been reported since the early 16th century, the etiology remains unknown.

View Article and Find Full Text PDF

We describe a novel stimulus delivery system designed to present tactile stimuli to a subject in the tunnel of a magnetic resonance imaging (MRI) system. Using energy from an air-driven piston to turn a wheel, the device advances a conveyor belt with a pre-determined sequence of stimuli that differ in their spatial features into the tunnel of the MRI. The positioning of one or several stimulus objects in a window near the subject's hand is controlled by a photoelectric device that detects periodic openings in the conveyor belt.

View Article and Find Full Text PDF

Application of cold stimuli to the sentient portion of the anterior torso of 12 spinal-cord-transected individuals (patients) and to comparable sites of 11 control participants showed that thresholds are lower for women than for men and that the difference between the sexes is maintained following spinal-cord transection. Patients of both sexes were more sensitive to cold stimuli than were controls. Estimates of stimulus intensity showed that participants reliably distinguished the 3 cool stimuli but that control women offered significantly larger estimates than control men.

View Article and Find Full Text PDF

Background: This study compared the neural structures found in grafted skin of burn survivors with neural structures found in site-matched normal skin and correlated these structures with psychophysical measures of sensation.

Methods: Fifteen skin-grafted male burn survivors (47.7+/-10.

View Article and Find Full Text PDF

The threshold to warming was measured at 10 sites on the anterior torso between the umbilicus and the clavicle of normal and spinal-cord transected individuals. In normal individuals, thresholds were higher on the thorax than on the abdomen. Men had higher and more variable thresholds than women.

View Article and Find Full Text PDF