In a spinal turtle, unilateral stimulation in the rostral scratch receptive field elicited rhythmic fictive rostral scratching in ipsilateral hindlimb motor neurons; contralateral hip motor activity was also rhythmic and out-of-phase with ipsilateral hip motor activity. When left and right rostral scratch receptive fields were stimulated simultaneously, bilateral rhythmic fictive rostral scratc...

BACKGROUND Scratching in infants is considered to be related to early development of eczema. Little is known about the effects of maternal immune markers on scratching among infants. The objective is to compare the risks related to maternal serum immune markers (IMs) during pregnancy and IMs in breast milk for the occurrence of scratching in infants at 6 and 12 months of age. METHODS Pregnant...

Rostral segments of the spinal cord hindlimb enlargement are more important than caudal segments for generating locomotion and scratching rhythms in limbed vertebrates, but the adequacy of rostral segments has not been directly compared between locomotion and scratching. We separated caudal segments from immobilized low-spinal turtles by sequential spinal cord transections. After separation of ...

The influence of age on hindlimb scratching induced in rats by the serotonin agonist, 5-methoxytryptamine (5-MeOT), was studied. The 5-MeOT-induced scratching was strongest in 30-day-old rats and least in 90-day-old rats. Sex hormones do not play a role in these differences since treatment of young male rats with testosterone propionate did not change the scratching response. The same age depen...

Counterstimuli such as scratching, pinching, noxious heat and cold, and innocuous cooling and warming have been shown to inhibit itch in humans. In the present study, the effects of each of these counterstimuli were determined on baseline firing rates and on sustained pruriceptive responses of rat trigeminothalamic tract neurons. We found that scratching had little, if any, effect on baseline f...

Surfactants, an important component of cleansers, often cause itch in humans. Topical application of sodium laurate and N-lauroylsarcosine sodium salt to the skin of mice immediately (for 1-1.5 hours) increased scratching, and the former increased scratching again between 2 and 3 hours after application. Thus, we examined the mechanisms of sodium laurate-induced delayed scratching. Sodium laura...

Our experiments were conducted to determine whether substance P (SP) would elicit an itch sensation mediated by mast cells in mice. An intradermal injection of SP (10-135 microgram site-1) into the rostral back of the ICR mouse dose-dependently produced scratching of the injected site. The SP- (135 microgram site-1 = 100 nmol site-1) induced scratching was inhibited by capsaicin (repeated admin...

Does the spinal cord use a single network to generate locomotor and scratching rhythms or two separate networks? Previous research showed that simultaneous swim and scratch stimulation ("dual stimulation") in immobilized, spinal turtles evokes a single rhythm in hindlimb motor nerves with a frequency often greater than during swim stimulation alone or scratch stimulation alone. This suggests th...

This study of rhesus macaques (Macaca mulatta) investigated whether individual differences in emotionality, as measured by scratching frequencies, are stable over time and across seasons. Five adult females living in captive social groups were observed during two consecutive birth seasons and five females during the birth and the mating season. Scratching frequencies were higher during the birt...

People can hear a lot of information about an object by tapping and scratching it. We have developed a TapAndScratch node that automatically synthesises the sounds of tapping and scratching interactions with haptic objects in the Reachin haptic API. The scratching sounds are produced by a granular synthesis algorithm that is used to provide information about interactions with the surface of an ...