Spinal neurons processing information from the ureter have been characterized in rats 1-4 days after the implantation of an experimental ureteric stone and compared with those of normal rats. The effects of a conditioning noxious stimulation of the ureter in the presence of the hyperalgesia evoked by the calculosis also were examined. Extracellular recordings were performed at the T12-L1 segmen...

Serotonin (5-HT) plays an important role in sensitization of defensive reflexes in Aplysia, and is also involved in several aspects of arousal, such as the control of locomotion and of heart rate. In the preceding paper, we showed that tail-nerve shock, a noxious stimulus that readily induces sensitization, increases the firing rate of a large number of serotonergic neurons throughout the centr...

PURPOSE To characterize human corneal psychophysical channels. METHODS Twenty subjects participated in this study. A Belmonte pneumatic esthesiometer was used to deliver stimuli, and the ascending method of limits and the method of constant stimuli were used to estimate thresholds. Sensation was characterized for different stimuli. Corneal mechanical and chemical thresholds were measured at d...

Nociception is the detection of a noxious tissue-damaging stimulus and is sometimes accompanied by a reflex response such as withdrawal. Pain perception, as distinct from nociception, has been demonstrated in birds and mammals but has not been systematically studied in lower vertebrates. We assessed whether a fish possessed cutaneous nociceptors capable of detecting noxious stimuli and whether ...

We use a novel balanced experimental design to specifically investigate brain mechanisms underlying the modulating effect of expected pain intensity on afferent nociceptive processing and pain perception. We used two visual cues, each conditioned to one of two noxious thermal stimuli [ approximately 48 degrees C (high) or 47 degrees C (low)]. The visual cues were presented just before and durin...

This article deals with the construction of the "insect" ethnozoological dominium by the inhabitants of Tapera County, which is located in the municipality of São Gonçalo dos Campos, Bahia State. Data were obtained from March to May 2005 through open-ended interviews carried out with 23 men and 8 women, whose ages ranged from 6 to 66 years old. Interviewees were asked about how they perceived a...

OBJECTIVE This study examined modulation of trigeminal pain/nociception by 2 supraspinal mechanisms: emotional controls of nociception and diffuse noxious inhibitory controls. BACKGROUND Prior research suggests emotional picture viewing (emotional controls) and tonic noxious stimuli (diffuse noxious inhibitory controls) engage supraspinal mechanisms to modulate pain and nociceptive processes....