Nociception and/or the sensation of pain is essential for the survival of the organism. Just as important are the antinociceptive mechanisms that reduce the nociceptive input and perceived pain. Without such mechanisms, it would be impossible to turn one’s focus away from even the most minor painful stimulus. The balance between excitatory and inhibitory functions in nociception is intricate an...

It is suggested that the autonomic response to noxious stimulation may be measured during anaesthesia. The response may be marked despite considerable depression of cortical activity as measured by the cerebral function monitor. Preliminary results suggest that large doses of narcotic analgesics reduce the autonomic response to noxious stimulation and this may be used as a test to compare the p...

the purpose of the this study was to investigate the effect of direct current on montoneuron reflex exitability. thirty six subjects (18 males, 18 females) 19.36 years of age ( x= 24.06, sd= 3.63) participated in this study. the reflex excitability of soleus motoneruons was assessed by measuring the amount of change in the peak to peak ampitude of the h-reflex before and after direct current wa...

To highlight the effects of hypnotic focused analgesia (HFA), 20 healthy participants underwent a cold pressor test (CPT) in waking basal conditions (WBC) by keeping the right hand in icy water until tolerable (pain tolerance); subjective pain was quantified by visual scale immediately before extracting the hand from water. The test was then repeated while the participants were under hypnosis a...

purpose: to evaluate the incidence of the oculo-cardiac reflex (ocr) and its associated risk factors during strabismus surgeries performed at a tertiary referral center between 1390 and 1392. methods: over a 2-year period, all strabismus surgery candidates were enrolled in the study after obtaining consent from the patients or their parents. vital signs were recorded before the initiation of th...

Until recently, dishabituation and sensitization have commonly been considered to reflect a unitary process: Sensitization refers to a general facilitation produced by strong or noxious stimuli that enhances subsequent responding; dishabituation has been thought to represent a special instance of sensitization in which the facilitation is simply superimposed on a habituated response level. The ...

This review considers recent research assessing psychophysiological reactivity to fear imagery in anxiety disorder patients. As in animal subjects, fear cues prompt in humans a state of defensive motivation in which autonomic and somatic survival reflexes are markedly enhanced. Thus, a startle stimulus presented in a fear context yields a stronger (potentiated) reflex, providing a quantitative ...

Habituation, one of the simplest behavioral paradigms for studying memory, has recently been examined on the cellular level in the gill-withdrawal reflex in the mollusc Aplysia and in the escape response in cray-fish. In both cases short-term habituation involved a decrease in excitatory synaptic transmission at the synapses between the sensory neurons and their central target cells. To analyze...

Non-invasive, weak direct current stimulation can induce changes in excitability of underlying neural tissue. Many studies have used transcranial direct current stimulation to induce changes in the brain, however more recently a number of studies have used transcutaneous spinal direct current stimulation to induce changes in the spinal cord. This study further characterises the effects followin...

We have previously demonstrated a decrease in baroreceptor discharge sensitivity in dogs with experimental heart failure. In the present study, we determined the sensitivity of the carotid sinus baroreceptor reflex in dogs with pacing-induced heart failure. The carotid sinus baroreceptor reflex sensitivity was determined by pressurizing one carotid sinus with all other baroreceptor and cardiopu...