[Auricular electrodermic reflex in humans: experimental study].

Abstract

Several sets of experiments have been performed for the following purposes: 1) to show that spontaneous pain as well as thermalgesic stimuli provoke the auriculoelectrodermic reflex (AER); 2) to investigate the action of local, general and rachianaesthesia on the AER, and 3) finally, to know the afferent, efferent and spinal pathways of the AER. As painful stimulus was utilized noxius heat (45 degrees C during 30 seconds) and the AER wss registered by means of a Servoscope (Sedatelec). Local and rachianaesthesia suppressed the AER but the general anaesthesia decreased only its intensity. The study of the AER in paraplejic patients revealed that the thermalgesic impulses responsible for the AER, enter in the spinal cord not only through the dorsal root corresponding to the stimulated dermatome, but also through the 4-5 cranealer roots. On the other hand, the intraspinal pathway of the AER impulses is bilateral, with a slight ipsilateral predominance. The polyradicular input and spinal bilaterality difference the thermalgesic from the other nociceptive impulses. The results obtained in tetralejic patients allow to conclude that the integration of the AER is spinal, corresponding to the supraspinal centres a modulatory influence.