Avaliação da resposta cerebral a estímulo térmico não doloroso em regime permanente

Abstract

Temperature perception happens due to the capacity of specific afferent fibers - thin fibers - to conduct information about cold and heat, painful or not. Many peripheral neuropathies begin with the progressive destruction of these fibers, and therefore, the understanding of this process, from the stimulus transduction to the cortical response, is fundamental. There is already some knowledge about pain perception, however, there is a lack of information in the literature about the cortical processing of non-painful thermal stimuli. In this work, we analyzed the electroencephalographic signal of two experimental groups with different protocols of non-painful thermal stimulation. Seeking to investigate how brain regions are connected during these stimuli, the signals were processed using Magnitude Squared Coherence (MSC). A synchronism between the hemispheres in the frontal and parietal regions during thermal stimulation was found in the delta band. Within hemispheres, the frontal, parietal and central regions also presented higher coherence during stimulation for this band. No significant difference was found between heat and cold MSC values. The present work consolidates and contributes information for a better understanding of brain functioning during non-painful thermal stimulation.