Potencial de transformação da dor pela cor: modulação da nocicepção por espectro de luz visível

Abstract

The painful experience is complex, individual and unpleasant for individuals, which is why it is of interest in the health sector to search for new methods of pain control. Therefore, the present review aimed to uncover, based on scientific evidence, whether colors (visible light spectrums) have a modulating effect on nociception. This study is a narrative review of the literature based on articles found in the Pubmed and Scielo databases. The results found in the literature reveal that colored stimuli can cause both analgesia and hypersensitivity, depending on the wavelength, intensity and route of exposure. Studies have shown that green light was able to reduce painful experiences and migraine episodes, which shows that this spectrum can have an antinociceptive effect. On the other hand, other studies demonstrated that red light was capable of producing thermal hyperalgesia and generalized mechanical allodynia in rats; and blue light was the one that caused the greatest activation of brain areas related to pain processing, revealing a pro-nociceptive effect of both spectrums. The mechanisms behind these effects are not yet well known, however the literature describes that colored stimuli can modulate nociception through the visual system, through the action of cones and CGRIFs, and through the descending modulator system in the MVR. Furthermore, other authors have described the indirect influence of color on pain, mediated by emotional states of excitement and attention, produced through learned associations. The findings of this review open new perspectives for future research that explores the use of colors in the context of healthcare, aiming to develop innovative approaches to treating patients. However, the relationship between color and pain is complex, and involves aspects from different areas, such as Psychology, Medicine, Chromotherapy, which reveals the need for integration of multidisciplinary data, with collaboration between specialists from different fields to develop new conceptions about this relationship