INTRODUCTION: Despite being considered least important for clinical practice in the pyramid of evidence for recommendations, sometimes scientists' expert opinions could help to better understand the summarization of updated publications. OBJECTIVE: To provide a major summarized update about brain imaging and stimulation of the nervous system in health and disease. METHODS: Comprehensive review developed by experts in each subarea of knowledge in neuroimaging and non-invasive stimulation of the nervous system. A team of researchers and clinic experts was invited to present an update on their area of expertise. RESULTS: In basics on brain imaging techniques, we approach general and quantitative electroencephalography, functional magnetic resonance imaging, functional near-infrared spectroscopy, and experimental paradigms in brain imaging studies. Were included associations between transcranial magnetic stimulation and electromyography, electroencephalography, and functional near-infrared stimulation to evaluate brain activity. Furthermore, we showed several actualized central and peripheral neuromodulation techniques. And finally, we presented different clinical and performance uses of non-invasive neuromodulation. CONCLUSION: To our knowledge, this is a major summarized and concentrated update about brain imaging and stimulation that can benefit neuroscience researchers and clinicians from different levels of experience.

BACKGROUND: Chronic pain is one of the most common symptoms of temporomandibular disorders (TMD). Although its pathophysiology is still a challenge, TMD has been associated with changes in central nervous system activity related to pain modulatory capacity. OBJECTIVE: To assess the cortical activity of patients with temporomandibular disorders and chronic pain of myofascial origin using quantitative electroencephalography (qEEG) in different mental states. METHOD: This study consists of a cross-sectional study. Individuals with TMD and chronic pain and healthy controls were evaluated using qEEG in four consecutive conditions, all with closed eyes: 1) initial resting condition; 2) non-painful motor imagery task of hand movement; 3) painful motor imagery task of clenching the teeth; 4) final resting condition. RESULTS: Participants with TMD and chronic pain overall presented decreased alpha power density during baseline at rest, non-painful and painful motor imagery tasks when compared to healthy controls. Furthermore, functional brain connectivity was distinct between groups, with TMD and chronic pain showing lower small-world values for the delta (all conditions), theta (painful and non-painful motor imagery task), and alpha bands (painful motor imagery task), and an increase in the beta band (all conditions). CONCLUSION: These results suggest that TMD and chronic pain could be associated with maladaptive plasticity in the brain, which may correspond to a reduced ability to modify brain activity during different mental tasks, including painful and non-painful motor imagery.