Effects of Heat-evoked Experimental Pain on Brain Connectivity

Abnormal connectivity patterns interfere with the normal function of a given neuronal network, thus leading to circuit dysfunction and, subsequently, chronic pain. In the last few years, neuroscience has been heavily influenced by network science. This synergistic association provided a new framework for understanding brain function in health and how dysfunction in specific neuronal brain circuits can lead to symptoms. A network comprises nodes (e.g., areas of the brain) and edges (functional connections between nodes). An effective network can process and share large amounts of information while maintaining specificity and not allowing noise to contaminate the flow of information across the circuits. The network approach to brain functioning has been able to integrate what has been known for several decades as spatial structural anatomy with the time-varying streaming of information (connectivity) in a dynamic perspective. In this context, symptoms of diseases are seen as being correlated with specific network abnormalities, and therapeutic interventions as being associated with the normalisation of these abnormal patterns of connection. This study will investigate the responses of specific neuronal brain circuits to experimental heat pain in healthy volunteers. It has been hypothesised that the local-to-global connectivity pattern obtained by the stimulation of different cortical hubs (e.g., the primary motor and dorsolateral prefrontal cortices) will be described by TMS-EEG responses in healthy individuals, and the modification in cortical connectivity in experimental models will be described and compared it with a non-painful sensory stimulation of the same salience.