Past and present of mapping brain connections

This chapter reviews the history of brain connectivity research, from early theoretical models to modern neuroimaging techniques. Following an historical perspective, early theories, seminal discoveries, debates, and technological breakthroughs are described, showing how different ideas have shaped the field of brain connectivity. Starting from early philosophical theories on the origins of mental faculties, the chapter moves through history showing the impact of the early microscopic investigation, cortical localization, and the first electrophysiological experiments. An important role is also given to clinical studies that have led the way for disconnection syndromes and large-scale models of brain networks. Moreover, the introduction of tract tracing in animal models has significantly expanded the understanding of brain connectivity and networks, but it has also been revealed that advanced functions can only be understood by looking at the human brain. Today, modern neuroimaging has started to shed new light on this and, while many questions remain unanswered, neuroimaging has become an essential tool for both neuroscience research and clinical applications. As the field of brain connectivity research continues to evolve, it becomes increasingly evident that novel methodologies are essential for gaining deeper insights into the complexities of the brain and its intricate network of connections.