What Conscious experiences normally result from the flow of external input into our sensory systems. However, our minds are also able to create percepts in the absence of any sensory stimulation; these internally generated percepts are referred to as mental images. This project aims to understand the links between the human capacity for mental imagery and brain structures in a massive 100,000 participant sample. Why We use imagery in many activities in everyday life. For example, when we are going from one place to another, we can imagine our route. The experienced vividness of imagery varies greatly in the population, ranging from people incapable of producing imagery at all (1-3% of the population) to people producing such vivid imagery that it can be hard to distinguish from perception (around 5%). The project has the potential to provide important information about abnormalities associated with visual imagery and to reveal the brain basis of aphantasia (the inability to produce mental imagery). How Although there have been previous investigations into the brain areas involved in mental imagery, these have lacked a sufficient sample size. This project aims to investigate the relationship between mental imagery, related cognitive functions, and neuroarchitectural properties using one of the largest datasets of magnetic resonance imaging (MRI) data ever collected, compromised of data from around 100.000 participants. The project takes advantage of recent advances in our understanding of the micro- and macrostructural aspects of brain anatomy, neuroimaging techniques, and machine learning data analytics. SSR To imagine a brighter future for society, one must first envision it. We use mental imagery in many activities in everyday life, such as when we are going from one place to another, we can imagine our route. But we also imagine when we think of how society should be. Our project aims to enrich our understanding of the human capacity to create vivid mental imagery that fuels our motivations to create a better society.