This workshop will focus on developing novel statistical methodology to analyze brain signals, which is crucial to understanding normal brain function and alterations associated with neurological and mental diseases. Brain signals are complex and are a reflection of the complexity of the unobserved brain processes. Thus, the primary considerations for developing statistical models are flexibility, generalizability, and incorporation of known biology. In this workshop, we will discuss the most recent challenges in this area and how the current methods need to be improved to better describe the observed brain signals.