The document discusses the concept of perseverance as it relates to individuals with fetal alcohol spectrum disorder (FASD). It states that perseverance involves both "taking hold" of a task or goal, as well as knowing when to "let go" and move on. The document notes that historically only the "taking hold" aspect of perseverance has been examined, and to fully understand it one must also consider the ability to disengage from a task. Several brain functions are listed as being involved in perseverance, including emotional/cognitive recall, analysis and assessment, self-awareness, and shifting focus. The ability to flexibly switch between tasks is also highlighted.